CA2728119A1 - Method for reducing acrylamide formation in thermally processed foods - Google Patents

Abstract

A method for reducing the amount of acrylamide in thermally processed foods. This invention permits the production of foods having significantly reduced levels of acrylamide. The method relies on the manipulation of various unit operations used in the production of food products, particularly the peeling, cooking, and rejecting unit operations.
For example, the peeling unit operation can be modified to provide a more fully peeled potato slice. The cooking unit operation can be modified by cooking to higher moisture and/or at lower hot oil temperatures to minimize the high-temperature / low-moisture conditions most favorable for acrylamide formation. The rejection unit operation can be modified to reject, defects that result in high levels of acrylamide.

Description

METHOD FOR REDUCING ACRY AN141D1 FOKMA'1: K)N
[N THERMI.; L.LY PROCESSED FOODS

B ACKGR(AJNI) 0.[' THE IN VENTION
[0001 ] Cross Reference to Related Application [0102] This application is a continuation-in-part of co-pending UPS Patent Ay)pliczatioa Serial No. 1 l , 2635.239, filed on October ' 1, 2005, which is a divisional of US Patent k1?pii.k. atiou Serial No, 10/371,448, filed on February 21,`'003, atitied. "Method of Redta in4; Acrylarxaide l ormation in Thermally Processed Foods," the technical disclosure of which is hereby incorporated by, reference.

[000:3] Iec1inieal1Fi41d [0004] The -present invention. relates to a method for reducing the amount of acrylanide in thermally processed foods. This it tat n peiatait the production of to ds }.aa itt significantly reduced lc is of as ry amitlc. The me hod trelies on varying the parameters )f Various unit operations to mulipulate the tram?ur?t of. acrylainide found in the finisfited product while also maintaining product quality.

[0005] Description of Rehi-ted Art [00061 The chemical aerylamide has long; been used in its polymer form it industrial applications for water treatment, enhanced oil r covery, papermal iaag, l cculrartts, thickeners.
ore processing and pertrtane t-press abrics. Acrylamide precipitates as a white crystalline solid, is c docks. and is;laighlysnit ble i.a 4~ te.r. (2 55 g/L at3O' C). Synon ms for acr 1 as .ic e i_a clud ;
-I?aol?erat ride. ethylene earl?oxara-tid :, aery liw acid amide. vinyl aide, and propenolc acid amide. Aerylaarnide has a molecularmass of 71 A, a me't:irag point of 84.5"x:`, and. a boiling point of 125'C at 2 riunl-fig.

[00071 In very recent times, a wide variety of foods have tested positive for the presence of ac rylaamide monomer. Acrylamide has especially been found primarily in carbohydrate food SUBSTITUTE SHEET (RULE 26) products that have. been. heated or processed at high temperaturtis. Examples of foods that. have tested politv0 for ai " li#ta i.:.s#3clti l tc? C cc .. ` a1 . t d7..c;;
potato, ip h crackers, t .mh-t#i d potatoes-, breads and rolls and fried breaded nlc ats, In nexA
relatively ionv contents of, acre unit have been toniid in heated protL;irt flL ii 1o:>ds, na hile.
relatively high contents of a,:r laa ?iii' havo been found in c arh ,h4clrciie-rich f~?;31s ttcoi?an,d to nor -=dc.t .:.t` ble levels in unheated and boiled foods. Reported levels ofacrolairlide found in Various similarly processed loads include a range of 330 -- 2.300 (utg g) in potato chaps, a> range of 300 - 1 1410 (m, "k-) in french hies a range 120 - 180 t p; =k in celril chips, and le vels ranging -l.rs_?i.11 r of .letectabic, up to 1400 tai ,'1 t in varloal:s breakfast ce'real.s.

[0008] It is presently believed that cryl<a_a lid : is formed tic a a t a pres. act: of amino acids and -redu ing sa-caa s. l' ?r L,\:at iplc, it is, I . Lli.e ti. ed that a re a.cation bcm,,c ,ii fref-z a' p ar'a:.aIle- , t :. mi#.1o aiJd c.omoaP,: towld or raw S eget ib1c 9, and 'tr%-C reducing st:l 3 s tiiC's..(.'ra: l`itk Ow the mTaa'ollt\ of acir'l:innd.c to?und in fried food products. \ paaacl#le :recounts :t r <51:5Iiroxim<ik , 40";4 of the total free a aliaatr <n ids found in ran' potatoes, approximately-1 of the total. ft'e amino acids I'Muld in l-F.i4,h protcln rs>c, rzricl .11?lar<a .lalt aiz _( 14"-O (-Atl c. total free arnino acids found In wheat, [0009] The formation of acry (_am do from amino acids other than. asp aiagial>
is possible, hurt it has not yet been a;Uralia'r3ied to an6' d3. ue of cell-aim For e'a:tlm.pk% some #acrylar#lidde fornnuid01 li.ls been reported f on trr in;; ;l3.Luninr:, ircthii)Firl'1M and aspatt1. )old precursor-s. l tlcse tiudiu s are difficult to coot rtn, hmvc et; dare, to pokuti al aspaaag n :.

mipui atl::.s .in stock amino acids, i\oactllelezss, ,a, pal a`nnk. has 'e i1 identffi~ d as t -3.c arilaix'. ca(:id precursor most responsible for the formation of aei l tmide, p0O10; "itls.t .it;.i''sa101it eJ in fi)(d- iti 1 1t.t:en-tlv discovered pho-zlomLnor, its t t16:.
n-iecllnuis_1-il of, formation has not been confirlll.:d. however, it is rrow believed that the rno t Iikely route for iacrylaim.1de Iorma:tion involves, a':Fktillard reaction, The I -lai1Iard reaction ha-long been recognized in food chemistry as one of the most important chemical reactions in ood processing and à in d.ft"ce. t a or cotosr, and the nutritional alai(: o tb:, lofud.. The \laillarI
reatttionl. requires lie l.r. -i.yioist'i1 e, red1 L,111 sug lrs, and i -nitro acider.

[0011] The Maai[lard reaction Involves a series of complex reactic ns with numer rus intermediates, but cap. be ; Ln Ãelll\ described s involving. three sets. I
Iic ii'st step of the Mal.llal'd reaction involve", the Lomb11 anon. of a 1're ,iniino group (1roni f e i rhino acids and. /or prof im) with 11 i'cdo .En str~ aar' such as glucose} ft's form A-niaclor or I
k 1:1 rearrangement.
products. `I he second step .in -olves degradation of the AT- aador'1 or l ieyns rearrangement products via diff rent alternative routes involving., deoxyosones fission, or Strecker degradation.
. c ui11plex scr'ic=s of reactions irwluding dehydration, elimination, and ti'a ;incnt itioil result in <r pool of flavor ill t,:1 nu di[:1to and flavor . onipoun ds. T ho third step of the \l.Lrllarzl reaction is ii ir%ictki i od h1` th, fonna.l_i ?n of brown poly-3-nor-'s and co-t i~1;:1 tltL \1aill<ard rear on a tilt li :.I rr}tl[L lilt' lt~
Ii~rtll:ttit~I . ~t <it.a;:lairlli: l 1 ~4.iit polymers, I illustlat a simplification of st1_f~,c.till t tliwa s for the formation of acrF 1a. i c sun' in with aspta agile and gliuL os:.

1001 ' J Acry lftmriic e has not been determined to be d ri m ental to, hu mllans but its presence in food products. especially' at elevated letels, is undestrable. -\s noted previously, relatively 11W.iler concentrations of a rylamidee are f6und in food products that have been llcate.d or thermally processed.. The reduction of tcryl r iide in such food products could be accomplished by reducing er cllnana :iitg the precursor compounds that lift.in aciyIan.iidl , iithib:iting the formation of acr'vlami d< during the processing of he food. breaking down or i eeacting the acylarnide monomer once lbrtarecl in the food, or removing acrylwalide from the product prior to consumption.. l:%iid.ersta ndably, each food product presents ,ii icli.ie cha leng to accomphihltn airy of tlte: above options. Fo ,x in'iple, foods that are sliced and cooked was coher .tit 13 eves iria not be readily mixed with various additives ~vithout physically destroying the cell str uctu es. that give the food prodiic:t' their unique chara. teristic.s upon cooking, Other proccs,itug, Lquue c tS
fe,r _r cit-:ic fbc d products may like: seise rrt=;tk ;.t r lailiit_1c reduction stt rategics incompatible or extremely difficult.

IÃit 13] By "Skit t c x itriPl ., 1`it,a#i iliii tlatci i4'i=ll. ii fwti prior :al't Titetll t4 .toi ril.ti.iii :
fried, potato chips from, raw potato stock. The raw potatoes,. 1 hich contain about SO% or more water by vei ht.. lir.st pwceedtti a f 'cahm. cep :v1, After the .k us are peeled from the itt v potatoes, the potatoes are that, transported to a sl.ictne, t. p 22. I 'he thii.lklac:ti , of each potato slit e ,it The slicin- step 22) is dc=pendc.nt on the d si.rtcf flit. it ick ac s ;
of the _tin d. product. An example in the pi.,no :ir't involves Slicing the potatoes to .i: tliiclSntss of about 0,04 to about 0.08 inches.

These slices are 1 hen transported t[.l :a FFashin st<:p ., wherein tlhe surface ; tarch on each slice is removed with 'water. l'lie washed Potato Slices are then transported to a cooking step 2:4f. This coolkrn; st .l 24 typically iÃivo1F es .trt iag the slices Iii a eontiuuous 17ry er at, for c;xani plc:, ..tl ou't 171 to, about 18-')'C r 31f1 _ ottlT3 for 'Ippr'oa<iniatel t?Nvo to thaee.inuuite: , I lie= cooking sicp generally reduces The rti.ontwe level. of flit` chip to laws than : % by, weight, For example, a typical fined potato clap exits the rst#= ssitfi oaf?pro.aiin;.tith I -21 mo stutc icy, wei fat, he cooked potato chips are the ii trans-ported to a se asorun step '25, where sc.a crrungs are appli d in a .rot.ati.on diutii, l "halls-, the seasoned chips proceed to at elt,agin~
step 2 ;. Iii s patc.ka nng step 26 usually lot. olF'es feeding the sf- .asoi eel clips to one or more weighers winch 111-ien direct chips to one of more vertical form, fill, and seal machine-,, for packaging .
a fie: iblk package.
Once pa<,l tiered, the prodiiet goes into distribution and. is purchased by a consumer.

[0014] Minor adjustments in a number of the potato chip processing steps described above c: an result I sihnific.: int changes in tlac Lh aanz.tst . (if the final p F' W ct' 1 ii exa-f-a l.c, an ex idod residence time of the slices in water at the 1:= as+ti.t3;?, stop ,2) can re:wlt a'{l leacraixat=

compounds from tl-, slices that provide the end product with its potato flavor, color and text ire.
]mere aced residence times or heating teiripe3attlres at the i ookim, - ep '24 can result in an increase in the Millard l r'owni.i levels is the c.h:ip, as well as a lower ainoisture content. If it is desirable its tF3Go3'l?i?.i'aw in!- rcdients. into the potato slice Prior" to ffi tio, it may be n `ccs. ai to estat.,,11s1->

wcchamsrl s that provide for die absorption of The added ing.,yedicfis into the interior porfion,6 of the slices N ithout eiisri.i tin the cellular structure of the chip o leaching beneficial cornpounds Iron'.. the slice.

[001 4; _1 B way of another .:\tiriiple of -h:e.alcd food prodticls that represent unique challeia ;cs to reducing, ai.r\lamide levels iil tilt! final products', snacks, can also be ni,ado as i I.GFI?i-#s<i31i:d snack. The term 'fca'iiit:;_atc : snack"' iYl'`.ai1S a sniicx.
~ food that ti?+:s as its starSl.t,;
itl r`.Iicilt vsarlaethiiig other thane the of-Igin l and uitait :rt d stau .h\ st rtirtg F laterial, For .maniple, fabt'icatad ~tlac .s iUclUJet<tbr cat d potato chips that tisc.. a dehydrit.:r1 potato product as a staning material and corn chips which use a masa flour a its sta in .t7l t~ i'ial. It is noted heae, that t:ho tleh\ Jrtited potato product can be potato, flour, potato flakes, .l sit tti? granules, (.,,r any other lore in which delivkhtat :d pot:awc. exist, When. Frl of tics. win's mro Used in this tli,l:ic.atic,ii it is iaii.lc rst ood that all of these variations are.
iil.i.li.i 0016 l ef~ ring back to Figure 2, a fah cited potato chip does not. require the feeling step 21, t c. slicing stop 22, or the w -ashing step 23. Instead fl blri :.aced potato chips start ww-ltll a deh ydr,atecl potato productsuch as potato flakes. 'The dch\- d ata:d potato product i nst-.cd t( water and other minor e:rigredi nits to ors' i a dough. This dough is then sheeted and cut be-fw Procoot it to a is 6kinng Step, " lle cooking step tr <.w i- o1ve :Itsintg à r baJ iiig, The chips then proceed to a, so 1S.?I1iiig stiff w id t pacts xg tl ' seen The mixing of ti et: potcat) dough geti r'a1.l ' lets it,et% ti? fl-,,w easy addition of other itig cdients. Conversely, the.
adJit:iori o such in ! of ielits to a raw food rroduct, such as potato slices, requires that a mechanism be found to allow for the pcn ti ti ?n cat irr led .nt~ _nft the. isc~lluLu :sÃrrr trim. ~~l thc~. pr ?
srr~:t. ll~.rv . r, Ã t. t3~.li: tirfr, f~Ã' i fi;
it s r cdicirt iii tdr< irri iri step must be dwie ' itt:i the e,O
NNrcderatic?ri that the _irr&redienV: rimes 4idverse.l\ 2rlteet the she :tMg di t 1a :t iistie of the dough is well as the ffii`al chip charactL:r\fics.

)()1.+.I 'it -,,vbe. desirahh to Ã. clop one, or more methods of redricirr thi Ic cl o ac,r tIm ide in the en 1. prodri.ctot heated or 1h errrialzyl ri , c w.l foods. ldeall~-, sucli :?i'ocess should substantially re.duce or eliminate the eeryl rrititie in the end product itd d?r.t#. e.i~.dce rely affecting the qualit : Ord characteristics of the end prouct. 1: urtdrer., the method should be easy to implement arid. preferably, add little or no cost to the owrall process.

St MMAR: ` tll; l'`I'll'. iN 1 N"1 11_}`

[0018] The present in ention is a method for reducing the amount of a .ryl mide in tl errnal lw processed food products. According, to oll embodiment. the :i .zethod comprises providing a continOotls teed of peeled and sliced raw potatoes wherein he continuous feed of rya .o pot _ato \li c.F> ha v- ; at least SM10 of the potato p . r .mo od, and lrvila the peeled Potato slices, IITl a3 Single unit operation. tO ,$ raae)1ht.a 1't COr1$eaaà of hL1\',, n :about 1 A% to about. 2 by YhÃ, `l "he it d potato slices can then l:ae analyzed Jot` characteristics known le, be consistu-It with potato defects and those dried potato slit era having such characteristics are :r'a:.move from the food product stream prior to packaging.

[0019] The above, as well as additional t'eab.ires and advantages of the is 1ati as will become apparent in the following written detail d description.

BRIEF DESCRIPTION OF 4'D IE D AW INGS

400201 The novel r.aa_nes believed c h rmAc istic of the invention are set forth in the appended i. ;lor s `flee, invention itself. bo ...e e;r, a is =ll as, ar pie fe-ffed moth of use, further objectives and adl4 rntage tire;-eo1. W11 be beq understood h reku.u. to the.
Moving cktAlcd.
description of iiInstrati ve: embodiments when redid :Fri i::onjunc ion with the accompanying drawings, w herein:
[0021] Figure l i = a schematic of suspected chemical paflrmays for Far.r-yl imid ftorlrtation:
0t'0,' 21 l iairre 2 is a schematic of prior art potato chip processing steps [0023] 1' igure 3 is a graph showing, on the y-axis in parts per billion i b ), acrylamide conceintrations of potato test samples that were ried after contacting it various ways described aloe tl7e X-axis, as aell as the final moe flirt conterit by weight;

[0024. figure 4 is a graph comparing the original results from Figure 3 with the I igure 3 results after normalization to a moisture conterit of 1.32% I A." ,eight, [0025] Figure 5 is a, graph showing the r latio ns.l-lip be ~,ween.
icryIamide :oncen-tr<rtion and final fried product moist r're wherein the acrylamide concentration in ppb is on the v-axis, and the moisture content in eigfrt. percent is on the x-axis, 1.00' 1'`igure 6 is a trapti shiiw i.og the ; .ati nship lxtnttn ii,:i'k'lan u(k .ni..:'rrt ation and final baked product moisture wherein the wacr'I rru2 concentration in ppl) is on ilk y-axis, and the mo.istur content in Ak''cig.ht percent is on the x--axis,;

:xrir+,. a3 is 43 .,, l t ~L , t".}iirntrzitr s 1 ' a-t"T test aSamples ~8t,2 ,. %~ ~i graph 4}~'F~"irr~ i t.~e. ~:t~iRl ,:rl'.11ra<.rrS i ,;ri l isthat were pa fried and. -then oven-dried at about RON (2501", ) after vZous, methods of conlt cti_ng, wherein acry lamid+e concentrations are ~ ]{-:=! ? on the y ati is in pph5 and the c'arious contact methods are described on the x-axis, [0028] Figure 7b is a graph showing the last six data. points of Fib uri 7a on a narrower 3crylzamide zonceiatr.a[iotl scale;

[0029] F'ieur : 8 is a ? ".tph showing the data from Figure 7a after nerrin.<7lizing the pox-fy data to a moisture level of 3,:13E%e% by., weight and normalizing the, oven -du data to a i no_istur level. of 12 5'%by w :iglat 9000E Figure 9 is ca graph showing on the, 4 axis in pph: 1) the acrylamide levels of Potato teet s atalpIcs that were contacted in th. , various n. ay-s shown on the x-axis,,, thE`p p.ii 1-iiei at about 178 C Ã 35 f I ), and 2 th acTylami de levels of those-seam potato test sax pies after oven drying at about 176'(,, (350 l;'), normalized to a moisture level of 0.76E' i%
by ~ c a lit (00311 f igus: 10 is a char showing the operating conditions and results of an experiment in which a control sample of potato slices was ,-atmospheric fried to 1;4%
moisture by L-veighht, and a test saml le \v-as tatiliowpheri tried to 2 S c> ino `<tun by n . bt, then Overi-dri d. to 1, ss~, moisture by wei.gjat;

J(032 F mute I I o a clia t sho,.i`ing the opcranine conditions ai.)d -results or est.. end experiments in which a Control sample of pow-to Slices, ` a atmospheric fried to about 0.8%
moisture by w ighat, and four test tiainples were atmospheric. p r-- r#.ed to about 3--1 {}% moisture bY v'eight, then low-tofaai pematuie vacuum fried to below 1 moisture by weigh ;

[0033] Figure 12 is sa chart ' hos ing thL operating conditions and I suits of sevela experiments in s '11F~1"t -loth test samples vv'er< a r-iospheric tried in oil 4t itI1 initial t mmper 'tures ranging bunt about 165 to about 180'(' (329-356'1-,') ho about 3-4 i]iliafat '~, and tl ic.e tt-t samples were [? 4' t = 71 ?~ f'~t 1:EÃ' v'aeuu.Ãn tried for about 4-10 minutes at temperatures ranging foal about 100 to about 140'G (212-284'F) and à .,ssur s iaÃ:u in tram 5U_100 millibar.", and [00141 Figure 1 .a is ra. chart showing the level o dcr1lamid.L versus mo1;itUrc 0E?A?lilt for potato chips t jade from potatoes having -three different levels ,s eel. rime ed and fried at ambient pressure. and [00 5) Figure 13b is a graphical à :I?Ãese t~ti sÃl and trend line of the data presented in Figure 13A a, IDE"I'AILE.E3 A F.'; 1.~\ a.1=.F 3.!V l 11 EFI.3-.. INVl_'NT1 [0036] The formation of acryla mile in thermally I~rocessed fo ds .Ã
i:~litires a1 stark of it is l~ fsi }ft~~ i r . l that carbon I ; provided b a :~ai'~~cil "li a <e, source and iiitm-en is provided by a protein source 0rlrtxi_0u ticid source, I
iti plant-dc n cd food iiat`.iLdients such as .rice, 'heat, 4om uvle'4', soy, potato and oats t ~iiA ,In t3.3 a <i4?.lne and are primarily carbohydrates having minor amino acid co t pone ts. Ty ? 4 lly, such food ingredients have a small amino acid pool., which contains other amino acid,, in addition to asplia: tne.

[00371 By "tl?er.'tiially processed" is me ant food or food. ingredients wherein components 80T, of ffie food, ;such as ; inixaire of food iuci'i.'ilients, are heated at luOperati.1res o it least 10 P. e.f rahly, the thermal processing of the f?od or food ingrcdienits takes place at between about 100`(. and abouà 20.`5`i C The bod i ie`iedient niay be separately process d at t.la va.tsd teiript:rta.tur pins to the f:uri_iaaÃlon of h :. Iinal -t>cxl product . An e\a.ia`mp e of a the malt processed loud ingredient i5 potato il<ales'"VII-Ich is t'o.u-ned from. r i'S3,' potatoes in a.process that exposes t I:e potato to t.Giiip t~i itiiic.s as li.uth at 170'C. l ?i miples of o1h r thermally processed food ingredients include processed that par -boiled and dried rice, cooked soy products,, corn inisa, inlasR c coffee beans and roasted cacao beans. :\ltern itis.el ', raw food uwgcdlents can, be used in the preparation of the final tbod product, wher iit the production of the f aal lood product includes a thermal heating step. à ne ex it iple of raw material procc sai g -S3li..iem the final f >od product esialt5 lfoi11 #. fkerinal beaiin ; sÃel? is tl:i : [ai aIe+3l'caz'f.t#I of potato chips lieoi i.aw ' l,iitat slices b tin step of frying at a tempertatui'c of ftoi`ia about I00T to about 2OO'C or .h production of french fries fried at similar' temperatures.

[00"381 in accoidaiic> with the l``.LCS :nt ii ` utit ta lio\ e\ ca', a tia#_miflc a;it to5rinaÃit n of i i siaiFiitle has be n toui d to occur vhen -ie n..a.ux a id a.~PI<'ii'c#
i31< Ã . liC` Ã'f.tC in the pc o- `Ãa $IY"i of a reduciid_;' suga:r, Floating other amino acids such as lysine w id alatli.ne in the presence of a t .il aic ing sugar such as glucose does not le d to the f rination. of a ;ry laa r de. But, surprisingly, the addition of other amino acids to the aspa .tagin sutra mixture can increase or decrease the airrunint of acry! amide ormed.

[0039] Having established the rapid formation of acrylamide when asparagine is heated in t1 .= presence of a reducing sugar., a reduction of icr )amide in thermally processed f ods can be achieved by inactivating tll. asparagii1: B "macti ati u_" is meant removing asparagine l.i'+?lt the food or rendering aspaeaM.iit[ .ilC?.i'i-rcactl w ar along the ace lamicft tE?.lI 1ation route b means Of, coil w er ,ion or binding to _another chemical that interferes with the fo malion of 1 ~cr "la.mii~ e i`rt?m as ara_tgIri ~

[00401 In t stigationsi into the of cts of, the various unit operations or processing step on the formation of'aCrylamide .in finished bod products have lead to interesting te"sults. I ie. t i :sia.lts G.fi i:i3e?ii traTe 3tl i:3?ilit4" lil i>lcilitt C`Jle. i t T1C)i'L' unit fal)e-i' ti;)ii5 iit 3i1 ' I

pti_x cs,s h -)r inakiiiõ a food product .o that the resultin,.' cooked loud piodtiet has t rcduccd concentration of acrylatnide. By. `Yeduc ed.. c one entratIein of acry iail-lide is illy t11i_ i co ncentr'ation Of act lan7tide that is to w'er than the concentration that would have .formed during an unmodified prior art process for cooking. t e particular food product in question. .l he terms "reduce colwelati'ation of ad s`larnide, induced a .ci .l;itilid (=?I ~i"3tl;k'ttt~il_ and "reduced acr~.-Iamido level" are all ti c:() int rcli ink eabl Ti this TI J.I Itlo.n. For the pii.r 3f st of this application, "unit operations ire iils ai i fiiliil`l:: sL mcnt of an Owt'iill method le t' prodti ing i foo prodliet.

e'xatÃt pee' i~ re-f 'ing to F~.i=gu each one. Of the potato chip l}iocessia k steps itf~ pee li.i s step `' 1 the S11611- step 22, the -washing step .Y?, the = cooking step 4, the s,_,i'.unirniw step 25, and the packaging step 26) is i:ausidei'L=d a separate unit operation with regard to the o vc' r pit?ces o producing a potato chip food product.

[0041: -A first example of the ti anipul ati n ofa unit operation involves the %Nashing st.e 23 (illustrated in .Figure 2) of potato chips produced bye slicing raw potato stock., The prior art method of washing) slices involves rinsing th chips with water at room temperature. 1lhe iwerage residence tim ; of each chip in this water rinse. in the prior art i s typically less t hall about 60 seconds depending; on the equipment used.

[00 42] Figure 3 illustrates how tb,: chip washing unit operation can be 1'I7i3:[3ipul-;ta L ,kf a that :it.rYlatniL.lt: IcvC S In the. finished chip piOL iutt can bt. ad,lusliA
Ac-cording to the present i.n `t,utimi, the washing step ,2 con be iii lail;ited to comprise A .ont ding step, where a continuous feed of potato slices is contacted with l r ii;_ic us solution for residence times and at temperatures that Jitter f oiath se used i.n. the poor art wt3s.l-3.uu step.
Figure #. a 'hart:

ditty lnc on the left (trot the v iewvc:t , per'spect v ) vertical. or x\-is, the amount opt acry:la id. o (",,kA") in parts, per bill oti t , +.,) found . Ãi th fi n.t=.lii. d potato c ls.i p lyiocit et. The rigitt: t u n.:tl_ or 4'-= taxis of the mallin Figure 3 shoots the percent- inoiatl.ire by LY
fight in the timslita chip product. ':flit, at :r I ri i.ide level is c>.h.,mted iii thegmph k the eiti al bars, whkile the percent moisture level i.s charted by the .line plot. The horizontal or x axis o.( tli:e. chart sho"vn In Figure 5 lists t'ta:rioas proctS.sI c par =tinLter changes r adc to the washings, unit operations, of a potato chip in iiuuf,uc.turi'ti Process, TI-I. cooking tint; arid ter periturt Nvc'c identical for all product I, .Es ,. ¾Ic tacl i.ri i tare..?. Specifically, ,an.b sample S i x tried it about 178'C (3`531'F) 'ho about 120-140 seconds. (: fir cgtientlt . tie moisture levels of the end p >>dta:t terlded to vary.

(00431 B way of comparison to the rt.: ults sho 'n in I itrare .f the prior art sv.ashino tit;;
described above., using chi stock potatoes sliced to a thickness of .05 iinches and flied at about 1 7:'t. Ã35: "1 ? ter about 12()-140 seconds, results, in a finished product havin an ac.ry am +de level of about 100.500 pl?1? ( s'-hich .c aii be high r depending on glucose content and othor pot tt:o stoc airlrfl le ) and a final moisture level by weight about 1,4% This 1 iot' art result is quite Siitlthu to the fast data point 31 tour on the chart ho'~1:n .its i i.guire -", which more:' cnl the base data. point and involves a washing step with a water residence time for the potato slices of two to three miritltes. M;.iiiita:inina all other pa.ramrieters in the o- rall processing of the potato chip, this mil or i Mange in the washing Im.11 operations re ults iii no noticeable range in fl -w 3crylamid :

level ; ai;?l .r~?aiirr.ttn l~ _?;~t pph i or the moisture of tl-w finished product (approxii?.mately 1 ,: 5%), as compared to a product finished according to the prior art Washing step, ['0044 The tut data point .12 shown on. [Ilk graph in Figure _s reflects za change in the , ill iai, step that coniprises contact n the potato ,h... with ss at rail the ii<liic+3irF; ,olii#.ic?ti.
increasing the contact tiimi sfthe aqueous solution with the potato slices to ten. #:ri3.rii.ites, and increasing the temperature oft e. aqueous solution from ambient or room tG3iiper atiai'e to about M"f:. Ã1 title Pp. *'['his adlii.isti t =i?t resulted in a} docrea : of tlh.e.
K 1 v lair ic.k ill the finis(ied p.ioditet to approximately =I' 0 pli : .acid a reiluu ti on ill Ãlie n=iol turc level of the imish d product to l :s`i than ~~' `g n it ' tl oiiit _} y reflects thait. it cr asi3 g the `ia meets so utltan (a ain, water) tetitperatu c, to about : 1='C t l 30,) with an average contact time ol'five minutes did not result in zll~l~i t:G`iabL ' reduction in a ,:i G la;mide levels in the finished product. By contrast,, the fourth data point 34 demonstrates an appreciable reduction in air r :n _lc. levels in the final product (below 100 plib) ;-lien Ã13 . wash.ing unit operation invoh e a contacting step prod iding one minute contact n:1110 with an aqueous solution comp.Znsmg water at a temperature of about 'M"tY i l tl`l i. lit?tx ve , the moisture level of tile, end-product chip was nearly The lfthh data point 35 reflects that is:in`, a 1% l CystCinc solution as the aqueous solution, at ambient temperatures for fifteen rrair utes.. reduceasthe acrylar.rid level in the final product to less than 250 ppb.

[00451 In the graph illustrated. in Figure $- the experiment results shown in figure :3 (the first of t:ach pain' of v Lrtit,.tl bars a t : nouriali ,.:ti to de:pic;t the a. rv t:tt:t iids level., that could be.

expected if the test t:aaria;l le:s ,",e:rc tr it'd to the sai.i stare laa.tdrie:d moisture level. ttla . second of each pan of 'S a.:rt:il al bars), is s unarms that the p~ae nt Elena e in acryJayrdde level is inversely proportional to the percent change it tlae.moisture level when zamoisture levels are low, the results of test data sbuc va in Figure 3 s.=m be nortiat_rliz d by intiltiply WCibL.
aacta it ~rcryla m. e levels by tlie. titittft change Ãta the i'ioisti.trr It. :v e:l s required to reach the final ui.ols-turc level of the base. standaad sarriplc. Normablrta the c\T?t:ririi;Cilt data to the sarnw=
ivol tote l :'tel allow one to more accurately compare t}a relative effectiveness of each contacting method at reducing aacryl amide. tol-talation.

[0046] deterring back to Figure 4, the vertical cxa axis is g aain labeled in ppb of acr'vlata id . fbtanÃt in the -finished product. ' he horizontsa_l or - xaxis is labeled to show the pit aaneti: is ot't.ach data point. In l f uzee 4, c,at.h data poirst shorts a pair of seitit,aii baus, the bats on tla, l l't ofa air are inipo te.d from Figure ,:hilt the a on the right to a pair reflect the expected results o the s an e contacting process l aa aairie el a iftthe find product t%-ere fried to a unifoi'ta-a or standard tzed moisture level of 1.

004 Ont..: again, the first data point 41 is the base sample ins oh g a two to three minutes'arcs'wash at ambit.uttemporaitatro. The 4; c..cour d ta.poin 4'ilivolsm.sthe coataeIIU_`
step act.ot' dine to the present ins .saris o where the potato slices are cwit.at.'tt is i h an agtit:or`rs solution comprising 4'ater at a temperature of about 38'C (1001") for a ten minute contact tl.rne, The left-hand bar again reflects that such contacting folio we dd bs tus me at al.Irto tn'tels= 178 ` t.:`

? _ r t ~. ..
(..,,..-3 1") . fi}i'ct~x113 1.~~t-1:~ sA'ct?IIC~i.. will result i.i1:J11ti e~~'a:i ~:,~3~3 ppb aGiyhi.33.i& in the f:imShe:d product and a fi.riished product having a moisture led of less than xb.
However. the rght-khan bard .ni n sttates at if a chip thus contacted were fried to a standardized moisture level of l,'$2_%_ the pro: ,_d acrylarin:ide level would drop to apprc?xiztmatel,- 150 ppl,.

[0048] A sirixiÃIa desirable result occurs with regard to the third data poiint 43, while the t<,itrtli data point 44 r fleets that the reduction of The Tnoisture level of the finished product sii.;~ .111v raises the cr bride level t'owid. Biter iii F the last data point 45 reflects, significant acr y1aw. de .reduction when an aqueous solution c {wp`ising 1 j~'"+1 1 -Cystei.n e and fi Y
contact time is'useei, i3rt i<:rrfk{x3 a:, a particuJriy low acqlam.de leL'41 is t?,~)leeted for a tThai chip moisture level of I , ' %) by weight, Ti .is ako inter :sting to note that the prt,ject icrL''1amicle level for potato slices ct ntac. :=d with 1{'{ l.-C t steine for a :fifteen-minute contact 611 2 is nearly the same as the, proà acted ie:v'c:l for slices contacted an aqueous solution comprising ww' itei' for ton minutes at about WC (100T), [00491 .Acoordtnlg to other irkbodiment =, cout.actin the potato? sl.acc:=s with an aqueous, Solution tli th er Comprises reinoL 1ng one or more ai iyl+_u ide 1?recursoa s, such as a`paragine o:
ri c tiff iris oily trti .ti`iFm the raw potato slices by 1 ~( 3~ ing ti..i4 h ;:fie t 4'1 i31f{lw'. precursors oul off. thy, raw potato slices with a potr_i-to extract or a leaching strum. Leaching of c inpcneiits III, the potato slices by the potato extract or the .etac hin4-', ti{. ti: `l occurs.
Ibr those components for which a co centratioi ?#`adi .i{ exist-,, between the potato shce. ,. and the potato extract or the searching strea . The leaching may be accomplished selcctlviA by a potato extract solution that is deficient in the aerviamide precursor to be removed, but has cc ncentiation levels 01.oth-cr soluble matter that are at or near equilibrium St it:l.E the corresponding COQ;i,:i:<ntratiorn levels in t l.e potato slices The leaching may al.ko he accomplished t.ou selectÃively by a leaching stream sudi a,,,,. pure x wa,te:-r. An example of selective leaching :Involves ma-king the potato extract deficient III
aspa.ragine. and t en contacting the raw potato sire va with the apt"?rag'.ne-`iefclent. Potato extract to loacIt Lisp artiig11'ic out of the raw potato ?<.eit P iC i...i rding to cm c n k dime-nt., the potato extract deficient in one or more 'i.cr l in.ak precursors Lontac ti .e i potato dices in a counter-Current fashion, which may lead to more effective leaching ha a parallel 'low.
In an.?theT
embodEment, the leaching is further enhanced by ultrasonically wib.rating the potato extract whi e it is in contact w, th the potato slices. If desired, the potato extract or the leaching stream can be treated to remove the leached Taerylamide pr"ecura rs so that the potato extract or the leacchil g stream can be recycled for continuous use in t cl le.achir g ot`mor=c potato slices.

[00500 One point that must bi: kept in mind when i `.tut in; file effects of rnamlpulatirigl various parameters of unit operations, such as those effects shown in Figures .s and 4, is that al of these adjustments will have some collateral e-ffect on, the qualit. and characteristic of the final product. Con.secluently.. any ar justtrrents made iln. a n of the unit operations must be ca- re-11illy sclk.ctcrl in order to arrive at the product exhibiting th:
desired :final characteristics'.
1 h ie clrar4le..'r"1 lli ti rr c.laait : color, flavor, mouth-feel, density, # cell. and the ~hc t draw aspects of the finished. product.

[0051 ] Figure 5 focuses on another aspect of unit operations and show;-, the effect of clecleasin nrroivturc: level in the chip during the cookie stae:c. Referring back to Figure w. the cooking stop 424 is a unit esperation that typie.allyi vo.ives cooking sliced potato chips in a continuous oil f ryer at high terrap :lr.attrres. Returning to Figure the graph thereon reflects on the horizontal or x-axis the moisture level of the final chip produict. The vertical of V- axi" is, again labeled in ;pp1 o aci'lkimide ("AA".) found ni the final product. ..
Frtmbci of data poir_tt;.;
are then plotted showing a percent moisture versus the. acry i ani14de level of the final chap.. 1 wo different frying t mperatur \ : used with diamond symbols representing chips fried at about 178 C (531") while square syeaahols are used tiorepresent data points for chips fried at about 149 C (cif(; T). The line plots 51, 52 are curve-fitted to the data points i.n order to establish a trend. The curve-fitte line plots 51, 52 follow the general equation t = c. x h where "y"

represents the acrylamide level, e ' is a coà stant,, "x" is the .à .Aoisture=
level, and "b" is the c l c?rierit of x..," The first line plot 51 relates to the 149 C (300`F), frying temperature data points. The second line .52 relates to the dat.ai, points plotted for the 11.75 C (3531) wryin tk.iCil~G`r't3t#irt. As can he seen in guru. x, acry'laimide. levels remain ver;F' low at chip mi r i i levels above about moisture by ,vcight regardless of frying temperature.

[0052] Whereas Figure 5 slic{wa,R the re laatit n rltil cr l midi levels and moisture content in fried potato slices. Figure 6 depicts the samie relationship in baked potato Chip products made from a (Irv prix. `Fhe vertical axis of the graph in Figure 6 sli.rw erylaa:amide.
concentrations, while` tlst ho zontal axis Shows moistuie level's by weight.
While the erwlar:t3.ide concentrations tend to be higher in baked potato chip products than in .fried potato slices; 1' Ãgure.;

1J 5 and 6leot h show that the t7.ci'y atnr;i e. concentrations remain fairly low in cooking potato products until the moisture level falls bell w about 3"ii.

[00531 What is made apparent by Figures w and 6 r: that aerylamide levels rn potato chips 3r~ .;
cooked in a typical fryer in rease rather dra1natÃtall\, once the moisture level halls below ..=%
moisture 1-y \=veight, at. which point it seems ther'e is not enough moisture leti to keep the product temperature below am acrvlainide. formation t .rriperature. For is liati ?l~
Figure 5 illustrates that the bevel of aacr i lamide: found in the :final product is relatively low when the moisture Jc el of i._.he -r U' v chip during the cooking unit operation is 1e~ by, weight or greater, regardless of t fie exposure to high temperature cooking env'ironti"teents. 11"jan es 5 and 6 demonstrate that moisture level is a Useful additional par meter in a unit operation that can be adjusted -?i 0-.-w -reduction of nrylamide ki?I=mation in the final product, i0054I l_inlbrtunately the moisture level in a finished potato chip should :iiieally he below about 211 , and preferably between about L and 1 Arid hiilg hÃ-her than 2%%:tr, and ever hip her t :ian 1.4l '4,'% cu lead to staling and ilii~ ler'i al spoilage issues in the packaged product, as w dl as or .'. a.ilokeptie. collset-11Ienc ,., for L.v mipit_, taste, ti~xturo.'.' etc. However, changes, in Color, taste, and consist. 1lL 4' of tl'i.:.tif I product ;S.ii`i be i(. ju tt.d. by \ai 10Us rne.,ins. In addition, it may be possible to counter the consequences o:f finishing the food product with ,a higher moisture 'orltem by ad1u tim. 'a'rnous tactor in the pi e -pa:.ka.õ#ia step, such as extendl.n : fryer llt:iods, cu : ei i.il u conk'e ;oiti to the packaging mddn n. , IL : hum idit:icat on of the plant environment, and iLUIOUs taciors r"ir. the pa k.1 -i.[lg, such as at. kc pin iil i. il:il .
films, Naps and scais, I bus:., according to another embodiment oft e disclosed method for reducing mvlami e formation ii).
tl`if;'nn)afly processed food" , a :further- malt opctation comprises.
finisn.tiig the 1ooi f1od :I Ã as it t:ille-rges lion. lts final cooking step at a moisture content fo :Zam le at about b-y weight, about 1,6% b\ weight, d bol.a.. 1,8% i weight wid aboi-if by weighl, or at any moisture 'eight between .t 1 a and f0.

[0055 1 However, it is important to note that other potato products' have been .known to form significant ainounts of :tt;it 11 iii(Ãde a'-.Len ,.it relative( high moislun. content. For cvamp1 .., french fries, which ti pica.(( leave a fryer with over 151,`4, moisture by'.
n..>igbt, ha c boon shen n to develop i Y l1-.cant airiout:tt; of ac.:.t\':ami .lL during Cooking, This IlUg`tc' {s that. rxcryli nut e torr[la3ti ri depends on t.l.C temperatui'w. (particulai'1t the sw JCL.. ei-ripetati.2re) of ai cooking product rather than overall moisture content. In (-.act, studies, have shown that ac=.rylar7l0e= does not form In significant amounts until the n e s li 4'' :r6 t<ta13t. arc exposed to à -imperatutles of about 501f 1 `0`'C It thus appears that a potato product containing acrylarnide precursor coF:ipound:s will.
not f orm significant amounts of aerylamide until, upon cookin g, the product Gempe'amre. which may dÃtt {~ i ~"t~~~. 'T - .: r a~~,~~Al~~.z~~~tl~~ from the cooking rt~E:E
se;~iper~ttatre, rises ~.~ ~~~c~~>~. ~t~~t~t.t 1210'C

(2;50 1 ?. e i l d l ~s, the moisture content of such product can he a good indication (A whether the product temperature has risen above a,fd?rr-aton t.einpe_r t iire for a,.ryl&tnide.

0056] It has been theorized by those of ordi #:- t'y skill in the art li.atmoistt:rre in the product h =lps keep the internal product tell pe.iatu e below the acrylam#de formation leyri.pei ature, even while in a rel<ativel` his=ti-lc:Flil?d'r i#t.ii`d" errvire:?iiiirti`r t., When most of the moist ure is reinoved, o e :#`, gs can cause the product feniperatiJr , to rise abov'e the-1 acr4'1:3I3'iid lE>.t'.t32 itio to p r itili It is import u t to keep in mind, hough, that not all portions of a cooking- product share the same internal temperature. French fri s, for example, can be fairly "hick When toms pared to potato slices and thus tend to ha a larger moist ire gradient between the inner and outer portions of the product. Consequently:; it is possible for a french fry being cooked to have a fairly high stiri'hce temperature even though. its interior i roisture content is high. In contrast, a potato slice is thirmer and tends to have more consistent moisture levels tlri t?iz lout the slice during cooking. Thus, at least for thin -products such as Potato slices or f i.bric,ated potato pieces. moisture level can still be a good gauge of its, iiit _rriaal temperature. This also holds true <lr ric n-potato products made from corn, barley, wheat. rye, rice, oats, millet, and other starch based grains. Furthermore. continuous cooking equipment can be de i Veil different temperature stages that. progressively d cre._3se from higher to luwe temperatures as the moisture content of the. cooling product dec.Feases. This einaable, moisture.
to be removed rapidly Without ia.ll:owE=ing, the product temperature to rise above the ;.i r F
1F3i]iide ttii'rli ition temperature.

[OQ51] C.onsecfuentl0' one element of this invention involves dividing the cooking unit operation he -berth unit operation 24 shown In ]Figure 2) into at leatit two separate heating steps A first beating step occurs at elevated ten" temperatures to reduce the moistuie level to some point near but above 3`.'"(r h nnLighÃ. The product is thL=1 finished to the desired moisture, level of about I by weight, but + ~ 2p 7icl Zrr ibly about bà 1.4% v Q k.: L % ~ ~ t~
~i'v'C<Il"~ ~at , ,. '~if.,l '.a l<~5 +.'A^tLEli <'1'i_t'~t.1T4.`. cooking step having a temperature below about 120"L ;25t f 1F'}. 1:10w-ever. the pro ess rmaoditic,. ions described herein are not limited to prior art processes for cooking potato slices such as the one flisek.',se iii l igfirc ` , Those modifi c ations, a 're also al plica le in processes fot making f hi if: rte pwduc:ti derived from pot lff, L.elrri, =~li~õ_tt>,r-yc., rice, o,it.s, raillet, and other 1 ui exmyiple these process Tnedihuations can be used to r:duce amr lainide tbrrnat o ire fabricated potato and corn products, cereals cookies, crackers, herd -pretzels, and breads; to naTric a 1.'e w. Note that the terms 'modified cooking step" and 'inoditied cooking unit operation .re meant to include not only l igu e '.s prior rt method for cooking potato dices but also prior art vineÃhods fbr preparing other food products in which ii. is desirable to reduc : t~ i l<tt pi e foWlation. In addition., flit, ter'PI "potoito-ba-,e l pieccs" is ti),it.1t to include both raw. pot-ato slices and 1 o rie ated potato pieces derived from potato starch or dou i.

[00 58] Each heating ,a op can be ac omp134lKd using ;':Inou" heatin+, methods,, For example, the first heatÃn ; step can comprise atmospheric #t').,'ii g v acuuin trying, I _tlciowave-tisisted frying. or bakingl lie first heating step, however, can alterriati wel`*' coca?prise any other method for cooking the product and lowering its "ErnstÃiie level with primary consider atioli 'Iv en to production efficiencies such as residence tin' w, energy costs., equipment capital costs and.
available floor space. When the first heating step ini,olveh trying the product., the first heating step is often called "par-frying as such frying only partially cooks the product until its rrioic lure content is lowered to some point near but above 3',-'n by weight. The second.
heating step can co'napris Vacuum ft + ingt loll' tempt atuic oven drying, 4 ati;Iil.il=n oven drying, or any naet-hod of cooking that ni aintalliscook:ing temperatures required b the second heating \tt=i?, I l.uw'Lvel.', caller methods can also he used to reduce molt ure content .:'Ink avoiding the los's?--J Ã1i 1a' xli1 ` ] c 3 t. 3'i7 3 i':l.iure conditions mo t i5 ?,'able to acrylaini ie formation as lone as the product temperature remains below ha, aerwiaindde fbnnaÃ'ion t~ mp .radii^e of about 120'C

'250'1'), The second heating step is often called' fini h tis in ' of `'finish-drying , as the moisture content is further reduced to the. -final desired level 1.0059] ft m odi:tslilt the 's ihin step 213 ,.aidl a the cooking step' fit tit t:I e_ process J.Ot in it lii4T potau.'s chips shown in F.Ieut 2, aetylam.Ide level in i:hc final product can bc reduced S.ig-nitlcantis: without aid ersely affecting product quality and final ch3,ia0te:=ristics. In one preferred embodiment, a ?c)Ãt_ii:~ ~Ã_1]1 1~Tlirtl ing process using fresh chipping potato `=s coinbinies traditional pe . linõ, slicing, and washin ; tf`ps with a modified cooking unit c),pe-ration involving par-Irsali at about IuS to about 182 C ('' Sit 60`'I ) for about: I mi_trutes, tollovved hi Oven-1 Z7, -15 drying bet o about '120'C (250T) until the chip niiui tti is lcvel is redia :d to about 14% by v eà lit. In tests using this preferred embodiment, acr larnid ~ s c is below 110 ppb are achieved, This pref.:rred embodiment achieves a balance between a high level of ac.r'ylamid reduction w%.Ab art acceptable chan- in p.oduct ll.ial tvAassoci ited with the necessary prcceS6 modifications. .l:lowever, other embodiments are possible. 1'i ."uIes 7a 7b, and 8 shov,, various r examples of combinations of-,,,.film Ãia diti. itiou comprising c:u.ntactiii;.
T`'.iÃr:# an aqucous solution _uld cooking Ãnod ifl rtions that r,dc.c [Anil it :i=s im de Ic.vcls ftom thus : les'ds rc' ultina f ';wi the >rior <iit .rncth 3e. s. 1 ut e .till lYk a tit?iil ici:\ lt~illAel 1;s c~l cal' nlorc: than i t ppb is reduced to less than :100 ppb. Although Figures 7a. 7l?, and 8 iinvoltie embodiments for processing raw Potato slices, the modified washing method'- used in thos :
z.rt ?;?+ : F11~ tr8,`, can also apply to other types of raw foods in which acrylamide reduction is desirable, such as sweca pota oes, yams, and plantains. Likewtise, the cooking modifications used in those embodiments can also apply- to other fried-food products such as tried tortilLis fried plantains, fried sweet potatoes, and tried yams.

0060 l'icur"e 7a depicts. the resulting acryl ariii.de lc ti els of potato chips made froi_r-i combininÃ., sever' l different embodimonts of a motto d washing step comprising contacting wid-j.
one par'ticu.lar embodiment. of a F1iodified cooking .top. The modified cooking step of Fi+gui a comprises partially 1-11-vying`par fdy:.ing ) potato slices at about -l 78 C
(35_ T) for approximately one to three minutes in a first heating step, uteri oven-drying the potato slices at about 1' O"C' (250 F) until the tamoistllre: content is reduced to approximately 1 by e~
fight in a second heatirig sop. T ' advantage cif par-trying tt?dlcAt ed by oven-drymy is that the lC?t --111o'i tur/'high-temp r ?attire conditions most favorable to acryla rard.e forrntafion can be avoided while still producing final products that are o g lnoiept c rlly similar to traditionally fried products. 1lowever r ten arc: o .era d ying can give the prodr cat a dr -ilrouth feel and may cause product scorchi g that is difficult to mask.

[00(1] l l-re Vertical of axis of the graph in Figure 7a shows actyl_tmide concentrations lia ?l.?ia. while the horizontal or x axis is lab led to show the parameters of each embod.iniient.o of the modified washing stop comprising contacting the potato Slices w"Ith an aqueous solution.

Each data point shows a pair of vertical bars'. the left bar represents acrylamide concentrations alter contacting and. par-drying white the r ght bar represents i-ictylai]'"ti:.le concentrations att:c-r oven-drying, Reading left to -right the first data point 71 of Figure 7: i, like that. of Figures 3 and 4, is {a base sample involving a t 'o to three minute water wash at ambient temperature, after Which the sample is, then atmospherically fried to roughly 1.i' 1= moisture by. weight. The second data point 7? is likee, the first except the sample is tried to about I. Oi ,'u moisture, Note that the first and second s raples 71, 2 developed thou 320 ppb : nd 630 pph of u r la-i-nirk respectively. '1'lae thud data pa ia.t 73 i xelvLs he s rr?etuvo to tlhree ri?Unut ib ent water wis h, 5- 1 but the sample is then par fried to slightly above 3' moisture and oven-dried to about 1.." '..t, moisture. The left n d right bars show that the sample exited the par-fvrng step with a relatively low acrv l4Faaaacf._ =oracentr itr: i? of about 65 l,~ l? and. gained less than 15 1 pb in the over?-drying step. The. fourth data point 74 Involves an aqueous solr.#t.ion. o;.n rÃ.sir-u water contacting the pot;_t-to shoes for a tine ri?inuÃe c:c?r?i:a::t time at about 60'C. it 401'3, followed by the par-fi iiig and civ rri Jt tug sty-1 s of the modilie:d cookin x unit olati at.ion l Ills five-minute, 60'C (1401"') contact combined vvi h the par 'tying and oven-drying stops resulted in an even lower final aL:t-s 1.aiaiid Lorice ntiafiirti Of l s than 40 pb, 1006' the samples contacted with calcium chloride Solution 5 76, 77 ;ill produced acr vlaataid . le els higher than that produc{:1 by- the sample 74 contacted with tire water for five foie- a es at about 60'C (14tt F;). However, the final Fcrv~lami e levels of all such samples were still below 80 ppb, ,vhicl? is s gni is ~.antly lover than the 32U ppb in the base sarriple.

illf?? The last data point 79 involves a 1.5 rr).mute contact with an aqueous solution cotaiprt la:a 1 `4) :-C-stein.. Interestingly, of she several Font ctin n.thods shown in I igaic ' this cone iCtin . iethod produced the . It?SS i .4.t t. ai 'euti mon oli acr7 lAarl-,ddt:. '1'1iis contacting method, laowLver, also required the longest c:.ontact'ti.rne of iii. various methods slit?vin in l'_Fgui' :
/a, Although using 1% 1 cys eiiae78 as the aqueous solution for =o:atactin resulted in. the lowest level of ac lawido in the final product, other- factors :must he considered, such as the cit:.t t of such a long contact time on product quality, as well as Ã_[) expense of rri reasir3 contact It, ('0064] Figure "h sho,,~ ='.s the. last six data points 73, + 4, 75, 76, 77, -78 of Figure 7 a on a graph .atth a n arrower %rc'r 'l:i$i)`i:f c con entration cafe-00651 In F igure 8, the results shown in Figure 7h have been no nalized to depict the aici'4'l.ara"iiile levels that Cor.ildl be e pectLd i ilae test sarr)plc:s 'crc. fried to a oistuo k cl slightly above :' /i) by weight and then oven-dried. at a out 120 C (250 F) to ao st aiid ardized moisture level of about 1.3% h e\c "l'it_ ['he Licr vlairiici :.l~ are norm ilir. ri iir t sri i)rw_iratic.i c e--,i.ubLd ;:il_?t 4 with. respect to 4. \\ '1 erà comparing the results 87, 84, 88 shown in Fi,;ii.ie 8 with those o sini.d ir G \pu'i.i)icnts 4143, =ih chawna w F x, Ure 1 o nC can si i that dividing tbt cooking unit operation into a fast high -teilTv atuu. huit4.ims ' 1cp and i sti_'oud 1o 'L:r kmi?Liatur:: heat1Ãn:0 Z--step 'Ti`?Ãaiu[ic.Lintlti% reduces acr4iari)ide levels- \\ h re is I>:iieiirc:
4 shows that lr iÃic in ,.i tiadiuomll ma:nuci to as stondaidlzed 132'.-;) moo titre level by vvCi 1)t should result in ri r la..t' i_k conc:critrations rarigmg ri>rii sli(-)kllw abo e l 00 ppb to over 400 a h. 1 igiir 8 -,how-,- that par-lry_ing and a tefi-zit inn to the same. taaclardi,Cd moistti:rc lc--el should rc.si:ilt ira s:ignrartii;:ar) I.

l ,'4w,er acrylamide concentrations under 100 ppb. The cumulative benefit of combining both a r2rodifiod n<ashi'ri4:' unit o erat'..tir'1 C.Ompr'i nnv a contactÃn step with ca ri)i)ilrtied Looki.i).tw .init operation is particularly apparent = hen comparing the 54'C (13) O'F)/5.min contact data point 41 of figrir 4 and the W (1401)'5-ininutc contact data point 84 of Figure 8 w-vith die huse data point 41 of Figure 4. As discussed above with respect to Figure 4, racreas ng.
the, contacting tim lror-ra 2-3 vililrut'.: to -? 'mid)iit s and hicrt,:)cing the coratae.tin$g temperature from mbic,nt to 54'C (130 F) causes the acrvlamide level n the final product to decrease from about .. }0 pph to approximately 'M 30 ppb. The second data pint 84 of Figure 8 shows that the ]aria:( acrylaTri de 1e gel caii be furtlacr r :.ducod to less than 40 pph -~,vhen a, similar ?-inn ute, nO"tY (140T.) contacting step is followed by a modified cooking unit operation involving par-frying and oven-drying .

.100661 Figure -shows the e i" ma i;c 1ncreas in final icrw latnide concentrations that results from using an oven-drying temperature above about 120'C' (2,550,f), In igurc 9, the test samples were contacted and t} en par-fried 117 [ e same manner as in Figure 7b, but the samples, were then oven-dried A. about 176'(-' = (330"F) rather than about 120'(' (250T): The final acry'lamid concentrations of the test samples Were then normalized to show the expected ter :-lamide levels upon reaching hy-~ eight which is the final moisture content that was reached rrtaC37`,i-7L17t 5tlriti{two-to-t 31Z<E11Titewit:lvvtilJ1Civ-Iis the first data point) .
Comp, ri-n4% the second data point 7 4 of t'i fure 1'13 ~~ itli the :L, ?i3dl clail<a point ; <l of Figure 9, for example. increasing the oven--dr y i g t~ ittpe at~ir~ from about 120'('. Ã _ 50 F) to about 176'(' ('550"1") :increased the acr lamide: concentration from shghtly below 40 ppb to approximately 270 p ,b, l"i?lai Oven-drying tempo atul'L: increase sin l ub ca '*d the at..o l4,i 3 dL L.oric ntrat z n, of the other test s_mlpt{ ; to draniaucal. lz. ine.re-awr, tom below 100 pph to o ;<:i' 500 ppb, Another test "ample (not shovvn.) v.a: \3'ashcd to reyrio` e \tu lace sitai-ch-; par-fiid at about 76'(' (350T) to a moisture content of between about 3 & by weight, and then dried in ai commercial Wenger oven at about 1,32"C", (270")) to a final moisture content of A out 1.3% by zyeig`ht result n III an s lam lc: level (if about 270 1p?l3. The results 93194, QS, On., 97, 98 slloN~,,-ri in Figure 9, as well as the results froin the test sample ov-eri--dried at about 1 ..'t .
('2710,F), thaws ll1.1strate the advantages of k Lping the cooking and "or drying temperature of ffl-it pro uct less than or equal. to about 120 C` (250 F) when the mois-lure content falls below approximately iR:
weig at. l his prir?.capie applies not only to raw potato slices but also to other foo ds, such as yams and plantains, and fabricated products derived from potato, corn, barley, wheat, rye., rice, oat's, millet, and other starch-based frr airs, [0067] Figure 10 charts the results and operating conditions of yet another embod.unetlt in which Potato slices were washed p¾ar ft d, and then oven-dried.. A control sample 101 was processed in a. manner similar to that described 3 ith respect to the Ns samples 71, ;1i+ z >rz in Figure'-/a- After about a 2-11 30 second .tmbient temp ta tug water w<t sh., i pl1owecl b .,M e!-Iv contacting the potato :slices with a .:Elute (_ 5%'%%) solution of sodium chloride for a iCti seconds, a Control sample 101 of 1.45 mm thick slices of p ele.d Hennes chipping potatoes was pa -fdd .d in oil having an initial teniperature ofabcut 179'C (35411 3 for approximately three minutes to 1.1%T moisture by weight. The control sample 101 had an acr i rip de conceTit.ra:ion of 640 pph, similar to the 6' )0 ppb produced in t c second bas : sample 72 shown in Figure 7a, The test se:impl~:: 1021 was s"-I;milarleashc:}1 and contacted like the control sample:
1Ã 1. Using a lava.

co nierc it Ifser., the test sample 102 was Then p , i-bird in oil ha\,ln ; an ii itiyii temperature of about 174'C (3450f,) -fcpr about three minutes un-61 The r oisti.i f.` cci nl.ent ` rei-ist. d to IS% b'6 ~ c ieht. The p.r r-hied test sample 102 Was he'll fix-fish-dried -for about usung an oven _ihout 1141 r' (230'F) until the rp1c stur-e. le L. decreased to 1.4'' ~ by v c,F:a'ht, t. ookh-. itt tii-is craw-it;..t produced pr-odut.t v ith a reduced `,,wrrlarnide t.r:tncera ation of 1610 ppb.. k- hich is rouch1 `
25% of the acrylanilde concentration Csf the control sample 101.

[0068_1 in i another set of tests not shot~m) similar to those: shown in Figure 10, potato slice;s undLt.w c ft a standard wash procedure, were par'-fried to about ' o moisture by, ss L r" rt.
and then oven-dried to toss than.bout moisture by weight. A control sample was washed and then tend ,_u i-ihout 179'(--', (3541-1) to r trnlslp.cd Tnoislure content of about 1 .3% bt"it.. iw:l t, resulting in an rice\latt-tide level or 380 pph, l loin s ei pat ti' iiag test rrirr pl s <rt al cpait;l;i'. t_' (754 1`) to a iiii"3isture content i.-.)f between about _? to about 5t~;%%
resulted in acnlarnide levels of approximately 64 ppb. The paF 1.i ied Product was then dE ie i.E a commercial W nggeT o w eM. at vaari.osus temperatures. It was shown that drying the par-tried slices at about 115'(' (2,40'F') to a final moisture Content of about 1. " : iircfistur = by weight Ina Wenger oven result :it ira at: r4l:a;raide lei .Is of 12,5 ppb. liter;siiia 1 did nr g, the par-fried slices at about 100'C (2.12'F) and under atmospheric or s ightl . less tl`aaait atmospheric_ presstirc. (13.6 to 14,6 p ia), even f6 r extended periods of=t.in (even is long a,,, .113-I S nimut%s 1, did Trot increase the ter't l araa.idc, lc.vc.l =
This etnhodiment. derrion\ttates ilia potato sliecs can be r ar-ftl d aat abom_rt 1 /T 'C'. ('54'F) to a moisture content oo between 3- 5 and then oven-dried at about 100` C J. I-) .der atmospheric or slightly below atmospheric press ure without increasing the ac.E yla bide levels beyond. ghat is 4-brmed in the par f-r ari4; t;p nation. To further reduce the concentration of aer'ylami le (buried in the cooked product, potato slices can be removed from the par-fry step cti'rtl3. a-loi: sture levels as I igh as I M.'4 by v:ei `ht, but removing the product too soon affect the final texture of the product. Note, hot ever, that this, method is not limited to raw potato slices tad can be applied to ot.hcr tried loud products such as, fried tortillas, flied plater i..at,, fried sweet pot 'a of >. and had -yams. 'The ad\'atata e of par-frying arid Then nicri dr}
int at about I 001:1C
(21-:: 1) is that the cooking unit operation alo.ne can be ii-iodlUL:d to sigiiif eairilk reduce, acrviamide 1 ii`i'?iÃa'iioni from above iOU ppb to less than about 70 ppE% the standard peelilli:s.l slicing, and washing steps need not be inodilled.

00691 In th .. set of embodiments i.rr uls iu ; par-tr+s tng followc.d b oven-drying, it is also possible to conduct the ov e'n-drying a. rider vacuuram, in order to enhance moisture rcrrioval. By oten drylii . under tacu.im, less time is required to dry the l?.r di..c.t to the desire= final niolsTurc content. Although it has been shown that oven-drying at or near 1.Ã 0 E
(2121') does not cause any raheasuriabl increase in acr\ lamhhidL levels. ovela dr iing at that temperature':.kes a relatively long time to dry, the product. hus vacuum oven-cl_t ing helps decrease the amount 01'time it takes t o r - prodtic-t to dry. I t alsro helps decreaase tlie amount of flute the product is exposed to aci s lzaFi7i le 1:7ita_ai.th temperatu es, should higher oven-dr ing to ~h is r< ÃE res be us : .

X007131 While Fiatres "fa, 7h. 8. and 10 depicted test results fromn, cotnbinin one particular embodiment of a modified cooking unit operation with several different embodiments of a modified washing unit operation comprising a contacting step, other embodiments and combinations are possible. For example,the various different contacting steps shown in those f.i tires can Instead be followed by a different modified cooking unit operation. Altc nat ,~ely, an I method for reducing atrylatmid:e fhrmatio can sine ply utilize a m 7dified cooking unit operation without mo Iif ing any of the other tinit operations. In another wt of embodiments of the invention. the second ofth. two heating steps of a'.modiicd cooking unit operation composes L ai ElEFi7i tthiish S.F'`<iitf rather than atmospheric frying, By finis -Ir4"#.n F7: li. S acau1n., the partially tried or cooked product e er;õing from the first h: eatinc' step can. continue to be fried, but at a iemp raÃur too low to 1o 1k ~, nilip irit-;F-iri C3FF1t of acr'ylamide, According to orle emboc1im nt.. the vacuum pressure should be such that frying occurs below about 12t3'C (2550T), Stich vacuum fini h frying can also be apt lied to other fried food products such as those derived from potaato. Corn masa, b ar'ley ei hcat, rice., oats, millet., and other starch-based gra."ins, 00", 11 figure 11 charts the results and operating condition", of several etr_Ãit~i~les Of a modified cooking unit operation .irtt olv ing par-frying f6limked by. In, the control 110 and test samples 111. 112, 113, 114, fkmrie s variety of chipping potatoes were peeled, sliced to about 1355 min thickness, and su `jec.ted to a standard 20-to-3'0-second ari blent-w1riperatur'e wash, Alter washing, the control s $ -Fmple 110 was fried at atmosp[wric pressure, in oil ha in- an initial tenth er;attire of about 177'i. (3511" fior about t?, 5 minutes to a moisture level of ().8-YNO by weight, producing aril <acrylamide concentration of 370 ppb, In Tests 1--4.all of the test sarliples 11.1. 112, 11 );. 1.14 were atmospheric pm-fried it about 177;'(' 't` Ã 351' i and vac uuni finish-fied at about and 100 millibars... but each was par-fried and vacuum firm Glr-lt"aed for different lengths of time, In Test 1 111, 121) ppb of ae vlamide were i-ta .F-fib fir, the test sample after washing, atmospheric par-frying for about 100 seconds to ' )",I:
.r#oistur by weight. and vat uur i finish-frying fo 44 seconds to Aout 0,7%
moisture by i eeight, l lae results, I' :sts 2.4 11'.2,,., 1 1 = 114 sl_iow that aervia fide level..
in the final produc Tr ani iti<: X11, decrease when par--f ry. p is stopped, and vacuum f ni h--dtyin' is :ommc. cc.d, before the .raic?isturC content decreases to t'.'% by weight. T gists '24 112, 113. 114 a11 I produced final acrylawide concentrations below 50 ppb. In 'test 4 1 14, am à ryl i~tittlf le el of only 13 ppb was achieved by Pal'-lrvtÃin to IW/i' moisture by ~ eight. then va.c iiF_[n-frying to about 1%
inti.toÃe b weigh. As can be seen fom the data, partially frying :slices to higher' moisture Content belt?r'e they are low temper:Ãtti#e vacuum finish-fried dramatically lover.; final '1G.r"';'l anndc coT ce.ntrations. This t loth{ d L- :-m also be à sed to reduce the final acr laÃnide, concentrations in other fried products such. ,.is fried tortillas, fried pl~.tiittains, fried sweet potatoes, cared tried yams, The advantages of 'vacuum l #idi ih frvln~ after par s.F'y'i .g to about.? 10"0 ra'rti'_sture by wei Ilt a o that the final stages of cooking can be ccm-,pleted La low temperatures without 'a.ttec;ti'ntg Product texture, and As ;.t-Ii t:ivcness at reducing erylamide formation can eliminate the need t r ;r modified Lashing step Cf;3T pri l.ri contacting flat pro ftii t with an aqueous solution. however, va0tÃtÃttt finish frying il allow for the final stages of cooking to be completed at temperatures higher than those that can be used when not frying under a v ic:trtiral. ~ Rile still providing a reduced a;:rylarnide. concentration in the finished product. It is noted that -i~: vacuum finish-fried riecl product had a }at~:.# color than the control sample, and transferring cooking prod ict from the par-1=ryin ; operator to the v. cuum 1 nish-:i ing unit at higher moisture leveis.ma impart a bland flavor to the product. It should be kept in t a:incl ti-tat tlj-e capital cost oa ti#arit t trivh t ,.itr ; equipment may b is greater than that 1. oven-clr'yi.rig equipment.

[0072] Similarly,, vacuum p a:r trying can be used in the first othe two heating steps CA a rtmc,dified cooking unit operation.. As arr example, one enibod irnent of a mc,cl# fled cooking unit operation _nwohies v ac:uun) pair 1 yi.rg to a taaoisture cs most near but above the threshold rr=ioistur : ievc:.l of tI-% by weight, then o en-clry ng at no greater than about 12W C ('25W 1) to completion By, par-1r inrT and z a_icr.turn, the product_ can be ried at lo%
=er t4rriperature; thus r s producing less r~c;_i=zarrr~r~ie. e , l~tattl~* -er'rr:ts r.:; t~~crr-cfryir-f at or .~ ,' (250T) c.i3~:ra~e:~
: i~_~ below about 1-20"C' ..t1 t.. that little tom) additional acrylara'ii e is fcirtrrcd during the oven dryirr tag . The ad-v,,antage of using vacuum par tryi.ng in the first of the two heating steps, particularly.
when doing io below about 1?tl t ? i)'' and even below about 140'C' (284'F) ~xlieri under vacuurrm, is that :little to no aciylami e will be t orrrmredin tlrefrst step, whereas par-frying generally proclt.tces at least orrie. level of amianlicle. 1-lowet'er, vaeuc#rri trying in the fimM bearing, step may create product.
w tin diffcn nt finished characteristics.

[007-3] For baked product lire: s', can involve :fabric.cted snacks or products such as c .roam.; cookie;,,, crackers, and l?r'etz ls, and bread, another embodirri,.ra o thc invention comprises a modit-1 =d cooking unit :oper=a'otion with a highe te.rnper'ature first biking step and ;--I
lc)R'~' t' t .nlpclritlir . second baking step, In the oooku-e. u rut op mason of this embodiment, die product is -first baked at higher t.c_rr p<r.tture d..racy e about 1210"(.
(250T)) until its moisture content is redueed to al o lit 4% to about I W;` ,, weight. The product is the oven-dri d (finish-dried or baked' at <1 temperature no theater than about 120` C (250 ) until tae desired moisture level, typically. about 1% toraboi.,t X) by ~wc l ll:t, .is a tained. For exam Ic, a convection oven can he used in the higher-temperature first heath? step to reduce product moisture WrItetlt to about IW'`ti by weight.. he oven may be. divided: into four heating zones in hicl he temperature is high st in the first zone and F_mdually decreases through the remaining three zones. A downdraft, single zone, coin ection oven may be used ill Ilie iow r4ternperarure second heating stets to complete the cooking process. Caller types of ovens, ho\~wevei, can be used i lr the tt 'O .hc ali.rl4' Stel)S of this embodiment. Also, the loser -te.m pe;rature second heating stqp of this pcartic.ular embodiment, like that of the r:Ilal?t~dim tliti involving. par-trying i plowed by, oven-dry. ng, can he performed at about lilt) t: (2:I2 F) and slightly below atmospheric pressure so that little to no additional acryltamnidc is fo ntae>d alter the higher-teI'i.3peratiire first heat ng step.

[0074] I.t tests using one example embodiment that involved i III :iF , ter alic ~' t}air first baking step and a.. lowi;= r tempen.Lure second bA.ing step. ILibriz at .:d potato piece,-,, w ere first baked at a ten pertattire above, about Il20 'C (2.50'1 ) until the moisture levels decreased to approximately l0 PS by weight, 'The pieces were theni_}lish-dried at :}boat 1 i0 t:_': ( 30'1=, i for about 10 minutes until the moisture content decreased to about by weight, Final acry,'lamide levels of about 100-200 pph A.\-.,ere reported, ,llt?, e er when several samples of partially-baked Pieces were hnlsh-dried at ibout 120'C (250 1) to about.
moisture by weight., acry l;antide levels of between 470 and 50 fq)b were report.-d.
F"(irthermorc, substantially hi ;clel acr lamide levels of between 460 and 1900 ppb were produced when samples tot: 1ar i.allti-baked slices were finish lliedl. at. about (2-70T) to about 1.6 2.2%s r oisture -by x These resales reemphasize the 111 pomance oà keopin', the cooking or drying-temp :rature of a cooking product at or below about {2501'during the final stages of cooking.
This principle appbb >snot only to tnc, Looking of -fabricated potato piece: but also to other fabricated prodt,Gcts el rived $torn potato. corn, barley, wheal,, rye., rig., oats, millet, and oth i st1arcli-hued ) liis pritlciple also pplie to Ãhe cor, in o rtr hinds s a :i, as tzrrs :ixrtl 1 1,.3r~tai_Ãr:.
grains.

[0075- in another embodiment of the inventi rn, rather than dividing the modified cooking unit operation into a higher-v.--t iperatur" e first heating step and a iow r t[mpet"cttt a"t second heating step, the 'modified cooking unit operation instead comprises Vacuum frying for 1 11 fl-le entire cooking process. Figure. ,. charts the re=sults and operating, co-editions of se.'v eral examples of such an embod.M ent. In Pests 1-4 121, 123, 124, various control groups. of 4zi rl~ient-t~.~r per~ture peeled, sli(ed, 1.45 rr m thick Hermes chipping potatoes were washed M

ate3 R)r bo'rit 30 seconds, then processeel. =]ri }r a standard continuous fryer, Tl-re fryer inlet oil temperature was varied within the range of about 165 to about l80) C "'329-356"), and the control samples were ti ied for about 3-4 m ntutet , resulting in <acryl:iirnide levels over 300 ppb. In contrast, the test samples in Tests 5-7 . 125, 126, 127 all produced eery lath ide cOncc:rstr ations below 60 ppb after loti .. t aril t trititt"e vacuum for" about 4 to about I(1 riainute at tcifi.larrat~ir r rÃi4xin from about 100 to about 140"C (2K2-'284'-'F. and pressures ranging from about 50 to about 100 millibars. As can be seen $roi`ir the data \ acuurn .r lnc at reduced temperatures drarnaticall ' educes the amount of acry'lramaaide tb-rfned, 11iii' heri:l)oxe, little to no icry'1<3riatde is 1{:7r'ri.ied when the product is v~tacauvri-tried a temperature of about 12 t,.'.

cook i.ng process. 'lasts 6 and, 126, 127, ~,,v that ,, l for instance, slat. .
(")501") throughout GI A. entire ',' cuum frying under bout 1,20'(" (2150 1") and it of 1ir sstire of no greater tl.,xi I00 rrm:ill:ihars results in -irtualk i.iti~l t .et~tlFle ]cs els t lcss than pp) of act' lrin idL:. 'I he Lids ar tag e of licit -, iirrxiQr about 120`' . (2 0 "F) isthat little to no a ca Ylami le is lornied whereas high-temperaftire par'-fr iing Cruses at least some acr v lta.iamirde to corm, fog 'sever, temperatures greater than about 12 WC (22 .50I can used .=when vacuum frying i vacuum is employe in hale still ac iewit ieduc. c ~t r~ laz ticl` cc~rtc ~ zitrtti i iti she l i~ishe etc>; t.
For exa m'ple.. in test 5 1' h w auruts frying at 1 Ott C' ( 84'F') produced a product with an acts larnicle content of about 5'.
ppb. c ri.VClr thisresult., it seems likely that vacixmn fnish frying or vacuum frying alone could produce pr odticts having loss than about 100 ppb crr, , 4arnide at tefriperatures kip to 1.43'C', (290'F), It should be kept n z ind, however, that vacuum frying, throughout the entire. cooking process may significantly alter product textur , appearance, and flavor.

[0076] For baled product lines, which c n involve fabricated ,tracks. cereals and other starch or do'uigh-based products as explained above, the modified co ?.king unit operation c' ..M

alternatively Comprise low-temperature baking for the entire cookin` roce s.
Lo\v _temperatE re baking can be perfortneu at or befo w about 120` ' ('25 0"1- so that little to no Icrvl amide is formed. Howweivet lower-temperature baking may create liglhtei eolc red..
products, zwhil. higher temperature baking may create darker colored products. l hus, the t.l plicabilitw of low-temperaturee bakirig cieperzds in part on the desired color characteristics of tbe Einar product.

[0077] A test was conducted to ascertain the level of ucr'ylamide reduction t "tat can be obtamimed b removing mor peel from the potato.
A.s ci sod li,:i it3, peel removal defined as the amount o.t peel .r'emov'ed from a potato. Prior art peeler` typically remove 60-7 0% of the potato peel from the potato prior to slicing, washing and frying the potato slices. S
stems 1 ?#'' peeling Potatoes are known ii-.t the art as exemplified b 1;' S. flat No. 4,83) 1,9'.12, assigned to ti-i. same assignee as the present inventiiorn. .Additional p &J. removal by such s stems also results in the remove al of additional potato flesh, A steam peeler can b,. used to cook flit o .aside layer of he potato prior to t utin the potato tcwa t?rush tumbler to enhairr t;r oval of flit peel awtiil.
minimizing flesh removal.

[0078] Sev~m l potatoes were peeled to one of ft cc peel removal levels. The first set o potatoes had mately i % of the peel removed t-rom the potato. Stated difÃ-erentiv, 27 %%% csf the outer periph rai surface area o l` the potato was made up of peel. A
second set of potatoes bad appro. rll<ately 88% of the Peel removed and a third set :had approximately 95% of the peel removed. Each batch was then sliced to at_lrickness of 0.0533 inches and fried in hot (A. The slices were then mt asu_red for moisttu're content and .acr'yl arnide levels.
Fib ll_re 1 3a depicts the se'e::c_o. 1 results of -that test, lest resultswere selected such tb.at the average of the moisture content ter each set of slices was about 1.614': by wcig t. ' l'he diamond shaped pointy in f 2:,ure U a r l~a'i= nt yail4'I<al39a la: and moisture content levels of the fried Potato slices having 7-3~ %% peel removed. ed. The square 1_aaped.poiratS represent ac,rylamid:e and taaiaisture content levels of the tried Potato slices having 88% peel rerricaved. 1 inalls , the triangular shaped points in F'igure 133a represent the act lami e and moisture levels of tla . fried potato slices lara~.i_ar 95"'.) peel removed.
As clearly shown by the data in figure 13a.. the fried potato slices having 88% and 951peel removed roalsistealtly had lower levels of aca l alilide than the fried potato slices having it#aly, ' 733'N, of the. peelremoved.

[00791 Figure ..1 3b is a graphical t ep esentation and trend line of th data presented in I #4;ure 1.3a. Because the average sat the moisture Contents for each test set was about 1.61% it was,not nec scary to no as7Lalizi. .ai'ryltrmie`_ e levels to i;, mpenstate test' 1'i oisi_a_ate l:#?i3tent:. As shown by Figure 1 3b, reducing the peel removal level, from 73'1,% to 8V/k, caused the ai rylamid ; level to drop l:rotar. an aver ag?e O r l 4 tc? 1 l t?l,l?: to tla 4#; 4õ f?.f 3 . ~E' i , lncreasin tiie peel rCIllo -al level from r c *eta 95% 95"' i?t] k` reduced lz1:ei1 1 l 1. 5. ~3",. ~#aet'4~tst3?s the Y)c%=.

88. ,x t 1L-' :.i' aZL-' level by ia11iac_ eli~t(?.r?~.: ,.: 1 removal level from 7-'I%-((,s 95. ? caused the cae vl :ami e level to drop from an a er"a ce of 214 p13h to 146 pph.r as docrease of 46,61%,i'%.

[0080] Because potalocs are often oval and because out r= ?eripheral potato sure aces often comprise concave Wctwiis, es "Jeciall .' in areas of the eye of the potato, increasing the peel rerrioval level above 88% and especially above 95% can result in changing the shape of the peeled potato from oval to round and can result in substantially hi ,,her levels, of pull? kiss. For example, the table beJlo d -1.?1.ctc ineasurciututs of icsulttnit Pulp loss as, ~a conscqu .F.,LC i-) p `cl ren-,Iov,al. The Pali) loss zs shown as a mass percentage o the potato .owe the 3.22'-%'% loss coin-monly associated with a 73% peel removal level.

RL moved Additional 11ii1j) Loss (mass %) r' 0.0'%
'? 0.

0.81 78 1. 6 -----------------------------------------------------"9 t . 8 2.1 r 8'2 2.87 _s 3.2.1 ----------------------------- - - - -------------------------84 =T 56 'S 1,9n ------------------86 4, ------------------------------------------8; 4.69 ----------------------------------------------------------------------- - -- - -----------------------------------------------------------------_5.08 ---------------89 5,49 L --------------------------------- --------------------------------------------------------------------------------------------------------------?91 1. 6,2) 8 -------------92 .2 9, .17 -------------- - -------------------------------- -------------------------------------------------------------------------------------------------------- ---------------------------------94 7,63 [00811 In view of the diminishing returns of a rylainide reductions and in vie ' of the environEk enta] irnpac of pulp loss.. in one r bodlnwn.t, the level of peel removal is less than about 95'%' ~ and more preferably Iess than about 881. In one embodiment the peel removal is at.
5 least about 80% and i ore pi'eierahly' `i 415.'een about 80` 0 and about I00%`%. In one :into dinient, the ped r'moval is be'Ãiveen about S0% and about 9M more pr t.rabl b'=t,~-cen about SO% and about 88%.

[008'2] in addition to it b .ing diseok :r ;d that Potato peel l re ponslbf..to.r the rr 'f'C.renti,il f rniation of acrylamide, potato slices with detects. have also been found to be linked 10 with 1rrghe levels of acrylamide w'.en fried in hot oil e.g. tried in oll having an oil to laper'aatu-re t2tygr dater than about 280T than potwo slies 1iaving no poaFa:to defects. 1 po :ttf? slice h4ts'111 no d..tcc`ts is '.a slice ha vino in e' enlti Loldeir. lair t?.n. its el'itire Surface area it3e t -y in > Potato defects are w-cll ktrt, ;~n to tree ;:kill d in the an and such defects .include, but are not l mit.ed. to.
(LIMe3 dr rot, sokib_ Ali llo,4 Earl, ' . r e e n i n g ? hkz1 \ t :_i_ R}~r'i}trtril , ~~1'ai3 ,<v, leaf roll and s u g a r r 15 defects, Additional flail on defect ft urid in potatoes, including ;;
listing of _.udt detects, Carl be .found in 1.rifÃirni.ati n 1_tudleti.n '2,05 tidcd :Detection of Potato '.1 Ã:# err. Dl:,ca es and Deft.
published by the C. car:r ell University Department u P1 :arat 1' itholog - on tlh :.u-t vvebs:1t at slit 1:: 1t ? ;~1era1 x~ lri L tit t`i~ t ri 1'i e ------------------------------------------------------ ~tÃ_` its) i j :ti. r .`..,:i,'. I his ril.tEl.E'.t113ti.f:lYa bulletin Ãs inc or'poi led. herein by r'efi.renc ..

(00:5 ] Several -f:ried potato slices having various defects, were fried to ai Y ioisture content belt. ~ ? by weight in hot oil and analyzed for l ve.ls of acr y-lamide., the results are provided in the table below --------------------------------------------------------------------------------------------------------------------------- - -------------Fried Potato (.hip 1 of .cra , l arrti.tL level Ã:pp? rs Zebra 4435 --------------- --- --------------7 Black Le-, 1,081 Sprout 19 27 G-ree.n. 18 16 ___________________ - `` ___--ki 5}1 --------------------- --- ----a_t#t 1?64 --------------------------------------------- --------------------------------_______________________________ f00841 Sugar dekctss ire not typically- rei-taoved from product streaia s prior to packaging.
Interestingly; chins having the highest acrylam.ide level: because of sugar defects have not l3istoiic:aally been ala e d as Lo.mstuner defect, beccruse dhcse defect, h.v . prcdoniinantly tight to -hrownish colors and ther'e-sre are not considered unaa,c.q)table. Raatlhc- r, detects such as, rot.
iirid blaackl ;, and sprouting which have predominantly black or ver dark colors are t1 v types of potato defects most likely to be removed prior to packaging.

[0088 As L. en-.tpfified by the d ,:tit atbo e, -remits al tOdLtecti .he'd potato chips from the paL ka .,rtt~ proccs Can help to ;>ubstatrntiall\ cdutt the as craft lc;a el o f ids'( mud. .ta a l'.o I
product serving, i 1ttns iii#~:31114' in one cmhodir,T-Ina ot;'1h3.:
invention_ potato slices, having a defect known to be chanatter ,,tit. of 1hi..-h lesek of iti taini3de are it. t rn .d prior to packaging the.

lood products,. As used laeie. n, a potato tfice has a detect kno-s i to he t.
hairiia.teris-o tO as hi ph level of am.lam.ide .i:f the aciylsti .ide to ceattratiÃ3.n due to th2e dcfcet is afore than tesi: t. ibe level of a non-defect.iv potato slice thermally processed under the same conditions, 'l-bus.., a slice having a sugar defect is one that because of higher than torn l sut ar content wilt produce i-finished f?(:)tato slice ha-vin g more than oA ce the level of acryla ide as a potaÃo slice having a normal sugar content that is If-kcr'.i`Ã all processed under the 4ai.ne conditions.

[0086] Removal of such defective potato slices um, be achieved by ? sing a potato defect detector do wnstreeam t?f the fr-" r to remove deice tive potato slices prior to the packaging proc ess, A sorting apparratus. such is an 40 Optyx 6000 aiva l blie ;.rain Key Technology y, Walla wall"', W;aIshingtora, US, can be used. Rejected fried slid., can be routed back upstream of the sorter in a ,recyt stream to ensure the rejected fried slices have defect.
Such configuration provides an opportunity to ensure the Potato slice is detective prior to routing the slit,'" to a waste stream, In one preferred embodunent a recycle stream is pref. bly not '.1sed, and -rejected . _ ied ,slices, are sent directly to a waste stream, [008 ] As discussed above and as dem nstrcted by Figures 5 and {gin moisture content. can be a uset"01 additional parameter that can be adjusted for the reduction à t cryla "1:ià e formation in the final product, such as a fried potato chip. In one :,mbodinaent_ the <i .i lariiide level is decreased by employing a plurality zf acry'lr.tmide reducing strategies to preserve the orgainolep-tical properties that consumers have become accustomed 'EC's irn prior art Potato chip, that axe f:iie to moisture contents at or below about 2b v a ci;Fla#: eviEl c_tttE .ie.lding additional unit operations in the dehydration, cooking, or ft y rig step.
Conseq:.tentk.., n one enab ?d.iriiei.it, a method for making ai fried potato chip corapii.e the steps of peeling a potato to make a peeled Potato f1.:4 %%ii of at least about 80% of the peel rerrm-,,v e.d, slicing and washing he potato slices, and frying the peeled pot 'tot at ambient pressure to a ono sture content of bets ,een about 1.3% and by 4~~c r.,3:rtef r.-icire: 1?)~efera~' ili: bet en about 1..~. s~ and :<.,~c?tit 1.i)n . ~~ ~, about about about 1.8% by i ght., ryt% 1.

wherein said frying step occurs in one and only oi-ic fart er.

[0088 1 I .Ti one embodiment, a continuous mutt zone fryer can be used. A.
continuous rla altiryzone fryer ,an have two or more hot mil Inlets ets where hot oil is Injected after exiting a heat exehwiger having an outlet tell) pà rare:}re. The outlet temperature of the heal. Qxchautger closely aligns with the iipstTeam or Inlet te._}Tip?er'ature of th.e fr'er. .onsequen-fl , csr purposes herein, the oil temperature at the à xchanger outlet is EI e santre as the i} ie:t fryer to . per'ature. As IxAato slice.
are placed into the fryer, the slices are heated and the l.i) f.sture within the dices begins to evaporate. There is a temperature gradient from the f y '.r inlei to the fryer outlet. At the fryer outlet, the oil is removed from the fryer and routed to rltc. heat ex hanger to be reheated placed back into the fiver inlet, The heat exchanger inlet Temperature closely }lign.s ,vilb. tile outlet temperature of the fryer. Consequently, tor purposes herein, the oil temperature it the exclianeer Inlet i s the same as the outlet fryer temperature, The outlet fry or Can be controlled by a number of factors including the inlet fryer temperature. and the product load Placed into the fryer. Ill: Ã ne etnbodiment, the potato "Lice s are tried in the fryer such. that the fryer outlet temperature as held betI i ert <ai?Ã,irt 2r?:a'l and al.-bout 30-5`F, This is an advantageous temperature range as it Gallows for reducing &L r" 'Icllt,lÃtt 'ti?i'adlttri?}
while still promoting a Cris p chip without a soft center. Chalet fryer temperatures _ibose 05 F result in undesirably higher levels of acre lamide while outlet try r temperatures bolo aai?i>aat '~?. ` 1 resin#. in compromised oraaanoleptical proper'ti `ss. For exa711ple., the c liters of the fried chips can b comm'ee sob at .lower -trier outlet temperatures and. are undesirable to consumers.

[0089 1 In one embodiment, after exatrai g the fryer, the fried potato slices are then routed to a Sorter Which is programmed to r"elno,, potato defects, inncludin but not IUri3teed to, defects :elated to zebr,:t sugar, black leg, sprout, x.leen, bruise, and rot defects.
'The sorted potato slices can then he packaged, [0001 ] The data presented in the table below illustrates how one embodiment of the present invention can be used to lower the level of acrylamide in a fried potato chip. Although the potato slices had similar asparagine levels and peel levels, the "test"
potato slices were fried to a slightly higher moisture content using lower fryer temperatures. A higher level of potatoes having defects described above were removed from the test samples than from the control samples. These process changes resulted in "test" fried potato slices having less than 40% of the acrylamide levels of the "control" fried slices. It should be noted rejected slices were collected simultaneously with the non-defective slices in the "test" run and the defective slices were also tested for levels of acrylamide. The defective fried slices had over five times the acrylamide levels as the non-defective fried slices. Thus, it is apparent that defective fried slices can have a substantial impact on the average acrylamide levels and the removal of such defects helps to lower the overall acrylamide level in a packaged food product. It is also interesting to note that the variation in acrylamide levels was substantial. For example, the rounded acrylamide levels for the control samples were 369, 402, 460, 660, 788, 852, 827, 713, 596, 589, 410, and 374 ppb.

Similarly the rounded acrylamide levels for the "test" samples were 186, 210, 225, 212, 211, 379, 226, 210, 209, and 119 ppb. While the standard deviation for the acrylamide levels for the control samples was 181.9, the standard deviation of the acrylamide levels for the "test" samples was 64.03. Below is a comparative listing of recorded data, which illustrates the comparative advantage of one embodiment of the present invention:

Parameter Control Test Moisture (%) 1.04 1.46 Acrylamide (ppb) - 586.7 218.8 Product Acryalmide (ppb) - Not Tested 1126.8 Reject Asparagine (ppm) 3681.4 3680.9 Reducing Sugar (%) 0.01 * 0.014 --- -- -------- -------- -- .................... "
l: N Q Sts;t{ 69,;I'2?
-------------------------------------- ............................. ....
...., .............................................
Not 1t~;t:L l (): S6 --------------------------------------------------------------b ')6M
-NotTested ---- ---- -----1i~} S5yl X44 ---- --- --- -To (F) )4,6 3 0-3-31 .............................. ------ ------------------------------------------------------ - -------- --------Oil of fried slice 35.3 36,19 ----------------------........ --- ---- - ---l1tc irtf{i 3iit i 1134`h 1 60001 5070 I =
Pe.el to t;{ 70- f 5'i;O' Slice { .E?iCi~i14 N i_ S,.iiti -files 1L 10 0091 1 *Redu .ing Sugar content of control wasotily measured to two decimal places.
,(10921 1 {7i invention. contemplates combining th te.,cis::hà nn, heroin '`{
ii 'i rog.,-u 'd to s-aaious unit operation t anipulations in order to aC iev'. a desired ;cr41aniid level in the end product t Tong 'it1'i the dcsi..red c:iid prodUtt G11 ii' i=#4 1 1E `, The Lori(>.i'{iaL1on used d p 1d on the, starting pros :uct and the desired end product and. can be adjusted by one, skilled in the art purl ant to the teachings herein. l he + ffecà of PH on tier;'1:m-l de tbnaiaition 1s anotk r 11"'Ictor that may be con iderod and combined with the teachings hereirl.

[009 11 It should be understood that changes in the of the final product.
such as c l <irint. , in color, taste, 4u.0 consi.,tc:u4 ' an be ad*w\ted by 'ti'it6,,:lus mean.. 1'oi exao' 1 :, 0 color characteristics in potato chips can be cadjt:`;Eu,l by controlling the amount o `Lauai'\ in the starting product" Some flavor ch,aracte.risti:c s can be chat ed 1_S the addition of va v ~lririw agents to the end product. The physical te:&tLiT-4: of 0--w product can btu adjusted by, for example, the addition of leavening agents or various e1'1 ulsifiers.

(0()941 While the in enion has beets parti cul shown and described with 1e 1'i;r'c nc.- to .15 one or more, eirhodinic tii'a .ii i 11 b:5 ai r rstuod by those. 'd ili l in the art that varioitl-appioae lie.; : to the reduction tat' act-y . iititd`...oi t{1%I'.in ill pioces d mod ; b ' inaete:= without Eii partiritw i't11''I the s1:!l:i':1t T.iL1 scope [` tilt :i1 z ;li: oti For L m1?1plu. ? -lffl the p.i=ot. ss llsaa hui;=.u disclosed herein iti:a regard to potato prod icts, tote pi:iza:e ss in also be used iii processing o{

food products made from dõ oni., barley, wheat rye, rice, oats., i iil Ie ., and other starch haswd grains, in addition to potato chips, the: i nv'entiwi can be used in making corn chips and other types of snack chtps, as wef as. in coi ak, cookies, crackers, hard pretzels, breads and rolls, and the broad ng for breaded meats. In each of these foods., the pr : enl invent fxn s method 'or manipulating one or'.r ore unit operations can be eonib ned with other strategies E3i 11--le reduction of aicr' larnide to produce an accm:.ptable acrd lainldi. lcv i 's itbout.
adversely affec ing the taste, color, odor, or other- char t :riser .: of an individual fbod.

Claims (11)

1. A method for reducing acrylamide formation in thermally processed foods, said method comprising the steps of:
a) removing at least about 80% of a potato peel from a plurality of potatoes to make a plurality of peeled potatoes;
b) slicing said peeled potatoes to make a plurality of potato slices;
c) frying said potato slices at ambient pressure to a moisture content of between about 1.3% to about 2.0% by weight to make a plurality of fried potato slices;
d) identifying defective potato slices by analyzing each of said fried potato slices for a potato defect known to be characteristic of a high level of acrylamide; and e) routing said defective potato slices to a waste stream.

2. The method of claim 1 wherein said removing of said peel at step a) further comprises a peel removal of between about 80% and about 100%.

3. The method of claim 1 wherein said removing of said peel at step a) further comprises a peel removal of between about 85% and about 95%.

4. The method of claim 1 wherein said moisture content of said fried potato slices is between about 1.4% to about 2.0%

5. The method of claim 1 wherein said frying at step c) comprises frying in a fryer having an outlet oil temperature of between about 295°F and about 305°F
to a moisture content of less than about 2% by weight.

6. The method of claim 1 wherein said potato defect comprises a sugar defect.

7. The method of claim 1 wherein said high level of acrylamide is at least about 1000 ppb.

8. A method for producing thermally processed potato slices from raw potato stock, said method comprising the steps of:
a) removing at least about 80% of the potato peel from a plurality of potatoes to make a plurality of peeled potatoes;
b) slicing said peeled potatoes to make a plurality of potato slices;
c) frying said potato slices in a fryer having an outlet oil temperature of between about 295°F and about 305°F; and d) removing from said fried potato slices any slices having sugar defects, thereby producing as the remaining slices potato slices having a reduced level of acrylamide.

9. The method of claim 8 wherein said removing of said peel at step a) further comprises a peel removal of between about 80% and about 100%.

10. The method of claim 8 wherein said removing of said peel at step a) further comprises a peel removal of between about 85% and about 95%.

11. The method of claim 8 wherein the moisture content of said fried potato slices after step c) is between about 1.3% and about 2.0%.