CA1178107A

CA1178107A - Process for the production of a food product by sintering

Info

Publication number: CA1178107A
Application number: CA000387828A
Authority: CA
Inventors: Walter Rostagno; Alfred Morand
Original assignee: Societe des Produits Nestle SA
Current assignee: Societe des Produits Nestle SA
Priority date: 1980-10-31
Filing date: 1981-10-13
Publication date: 1984-11-20
Also published as: DE3170157D1; AU7628881A; PT73911A; PH17362A; SG53184G; JPS6328582B2; GB2087788B; EP0052728A1; JPS57115170A; DK161179B; DK161179C; ZA817064B; DK457481A; NZ198618A; GB2087788A; CH644738A5; ES8302428A1; AU543841B2; ES506706A0; EP0052728B1

Abstract

Title : A process for the production of a food product by sintering Inventors : Walter ROSTAGNO
Alfred MORAND

Abstract The invention relates to a process or producing a food product in the form of an individual article, particu-larly a bar, by sintering a powder-form starting material.

To carry out the process, the powder is introduced into the cells of a mould, lightly compacted in the cells, heat-treated in a furnace for a period and at a temperature such that the individual particles melt at their surface and adhere to one another, after which the articles are removed from their moulds and cooled.

The process is applicable to culinary products and to articles of confectionery or chocolate. The articles obtained may be coated.

Description

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`- 2 -This invention relates to the production of food products in the form of individual articles, particularly salted culinary products or articles of confectionery or chocolate~
S ~ore particularly, the invention relates to the production of compact individual bars from a powder-form product.
Existing products are generally produced by extruding and dividing up a so-called ribbon or by the cold compaction under high pressure of powder or even by the moistening of a powder to convert it into a tacky mass, rolling the mass thus formed, dividing it up into individual portions and then drying it by heat treatment, the heat treatment optionally being carried out in vacuo to cause the product.to expand.
These processes are expensive and difficult to carxy out:
- the end product lacks homoyeneity because of the dificulty Of uniformly dispersing the liquid, - the economy of the process is poor because the moistening of the powder to convert it into a tacky mass necessitates subsequent evaporation of the water introduced, - the fact that no mould is used means that compaction has to be carried out under a very high pressure to ensure that the individual products retain their shape and are "self-supporting", this operation frequently being followed by expansion in vacuo to enable the structure to be aerated.
It has now been found that moulded articles, particularly ,! ~

~L~7~ 7 in the form of bars, may ~e produced from a powcler-form starting material by a particularly simple process which does not have any of the disadvantages attending known processes.
The presen* invention provides a process for the production of a food product in the form of an individual article, particularly a bar, from a powder~form starting material which is capable of being superficially softened under the effect of heat and which has a high degree of fluidity, which comprises introducing the powder into the cells of a mould, lightly compacting it in the cells, subjecting the compacted powder to a sinteringtreatment in a furnace over a period and at a temperature of the product such that the individual particle~s superficially melt and adhere to one another, removing the articles from the mould and subsequently cooling them.
The constituent particles of the powder should be capable of melting superficially and of fusing to one another so as to form a rigid structure which does not disintegrate after cooling.
In the context o~ the invention, a "powder having a high level o~ fluidity" is understood to be a powder of which the constituent particles are dry to the touch and non-tacky and flow freely. The moisture content of a powder such as this is generally its natural equilibrium moisture content at which the product used is normally packed.

Provided that it satisfies the above-mentioned requirements of superficial melting and fluidity, the powder-form starting material may be selected from a wide variety of carbohydrate-containing food-grade materials S used either individually or in admixture. The category of culinary products includes for example vegetable, meat and fish extracts, protein hydrolysates, yeast extracts, cheese, milk, cereals, starches, particularly modified starches and dextrins. The starting material may also contain other ingredients such as spices, flavourings, colourants, fats, sugars or salts.
The starting materials for articles of confectionery or chocolate include, for example, fruit extracts, sugars, maltodextrins, cocoa, coffee, chicory, malted cereals, lS milk and fats. These materials may also contain the ingredien~s normally used in the production of confectionery and chocolate, such as flavourings, lecithins, boiled sugars, honey, caramel, nougatine, expanded cereals, dried fruit or size-reduced or whole candied fruit.
In general, it is preferred to use predominantly carbohydrate-containing starting materials characterised by a fats content of less than 25% by weight and a moisture content of less than 20% by weight.
The particle size of the powder naturally has a bearing upon the texture of the produc~. The finished article will be more compact, the iner the powder used.
Particles ranging from 0.1 to 3 mm in diameter give . ,, satisfactory results, To carry out the process according to the invention, the cells of a mould are filled to the brim with powder and the product is levelled by means of a scraper, the individual cell forming both the mould and th~ metering unit ~or the product.
The powder is then compacted by the application of a pressure corresponding to between 1 and 8 kgjcm2 at the level of the product by means of a piston adapted to the cell of the mould. The obiect of this operation is to bring the individual particles of powder into contact which is necessary for the subsequent roasting operation and the final structure of the product.
Alternatively, the moulds may be vibrated to ensure lS good contact between the individual particles of powder, this operation replacing the compacting operation.
The following so-called roasting step comprises heating the compacted product for 3 to lO minutes to a temperature of from 45 to 120C in a tunnel furnace. The duration of the treatment and the temperature applied depend upon the volume of powder to be treated, its nature, its composition and its moisture contentO The object of this treatment is to place the powder in a state of superficial fusion so that the individual particles melt at their surface and adhere to one another. The temperature of the furnace depends upon the type of apparatus used and is generally in the range from lO0 to 300C. During this ,~

8~

operation, the product loses 211 or part of its e~uil.ibrium moisture in contrast to the conventional processes in which the product is first moistened and then dried by heat treatment.
For reasons of effectiveness of the process, it is preferred to keep to a thickness of the product of approximately ?0 mm to ensure that there is a transfer of heat which gives a product of homogeneous textureO
At the outlet end of the furnace, the products are removed from their moulds by inverting the moulds which are recycled. The articles are then cooled, in particular to a temperature below 25~C in the case of articles intended to be coated with chocolate.
The coating consists of one or two layers and forms a protective barrier against the penetration of moisture and against fat-induced whitening. Th~e products thus coated are then packed, for example using the flow-pack system.
The accompanying drawing d.iagrammatically illustrates one example of an installation for continuously carrying out the process according to the invention.
The Figure is a simpli~ied diagram of the installation.
As shown in the drawing, the installation comprises a feed hopper 1 which distributes the powder into the cells

2 of moulds 3 fixed to a conveyor belt 4 circulating step-by-step (5 to 15 steps per minute) in the direction of the arrow f. After or during filling, the mould is levelled off : ;

.

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by the scraper 5. The moulds are then directed to a compacting press 6 which comprises stamps 7 adapted to the cavities o the mould and which makes a downwardly directed compression movement during the stoppage time of the conveyor in synchronisation with the step-by-step transport of the moulds (arrow d)o The moulds travel through a tunnel furnace 8 equipped with one or more heating zones.
At the outlet end of the furnace, the product is removed from its mould at the station 9. The moulds are returned to the f illing station along a path which has not been shown.
The articles removed from their moulds are then cooled in the tunnel lO, subsequently coated at the station ll and wrapped at a packing station (not shown).
The process according to the invention is illustrated by the following Examples in which the values express ratios by weight~
EXAM
A powder containing the following ingredients: cocoa having a fats content of 21~, malted cereals, skimmed milk powder, butter oil, sucrose, lecithinc mineral salts, vitamins, vanillin, and having the following composition:
proteins 13.0 carbohydrates 69.8 lipids lO.l mineral salts 4.6 water 2.5 and the following physical characteristics:

~ 8 --pzrticle size (mean diameter) 0.2 mm apparent specific gravity 0.4 g/cc is treated.
This powder is distributed into the moulds and compacted under a pressure of from 1 to 8 kg/cm2. The initial thickness of the layer of 17.5 mm is then reduced to 13 mm. The moulds travel through an electrical infra-red furnace over a period of 4 minutes, the furnace being kept a~ 150C and being provided with a fan for the removal of steam. The articles are removed from their moulds by inverting the moulds which are returned to the filling stationO The articles are then cooled from 70C
to a temperature below 25C over a period of 6 minutes in a tunnel.
The cooled articles are coated in two stages, first with a layer containing the ingredients sucrose, vegetable fats, cocoa powder containing 13~ of fats, skimmed milk powder, lecithin and vanillin, this layer representing S0~ of ~he weight of the demoulded article. The article is coated with the liquid layer at 40C and cooled in a tunnPl to a product temperature of 23.5C. A second layer is then applied using the same quantity of coating as before heated to 4CCo The end product is cooled to a temperature below 20C.
Alternatively, the first layer of coating is formed by the above-described coating and the second layer by milk chocolate containing the ingredients sucrose, whole milk , ~71!~

powder containing 2~ of fats, cocoa butter, cho~oiate liquor, butter oil, lecithin and vanillin. The coating is at 40C during the first stage and at 29C during the second s~age of the operation. It is also possible to use a double coating of milk chocolate at 29C~ From 0.5 to 1% of sorbitan tristearate is advantageously added as anti-w~itening agent to the milk chocolate. A ccate~
bar weighing from 25 to 30 g is t.'nus obtained~
EXAMP _ The procedure of Example 1 is adopted fox the production of a coated bar of which the centre is formed by 44.1% of the powder a~cordin~ to Example 1 and h~ '.8~ of whole roasted nuts, the coatin~ ~e~n~ formed by 4~ of mi.lk chocolate as in Exa~le 1.
EX~IPI.ES 3 to 6 Tlle proca~lure of Example 1 is adopted ~or the productio~ of the follo~ing coatecl bars:
E~le CentrP ~.cating 36S % dried coconut 29.5~ 35~ of miLk chocolate as in E~le 1 sucrose 29.5~
sorbitol syrup 6 %

4 70 % m~re accordmg 60 ~ 30~ o milk chocolate to ~le 3 as in E~le candied cherries 10 %

52.2~ instant coffee 1.3~ 47.8~ of miIk chccoiate pow~er as in E~le 1 instant chicory 1.1%
}~er malt extract 9.5 ' p~er ~L~7~ 7 sucrose 17.55 whole miIk21.35 ~er containing 25~ of fats cocoa ~er 1.4 %
containing 13~ of fats 6 47.6~ sk~d milk 7.6 ~ S2.4~ of milk pow~er chocolate as in glucose syrup 1.9% ~le 1 cont~ng 40 of dextrin equivalent whole miIk26.7 pc~er.contalrJng 25~ of fa~s malt ~act 11.4 %

X~MPLE 7 The procedure of Example 1 is adopted for the confection of a centre from a powder containing;
skimmed milk powder 30 %
sucrose 40 vegetable fats (Biscuitine N ( )) 10 %
malt extract 2 lecithin, salt, citric acid, -f~avouring 1 ~
water 17 %
The centre represents 59.4~ of the end product and is coated with 40.6% o a layer of the same milk chocolate as in Example 1.
EX~MPLES 8 to 34 These Examples show that the process according to the invention may be applied with satisfactory results to ~ ..
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~ 11 powders of a variety o~ origins.-The following Table shows the conditions under which the centres are produced:
Example Ingredient Compacting Duration Furnace Product Roasting No. pr~ssure of the temp. temp. results (kg/cm2) furnace (C) (C) (mins) 8 malt 2.5 5 100 68 goad 9 dextrose 5 5 150 85 good sorbitol 5 5 75 53 good 11 freeze-~dried 3.7 5 120 83 good instant coffee 12 Pmstar ( ) 2.5 5 150 90 good sugar with a m~isture content of 1~ (Amstar Corp. ) 13 Biogerme ( ) 2.5 8 150 90 good (Multiforsa AG) 14 Sugar Puffs 1.3 5 100 62 good mould release difficult toffee (skim 2.5 5 100 59 good med milk +
glucose syrup with a dextrose equivalent of 40%) 16 chicory 2.5 10 120 80 average 17 lactose 3.7 10 150 91 average 18 skimmed milk 3.7 10 lZ0 85 good 19 miIk containing 2.S 10 120 87 average 25% of fats milk ch~colate 1.3 8 120 97 go~d 21 pla m chccolate 1.3 8 120 96 good 22 fruits (fresh) 2.5 5 120 75 average 23 honey 2.5 53 75 48 tacky 24 dry cheese 2.5 10 150 101 average ch~ese ~ lactose 2.5 5 100 72 average 26 acidified milk 2.5 10 120 89 average 27 dehydrated pea 3.7 8 150 91 good ham soup 28 dehydrated 3.7 5 120 72 good tomato soup 29 dehydrated 3.7 5 150 91 good potato (30~) ~roth dehydrated cereal 3.7 5 150 90 good soup 31 Cvomaltine (R) 3,7 10 150 102 average (Wander AG) 32 Prontovo (R) 3.7 8 ~150 91 good (Wander AG) 33 Dawamalt ~R) 3,5 5 150 90 good ~an~er ~G) 34 Soya malt (R) 3.7 3 130 67 average (Morga S.A.)

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for the production of a food product in the form of an individual article from a powder-form starting material capable of being superficially softened under the effect of heat and having a high level of fluidity, which comprises introducing the powder into the cells of a mould, lightly compacting it in the cells, subjecting the compacted powder to a sintering treatment in a furnace for a period and at a temperature of the product such that the individual particles melt at their surface and adhere to one another and the powder has a particle size of from 0.1 to 3 mm., removing the articles from the moulds and cooling them.

2. A process as claimed in claim 1, wherein the powder is compacted by applying a pressure of from 1 to 8 kg/cm2 to it in the cells of the mould.

3. A process as claimed in claim 2, wherein the sintering treatment is carried out for 3 to 10 minutes at a product temperature of 45 to 120°C.

4. A process as claimed in claim 3, wherein the powder has a fat content of less than 25% by weight and a moisture content of less than 20% by weight.

5. A process as claimed in claim 4, wherein the starting material is a culinary product selected from vegetable, meat, fish or yeast extracts, protein hydrolysates, cheese, milk, cereals, starches, modifled starches and dextrins.

6. A process as claimed in claim 5, wherein the staring material contains one or more additives selected from spices, flavourings, colourants, fats, sugars and salts.

7. A process as claimed in claim 4, wherein the starting material is a product of the type used in the production of confectionery or chocolate selected from fruit extracts, sugars, maltodextrins, cocoa, coffee, chicory, malted cereals, milk and fats.

8. A process as claimed in claim 7, wherein the staring material contains one or more additives selected from flavourings, lecithins, boiled sugars, honey, caramel, nougatine, expanded cereals, drief fruit and candied fruit.

9. A process as claimed in claim 7 or 8, wherein the starting material contains cocoa, malted cereals, skimmed milk powder, butter oil, sucrose, lecithin, vanillin, mineral salts and vitamins.

10. A process as claimed in claim 7 or 8, wherein the article is cooled to a temperature below 25°C and coated in one or two stages with a chocolate-based coating.

11. A food product when obtained by a process as claimed in claim 1 or an obvious chemical equivalent thereof.

12. A food product when obtained by a process as claimed in claim 6 or an obvious chemical equivalent thereof.

13. A food product when obtained by a process as claimed in claim 7 or as obvious chemical equivalent thereof.