WO2003068663A1

WO2003068663A1 - Procedure and equipment for filling containers with aseptic liquid

Info

Publication number: WO2003068663A1
Application number: PCT/HU2003/000012
Authority: WO
Inventors: Frigyes RÉGER
Original assignee: Lamba Kft.
Priority date: 2002-02-11
Filing date: 2003-02-10
Publication date: 2003-08-21
Also published as: HU0200491D0; AU2003205918A1; HUP0200491A2

Abstract

In a procedure for the filling of storage vessels with aseptic liquid, the storage units are sterilised with a disinfectant in a washing-sterilising unit, then the storage vessels are taken to a pressurised, aseptic space where the disinfectant is removed and the storage vessels are rinsed, then they are taken into a pressurised, aseptic chamber at a temperature of at least 70 °C, the aseptic space is maintained in the chamber by the injection of sterile air at a temperature of at least 70 °C, then the storage vessels are filled with the aseptic liquid and are sealed with sterilised sealing elements or by welding. Between the washing-sterilising unit (2) and the filling-sealing chamber (6) there is an emptying-rinsing unit (4), connected to the washing-sterilising unit (2) and the filling-sealing chamber (6) via inverter chambers (3), the filling-sealing chamber is pressurised with sterile air at a temperature of at least 70 °C, and the storage vessels in the washing-sterilising unit (2) and in the emptying-rinsing unit (4) are moved always linearly, in one line.

Description

PROCEDURE AND EQUIPMENT FOR FILLING CONTAINERS WITH ASEPTIC IQUID

The subject of the invention relates to a procedure for the aseptic filling of storage vessels and to equipment for the realisation of the procedure. The procedure according to the invention can be used efficiently for the long-term, sterile storage of liquid foodstuffs and luxury goods. The procedure and equipment according to our invention can be used to especially great advantage for the aseptic filling and long-term storage of still, this is carbon dioxide-free drinks, like, for example, fruit juices, fruit nectars, other drinks with fruit content, soft drinks, milk and still mineral waters.

The requirement for the aseptic filling of storage vessels in the food industry has been known of for a long time. Numerous procedures have been worked out in the interest of the realisation of sterile filling and storage, so that the drinks can be kept for an extended period of time.

According to a known procedure a preserving agent is added to the drink, with which its shelf life is significantly increased. The disadvantage of this procedure is that it is not suitable for the production of drinks with a high fruit content. Another disadvantage is that preserving agents are not acceptable to everyone, and there are even people for whom they cause allergic reactions. According to another known procedure the drinks are heated before filling and are placed into the vessels while hot, in this way sterilising the liquid. In this procedure in the case of the very frequently used thermoplastic bottles the hot liquid has to be prevented from softening the bottles. Such a solution is presented in patent number CH 403 605, where the hot liquid is filling into PET (polyethylene terephthalate) bottles. In order to prevent the deformation of the plastic bottle, which softens at approx. 65 °C, the empty bottles are placed in a cold liquid before filling. The sterilised, hot liquid is filled into the bottle in a few seconds. As the temperature of the material of the bottle increases by 1 °C per minute, it does not have enough time to reach the high temperature and soften. This procedure is relatively fast and simple, its disadvantage, however, is that not every drink an extended period of high temperature without damage to its enjoyment value. Another disadvantage of this procedure is that not all storage vessels can be filled with hot liquid.

PET bottles with a high degree of heat resistance (about 100 °C) also exist, but the price of these is twice that of normal PET bottles.

According to another, known method of aseptic filling and storage the liquid is first sterilised and the cooled, sterilised liquid is filling into the pre-sterilised storage vessel, and this is sealed with a cap that has also been pre-sterilised. According to a known solution the sterilisation of the storage vessel, the filling of the sterilised liquid as well as the sealing of the storage vessel is carried out in an aseptic space. According to the known solutions the bottle steriliser, the filling and sealing equipment are placed in the same room, where the aseptic conditions are attained with the multiple filtering of the air introduced into the room. The disadvantage of this solution is that the filtering and purification of the large amount of air is very expensive. A further disadvantage is that in the case of a breakdown, if it is required for someone to enter the filling area creating aseptic conditions again requires a long period of time.

Patent description DE 196 42 987 set as its aim to reduce the aseptic space and with this to realise a more economic filling procedure, which procedure and equipment also relates to the sterilisation and filling of the storage vessels. According to the invention presented here the sterilisation, filling and sealing of the storage vessels containing liquid foodstuffs is carried out without creating an aseptic space. The storage vessels are transported on a continuous, linear conveyor belt to workstations following one another, where the storage vessels are preheated, sterilised, dried, filled and sealed. According to the invention the set aim is reached by spraying a jet of sterilising medium under pressure into every single storage vessel for the sterilisation through the vessel's opening in such a way so that on reaching the base of the vessel it turns back, exits through the opening of the vessel and a part of it is sucked up. The sterilisation of the bottles is carried out with hydrogen peroxide and the preheating and drying with hot air. The disadvantage of the invention is the complex construction and costly set up as well as it not being able to carry out sterile filling and sealing reliably. The aim of the invention with the further development of the state of the art is to work out a procedure and equipment with the help of which liquid foodstuffs can be filled into storage vessels reliably in sterile conditions, using simple equipment, cheaply.

Our invention is based on the recognition that if the sterilisation, filling and sealing of the storage vessels is carried out in a sterile space that is only just surrounded by the machine units, and in which the aseptic environment is created and maintained by the blowing in of pressurised, sterile, hot air, then the long shelf life of liquid foodstuffs can be efficiently solved using simple equipment. Furthermore, our invention is also based on the recognition that the PET bottles can withstand a short period of time in an airspace at between 85-95 °C without damage. If in a part of the aseptic space the hot, sterile air is cooled with a cold, rinsing liquid, and in the filling part the bottles are filling with cold, aseptic liquid, then the PET bottles will withstand the short-term high temperature with safety, without suffering damage.

The invention, then, relates to a procedure for the filling of storage vessels with aseptic liquid, during which the storage vessels are sterilised, filled with aseptic liquid and sealed with sterilised sealing elements. The essence of the invention is that the storage units are sterilised with a disinfectant in the washing- sterilising unit, then the storage vessels are taken to the pressurised, aseptic space where the disinfectant is removed and the storage vessels are rinsed, then they are taken into a pressurised, aseptic chamber at a temperature of at least 70 °C, the aseptic space is maintained in the chamber by the injection of sterile air at a temperature of at least 70 °C, then the storage vessels are filled with the aseptic liquid and are sealed with sterilised sealing elements or by welding. According to an advantageous method of realisation of the procedure the storage vessels are disinfected with hydrogen peroxide.

According to a further advantageous method the storage vessels are rinsed with sterile liquid and/or pressurised sterile air, advantageously at a pressure of 0.33 bar.

Furthermore, it is also advantageous if in the procedure we use a plastic, glass or metal bottle as the storage vessel, in a given case we can use a PET bottle or a single or multi-layered film bag. We use pasteurised liquid that has been cooled back down to a maximum of 55 °C as the aseptic liquid.

As the aseptic liquid we put still drinks, fruit juice, fruit nectar, other drinks with fruit content, soft drinks, milk, other milk products or water into the storage vessel.

The subject of the invention also relates to equipment for the realisation of the procedure, which has a storage vessel washing-sterilising unit, and furthermore, a filling-sealing chamber that contains the filling unit that fills the aseptic liquid and the sealing unit that seals the storage vessels. The essence of the invention is that between the washing-sterilising unit and the filling-sealing chamber there is an emptying-rinsing unit, the emptying-rinsing unit is connected to the washing-sterilising unit and the filling-sealing chamber via inverter chambers, the filling-sealing chamber is pressurised with sterile air at a temperature of at least 70 °C and maintained at at least 70 °C, and the inverter chamber, the emptying-rinsing unit and the other inverter chamber are arranged and connected to the filling-sealing chamber so that the pressurised, sterile air put into the filling-sealing chamber flows over the storage vessels and fills their airspaces, furthermore, the storage vessels in the washing-sterilising unit and in the emptying-rinsing unit are moved always linearly, in one line.

According to an advantageous construction of the equipment in the washing- sterilising unit it has a conveyer belt moving the storage vessels linearly and arranging them in line, furthermore, it has a slot filler that injects the disinfectant into the storage vessels.

According to a further advantageous arrangement the inverter chamber has an arced guide element that inverts the storage vessels individually by 180°.

Another advantageous set-up is when the emptying-rinsing unit is arranged to drip the disinfectant out of the storage vessels and has an opening for the injection of rinsing material.

Henceforward we will present the invention in more detail on the basis of a drawing, where

Figure 1 shows the theoretical arrangement of the equipment according to the invention. With the procedure according to the invention liquid foodstuffs or luxury goods can be filling in storage vessels in sterile conditions. The storage vessel filled according to the invention is especially suitable for the long-term storage of fruit juices, fruit nectars, other drinks with fruit content, soft drinks, milk and milk products or water without the use of preservatives.

During the procedure the liquid foodstuff is sterilised separately, outside of the equipment. This sterilisation may take place through pasteurisation and the re- cooling of the liquid or via another method, for example UV treatment. The sterilised liquid is injected in a sterile pipe into the filling-sealing chamber 6 of the equipment, in which we establish an aseptic space. It is not necessary for the temperature of the sterilised liquid to be high in order for it to be filled into the storage vessel in a sterile manner, so the liquid does not lose any of its taste or enjoyment value. The liquid to be filled can be at room temperature, but the procedure is not influenced, the liquid is not damaged and the degree of efficiency of the procedure is improved if the temperature of the liquid is higher, 55 °C at the most. In the filling-sealing chamber we establish a hot, aseptic, pressurised space. As a temperature above 70 °C is generally enough for sterilisation, a sterile environment can be created by injecting air at a temperature over 70 °C. We prevent air that has not been sterilised from getting into the aseptic space by pressurising it. Even a quite small overpressure, 0.03 bar for example, is sufficient for air to flow only out from the aseptic chamber and for the sterile conditions to be maintained. The airflow direction 5 of the pressurised, sterile air is marked on the drawing with a dashed line.

The airspace of the filling-sealing chamber 6 is in common with the airspace of the inverter chambers 3 and the emptying-rinsing unit 4. An aseptic environment is also ensured in these spaces, which is maintained with the injection of pressurised, sterile air flowing out of the filling-sealing chamber 6. The at least 70 °C air injected into the filling-sealing chamber 6 loses some of its temperature in the connected spaces. This temperature loss does not result in a reduction of sterility in the connected spaces, as the overpressure there prevents non-sterile air getting into the aseptic space. At the same time the cooling of the air in the inverter chambers 3 and in the emptying-rinsing unit 4 involves the advantage that in these spaces the bottles do not get overheated, which is useful especially in the case of the filling of PET bottles.

After filling the aseptic liquid in the filling-sealing chamber 6 the storage vessel is sealed by welding or with a plastic or metal sealing element that provides an airtight seal. The sealing elements may be sterilised within the aseptic space with hot air, but they may also be sterilised outside the aseptic space with disinfectant, or a combination of the two sterilisation solutions may also be used.

The equipment according to the invention is constructed of elements that are known in themselves, therefore we will not provide details of their structural form. As it can be seen on figure 1 the equipment consists of a washing-sterilising unit 2, an inverter chamber 3, an emptying-rinsing unit 4 positioned one after the other, as well as an inverter chamber 3 and a filling-sealing chamber 6 connected to this. The hot air maintaining the aseptic space is injected into the filling-sealing chamber 6 and flows through the space according to the airflow direction 5.

The storage vessels to be filled are introduced into the equipment according to the direction of travel of the storage vessels 1. Any glass, metal or plastic bottle may be used as a storage vessel or even a single or multi-layered film bag may be used. Of the plastic bottles both non-thermoplastic and thermoplastic bottles, for example PET bottles, are suitable for the aseptic filling according to the invention. The storage vessels are taken into the washing-sterilising unit 2 on a linear conveyor belt, where the storage vessels travel under a slot filler, through which the disinfectant continuously flows, washing the storage vessel both on the outside and the inside. At the end of the washing-sterilising unit 2 a conveyor screw not shown on the drawing individually transfers the storage vessels to the aseptic inverter chamber 3. The disinfectant adhered to the wall of the storage vessel prevents the storage vessel from becoming infected before it is placed in the sterile space.

The inverter chamber 3 contains an arced guide element that inverts the storage vessels individually by 180° so that they enter the emptying-rinsing unit 4 with their openings pointing downwards. In the first section of the emptying-rinsing unit 4 the disinfectant is dripped out of and off the storage vessels, then in the second section the storage vessels are continuously rinsed inside and out with a sterile, cold liquid, which is advantageously water. With this cold water rinse we do not only attain storage vessels that are completely disinfectant-free, but also that the hot air flowing out of the aseptic space and, as a consequence, the storage vessels are cooled down. So during the use of PET bottles, the bottles are not heated up so much and their softening can be more reliably avoided. Naturally other materials can be used as a rinsing agent, for example hot air, or a combination of water and air can be used.

At the end of the emptying-rinsing unit 4 the storage vessels are taken by a conveyor screw, not shown on the drawing, into the inverter chamber, where there is a guide element that inverts the storage vessels by 180°. On entering the filling- sealing chamber 6 the now upright storage vessels are first filled with aseptic liquid in the filling unit 7, then in the sealing unit they are sealed with an airtight seal. The filled, sealed storage vessels come out of the filling-sealing chamber 6 according to the direction of travel of the storage vessels 1 and progress to the labeller unit not shown on the drawing.

The hot air that maintains the aseptic space flows in the space in accordance with the direction or movement of the air 5.

From the point of view of the realisation of the invention it is especially important that the storage vessels progress in the washing-sterilising unit 2 and the emptying-rinsing unit 4 always linearly, in single file, and that they enter the inverter chamber one by one. By implementing this measure they dimensions of the aseptic space can be significantly reduced. It is sufficient to make the aseptic spaces just large enough to enclose the washing, disinfecting and filling production lines. The establishment and maintenance of the small, sterile spaces involves significant cost reductions as compared to the known solutions.

Example 1

We filled PET bottles with soft drink using the procedure and equipment according to the invention. In the equipment the length of the washing-sterilising unit 2, the inverter chambers 3 and the emptying-rinsing unit was set at 10 m. The cross section of the emptying-rinsing unit 4 was set at 0.4x0.6 m, which size was suitable for the hot, sterile air to continuously and linearly thoroughly rinse through the aseptic space. By injecting hot, sterile air at 95 °C into the filling-sealing chamber 6 we set the temperature of the aseptic space so that it was between 85-90 °C, furthermore we maintained 0.03 bar of overpressure in the aseptic space.

In the emptying-rinsing unit 4 we rinsed the bottles with cold, sterile water at 14

°C. In the filling unit 7 we filled the bottles with pasteurised, heat treated, sterile soft drink that has been cooled down to 23 °C.

In this set-up the capacity of the equipment was 8000 bottles/hour.

Example 2

In the equipment presented in example 1 we filled mineral water. By injecting air at 300 °C into the filling-sealing chamber 6 we maintained a chamber temperature of 180-200 °C, furthermore we also maintained an overpressure of 0.04 bar. The other parameters of the procedure are the same as those given in example 1. The capacity of the equipment was 7500 bottles/hour.

List of references

1. Direction of travel of the storage vessels

2. Washing-sterilising unit

3. Inverter chamber

4. Emptying-rinsing unit

5. Airflow direction

6. Filling-sealing chamber

7. Filling unit

8. Sealing unit

Claims

1. A procedure for the filling of storage vessels with aseptic liquid, during which the storage vessels are sterilised, filled with aseptic liquid and sealed with sterilised sealing elements, characterised by that the storage units are sterilised with a disinfectant in the washing-sterilising unit, then the storage vessels are taken to the pressurised, aseptic space where the disinfectant is removed and the storage vessels are rinsed, then they are taken into a pressurised, aseptic chamber at a temperature of at least 70 °C, the aseptic space is maintained in the chamber by the injection of sterile air at a temperature of at least 70 °C, then the storage vessels are filled with the aseptic liquid and are sealed with sterilised sealing elements or by welding.

2. The procedure according to claim 1 characterised by that the storage vessels are disinfected with hydrogen peroxide.

3. The procedure according to claim 1 or 2 characterised by that the storage vessels are rinsed with sterile liquid and/or pressurised sterile air, advantageously at a pressure of 0.33 bar.

4. The procedure according to any of claims 1-3 characterised by that we use a plastic, glass or metal bottle as the storage vessel, or a single or multi- layered film bag.

5. The procedure according to claim 4 characterised by that a PET bottle is used as the storage vessel.

6. The procedure according to any of claims 1-5 characterised by that we use pasteurised liquid that has been cooled back down to a maximum of 55 °C as the aseptic liquid.

7. The procedure according to claim 6 characterised by that as the aseptic liquid a still drink is filled into the storage vessels.

8. The procedure according to claim 7 characterised by that as the still drink we put fruit juice, fruit nectar, other drinks with fruit content, soft drinks, milk, other milk products or water into the storage vessels.

9. Equipment for the realisation of the procedure according to^" clarmV (3 whjcb. has a storage vessel washing-sterilising unit, and furthermore, a filling- sealing chamber that contains the filling unit that fills the aseptic liquid and the sealing unit that seals the storage vessels characterised by that between the washing-sterilising unit (2) and the filling-sealing chamber (6) there is an emptying-rinsing unit (4), the emptying-rinsing unit (4) is connected to the washing-sterilising unit (2) and the filling-sealing chamber (6) via inverter chambers (3), the filling-sealing chamber is pressurised with sterile air at a temperature of at least 70 °C and maintained at at least 70 °C, and the inverter chamber (3), the emptying-rinsing unit (4) and the other inverter chamber (3) are arranged and connected to the filling-sealing chamber (6) so that the pressurised, sterile air put into the filling-sealing chamber (6) flows over the storage vessels and fills their airspaces, furthermore, the storage vessels in the washing-sterilising unit and in the emptying-rinsing unit (4) are moved always linearly, in one line.

10. The equipment according to claim 9 characterised by that in the washing- sterilising unit (2) it has a conveyer belt moving the storage vessels linearly and arranging them in line, furthermore, it has a slot filler that injects the disinfectant into the storage vessels.

11. The equipment according to claim 9 or 10 characterised by that the inverter chamber (3) has an arced guide element that inverts the storage vessels individually by 180°.

12. The equipment according to any of claims 9-11 characterised by that the emptying-rinsing unit (4) is arranged to drip the disinfectant out of the storage vessels and has an opening for the injection of rinsing material.