EP0198987B1 - Production unit for raw hydrated and treated cereals, especially rice - Google Patents

Abstract

1. Production unit adaptable for hydrated and conditioned raw cereals and rice in particular, characterized in that it consists essentially of three parts, namely the first sterilization part, the second conditionning part and the third cooling and packing part ; said first part comprising a horizontal type autoclave (2) with sliding doors (2a, 2b) equipped with rails (24a, 24b), emergent and interrupted at the doors, a storage silo (7) for the raw product (20), a roller carriage (23), a device for charging into and discharging from the autoclave the carriage processing the raw product, a humidifier (1) and a carriage raising device (13) ; said second part comprising a conditioning unit (5) together with its plastic sheet feeding device (15-19), its thermal conforming unit (22), its supply chute (16), its heatwelding station (18), a storage hopper (14) together with its metering device, a device (4) for charging into and discharging from the autoclave the carriage processing the sterile product, a system for wetting with hot sterile water (17) together with its generator (6) ; said third part comprising a cooling unit (8) evacuating the conditioned product (21), implementing the cooling law adapted to the product, together with a packing unit (9) ; first and second parts also being equipped with a hermetic chamber (11) in which a pressure booster (29) maintains an overpressure of sterile air by means of cartridges, all these elements being arranged and fitted out in such a way that the product is humidified and then biologically sterilized, and lastly hydrated for conditioning in the sterile state in hermetically sealed packing before undergoing controlled cooling, with the humidification and sterilization operations so arranged that the product is subjected to prior humidification to a maximum of 36 %, defining the critical gelling point, and with the hydration operation determined with sterile water so that the wetting water is fully absorbed on completion of hydration.

Description

The present invention relates to the field of cereals and applies to the particular case of cereals presented for consumption in the wet raw state.

Many methods of preparing cereals in the wet state have been well known for a very long time, in particular by appetization, in which the cooking and sterilization of the product are most often carried out moreover in conventional canneries.

All this is well known and does not relate to the invention.

This is characterized by a particular process of preparing grass cereals and rice in particular in the wet raw state and which makes it possible to reduce the cooking time.

This process has been described in French patent application _No. 82 20697 (2,537,404) of December 10, 1982 filed in the name of Doctor Albert CO-HEN.

According to this process, the preparation essentially consists in hydrolyzing the outer surface layer of the grains previously rendered sterile, then placing the sterile moist product thus obtained in sealed sterile packaging and then allowing hydration to continue in the packaging even without additional heating.

Such a preparation method which appeared new in itself, requires specific means of implementation.

Among these means, the present invention provides an adaptable production unit according to claim 1 which includes the direction of mobility.

It is known in fact that the conventional treatment of cereals such as the conventional parboiling of rice before it is dried, is carried out in production plants capable of very large quantities distributed to the places of consumption by appropriate means of transport. .

If such installations are perfectly suitable for cereals presented in the dry state, it is not the same in the case of the application of the present invention where the final product is offered in the wet raw state in packaging hermetically sealed.

The originality of such a process makes it possible to apply it from smaller units which are possibly mobile and therefore usable on many possible sites such as the rice mill for example or even the place of consumption which may be a city, a center or finally a storage place which can be a port or a warehouse or any other suitable place.

Although the constituent elements of the adaptable unit proposed in the present invention are not new in themselves, it will follow from the description below that their functional arrangement is particular and original and that it has never been previously proposed, to the knowledge of the applicant.

The invention will in any case be well understood in the remainder of the text which will give, in support of the appended drawings, a characteristic embodiment.

In the drawings:

• - Figure 1 shows, in a perspective view, the whole of the adaptable unit, according to one of the forms of the invention.
• FIG. 2 is a diagram defining the state of sterilization considered in the present invention,
• - Figure 3 is a diagram recalling the gelation conditions of starch.
• - Figure 4 is a functional diagram showing a complete cycle of treatment by the adaptable unit according to the invention.

Firstly, it should be specified that the so-called dry cereals, which do not have a humidity level generally greater than 15%, are the only ones which can be sterilized in the biological sense of the term before any subsequent treatment.

These cereals indeed contain an average water proportion of: wheat 13%, barley 14%, oats 13.3%, but 14%, rye 13.4% rice 12.5%, sorghum 13%, buckwheat 14% as well only 13% for other re-agglomerated products such as pasta for example.

The sterilization condition stems from numerous works by biologists, including those of:

• - AKERS M.J, KATHRYN M. KETRON and BR.THOMPSON (1982)
• - ANGELELOTTI R, J.H MARYANSKI, T.F BUT-LER, J.T PEELER, CAMPBELL (1968)
• - BALL C.O, (1928)
• - BENTEGAC (1982)
• - BRUCH, C.W (1974)
• - BYERS T (1982)
• - J.ECKBERG, W.FRIENBEN, IVR LEVINE (1978)
• - FOX.K and I.J PFLUG (1968)
• - L.GAIL, M.KLAVEHN (1982)
• - GAUTHIER C.A, SMITH G.M (1978)
• - R.HAJJAR and A.CUINE (1982)
• - R.HAJJAR, X.JAMET, A.CUINE and J.P.DUCLOS (1982)
• - NASA (1968)
• - PATASHNIK (1953)
• - PFLUG I.J (1973)
• - PFLUG I.J and RG HOLCOMB (1977)
• - PFLUG 1.J, SMITH G.M, SCHEYER M and P.A CHAPMAN (1976)
• - PHEIL C.G, PFLUG I.J, R.C NICHOLAS and J.A.L AUGUSTIN (1967)
• - J.H ROBERTSON, D.GLEASON and KIYOSHI TSUJI (1978)
• - L. TAGLIAPIETRA (1982)
• - TSUJI and S.J HARISSON (1978)
• - TSUJI and J.A BACH, J.H ROBERTSON and B.J BRUCE (1978)
• - J.VAN ASTEN and J.W DORPEMS (1982)
• - WARDLE M.D, W.A BREWER and M.L PETER-SON (1971)
• - WILKINSON R.L and R.A CAPUTO (1979)

According to the summary of the work of these authors, the sterilization condition is obtained strictly speaking only when the load to be sterilized has been exposed to a given temperature in saturated vapor pen during a perfectly determined minimum time. Thus, the duration of exposure of a polluted charge at 121.11 _° C. which is the so-called reference temperature in saturated steam and which results in a sterilizing effect such that the contamination of the charge is reduced by 90% or even that this contamination decreases by a power of 1 O, must be between 0.5 and 2 minutes.

This duration called "decimal reduction time" has been determined, in the pharmaceutical field which is the most rigorous, at 1 minute after having been established on BACILLUS STEREOTHERMOPHI-LUS which is the germ most resistant to humid heat.

The quality of sterilization of the cereals mentioned in the present application is at the level of these constraints or in other words, said treated cereals must be such that their contamination rate, which can be estimated at 10 ³ germs per unit initially under the usual conditions of storage, must be reduced by sterilization to less than 10-6 germs per unit where there is then a chance in a billion to meet a non-sterile unit in the load, this therefore bringing 103+ 10- ⁶ or 9 minutes at 121.11 _° C.

As an indication, the injectable pharmaceutical products have a lower rate of contamination 10- ⁹ germs per unit corresponding to 10-12 or 12 minutes at 121.11 ° C.

This is explained in Figure 2 where the curve defines in A the criteria; either sterilization (upper part-ST-.) Or simple decontamination (lower part-DE-.) Of a product exposed to saturated vapor in depending on temperatures and exposure times. After the sterilization considerations set out above and which imply an autoclaving method, the conditions for non-gelling of the starchy products thus treated must be examined.

It will be recalled in the thesis of VIRAKARTAKUSA-MA of Visconsin University (Dec. 1981), taking up previous work, that the humidity threshold allowing the total gelling of starch is about 36% and that below this threshold, complete gelation is impossible.

This is explained on the curves according to FIG. 3, from which some characteristic points of gelatinization at 36% for 50 _° C ( ₌ 185 ') - 60 _° C ( ₌ 65') - 70 _° C (= 15 ') can be seen and 90 _° C (= _{7 '} ).

It is therefore possible to autoclave a starchy product with a view to its subsequent hydration as soon as the accumulation of the initial humidity with the possible humidification provoked and the uptake of humidity resulting from autoclaving in wet vapor, does not exceed 36%.

It should be noted that any humidification caused prior to autoclaving has the effect of making the product more hydropexic, thereby facilitating subsequent hydration.

Returning to previous indications that it may be considered a disadvantage without sterilization quality reaching 10- ⁶ germs per unit submitting the charge for a period of about 12 minutes. in saturated steam for a product with a resulting humidity level of less than 36%.

• - une partie de stérilisation,
• - une partie de conditionnement,
• - une partie d'abaissement thermique et d'emballage.

To do this, the adaptable unit according to the invention is in the form of a rectangular container to transport standards and having essentially three parts:

• - a sterilization section,
• - a part of packaging,
• - a part of thermal reduction and packaging.

The sterilization part comprises, according to FIG. 1, an autoclave rep.2 of horizontal type with two doors, a humidifier of the load to be sterilized rep.1, an automatic charging mechanism rep.3, an automatic charging mechanism rep.4 and a supply silo rep.7 while a mechanism rep.13 ensures the elevation of a trolley rep.10 which will be discussed below.

According to this same figure, the packaging part includes an automatic packaging machine item 5, a hot sterile water generator item 6 and a buffer hopper 14 for weighing and dispensing the sterile product to the packaging unit.

The thermal lowering and packaging part essentially comprises a thermally controlled evacuation path 8 of the bagged product and a station 9 for packaging the bags. (not shown)

The assembly is completed by a flexible decontamination chamber 11 with slight overpressure of sterile air and it rests on the rigid base of the container 12 having, provided with its panels, a parallelepiped with an air-rail-road gauge. '' approximately: length B 5.90 m, width A 2.30 m and height C 2.20 m. An additional device constantly ensures sterility in the outlet chamber.

By following the production process of the product between its entry in the raw state 20 in the silo 7 and its exit in sterile packaging 21 in the thermal depressor 8, the following path can be followed.

Considering the application of the process to rice for example through a processing unit capable of 10 tonnes / day taken in the dry state, we start from silo 7 where a conventional distributor (not shown) has a given quantity of rice gross in the carriage 10 located in position 10a by the conventional lifting mechanism 13 (also not shown).

Immediately after this first operation, the load is moistened with potable water at room temperature using the device 1 and this under conditions and proportions determined by the nature of the original product (cargo rice, milled rice, parboiled. ....). The humidification could possibly be carried out upstream.

The carriage after humidification is raised to position 10b ready for charging into the autoclave 2 provided with two sliding doors alternately in the open or closed position.

The reason for this asynchronous operation is related to the sterile atmosphere to be kept inside the chamber 11 which is achieved by the fact that one of the two doors 2a or 2b is always closed by preventing communication of the sterile area with the outside.

The carriage is then brought into the autoclave 2 door 2b open, door 2a being closed, using of the charging mechanism 3 where, after closing the door 2b, the autoclaving sequence itself can take place.

This sequence includes automatic cycles controlled by microprocessor including the times of pre-filling, sterilization, cooling and decompression.

The remainder of the sequence then continues with a series of operations comprising opening the exit door 2a, the entry door 2b remaining closed, then using the de-charging device 4 the carriage is brought into position. 10 c or it is emptied of its sterile content into a buffer hopper 14, the arrangement of which enables the corridor 16 of the bagging machine 5 to be fed.

The rice taken out sterile from the autoclave is kept as it is by the chamber 11 which can be flexible by using plastic material in addition transparent sheets.

The bagging machine of which reference is made may be, not exclusively besides, of the conformation type of trays which means that in this case, a sheet 15 predisposed in a roll passes through a thermal shaper 22 which presents said trays formed in multirows in hallway 16.

The tray filling operation is carried out by metered and / or weighed distribution of rice from the hopper 14 using a known distributor (not shown).

The movement being continuous, the filled trays are then presented at the hydration station or a juicing system 17 delivers the quantity of sterile water required in each tray from the hot sterile water generator 6.

The end of the sequence is achieved by the operation of sealing the tray in a heat-sealing station 18 from a plastic sheet delivered by the roller 19.

The sterile product in a sealed tray 21 is finally taken up by a thermal step-down 8 which achieves the cooling law depending on the nature of the product treated

The trays 21 are then cartoned by a well known conventional machine 9. (not shown.)

It can therefore be seen that by application of the treatment resulting from the unit in accordance with the invention, the raw product 20 stored in the dry state will be packaged in the sterile raw hydrated state in ration doses ready to be delivered for consumption. , such as the trays 21 in the present example.

It has thus been possible to demonstrate that such ration doses could be tasted after cooking on the order of 3 to 4 minutes poured into a container after adding approximately 20 to 30% of cold water or even after approximately 1 minute as which in a microwave oven with packaging.

It should be noted that if the consumable product contained in the packaging 21 is completely sterile in the biological sense and if its conservation in an airtight packaging can thus be of very long duration equaling at least the duration of the usual food preserves (1), the original product can withstand significant pollution such as spore-like or molds of the toxin fungicide genus penicilium islandicum producers of luteoskyrin particularly developed on rice.

The three essential parts constituting the adaptable unit according to the invention and which comprise the sterilization part, the conditioning part and a thermal lowering and packaging part include particular elements whose operation will now be described in more detail. .

Thus the autoclaving phase of the product is located in 1 translation of a carriage 10 from a filling position to an unloading position.

This carriage, with an approximate capacity of 180 liters, must therefore be presented after vertical displacement in front of the opening of the autoclave 2, then must come out again to be presented above the hopper 14.

(1) Complies with the decree of February 10, 1955.

This is done thanks to the fact that said carriage is provided with rollers 23 engaging on two parallel rails 24a, 24b extending out of the autoclave on either side and which are broken in line with the doors.

The two charging and charging devices 3 and 4 of the carriage may be telescopic jacks provided at their ends with flexible pneumatic suction cups 25 and 26 adhering to the smooth wall of the carriage 10. Furthermore, the initiation of the setting cycles in movement of the cylinders and pressurization / depression of the suction cups is carried out automatically by programming.

The initial humidification is produced by a boom 1 for spraying drinking water, the quantity of which is regulated by solenoid valves. The final packaging part is conventional as is the metered distribution of product from the hopper 14.

Hydration takes place from distributors 17 controlled by solenoid valves and the hydration water is made sterile by a known filtration device and it is heated electrically, or by any other suitable means.

Finally, water 27 and electricity 28 arrivals are provided for the general supply of the assembly, just as an electric cartridge blower maintains a sterile air overpressure in chamber 11. (rep 29) and that 'a table (41) allows the control of the installation.

From a production point of view explained using the diagram according to FIG. 4, the adaptable assembly according to the invention proposes the treatment of 10 T / day of dried cereals.

It is therefore proposed to treat 10 T / d over 20 H or 0.5 T / H of product such as rice for example or 170 Kg of dry product every 20 Minutes corresponding to the three cycles per hour provided by the unit according to the invention.

The load is placed in the carriage 10 at the instant of rep 30 and after a determined time, it therefore has a given induced humidification. It should be noted that approximately 15% of water is already contained (rep 33) in the product commercially considered dry. Humidification can possibly be carried out upstream in the silo for example full.

The sterilization phase proper can be carried out for approximately 13 minutes (rep 34) which gives, with reference to the diagram according to FIG. 2 and for a temperature of 123 _° C. for example in saturated steam, a characteristic point (rep 40 ) located above the sterilization reference curve.

The sterile product is then discharged into the storage hopper (rep 35) from where it is dosed and conditioned but not yet hydrated. This hydration is carried out dose by dose (rep 37) by letting it continue (rep 38) after the packaging has been sealed.

At the same time and as soon as the unloading of the trolley has been completed (rep 36), it returns (rep 39) to the initial loading point (rep 30) by crossing the autoclave again while one of the two doors remaining closed, protects the assembly from any external pollution.

The conditioned doses undergo a thermal reduction, the duration of which is adjusted as a function of the product treated, this duration not being included in the treatment cycle since it takes place after packaging (rep 42) possibly at the level of the wrapper rep. 9 in the boxes themselves.

Using the production figures mentioned for rice previously, it may be indicated that the treatment of 170 kg of rice taken in the dry commercial state gives, per 20-minute cycle and after humidification, sterilization and hydration, an amount of approximately 1,200 Kg. Per hour, that is to say another 24,000 Kg / day in 20 hours of operation, or approximately 100,000 ration doses of 240 Grams each in operating minimum.

It is specified that the water of hydration must be absorbed during the thermal reduction.

The unit which is presently mentioned may possibly be divided into sub-units reconstituted in situ for reasons notably of congestion, for example linked to transport. In the same spirit, a planned increase in production capacity could also lead to split the constituent parts so that the unit would then only contain a single part which could be that of sterilization for example. In the latter case, known means for transferring the product such as by sterile sealed conduit for example, could link the parts together.

The present description has been given only to clearly show how the invention can be implemented and it is obvious in this respect that all the adaptations or modifications which would be made in its spirit would remain within its framework which is defined in the claims that follow.

Thus, the invention applies even if the charging and discharging systems are of a different design, that the packaging machine is of a different nature for producing sachets bags or other containers instead of trays or that the the autoclave is optionally of the vertical type with suitable load transfer, from the moment the product emerges from the treatment in the sterile hydrated raw state in its hermetic packaging.

Finally the sterile exit airlock (43) of the chamber (11) can be formed by passing the hermetically sealed sachets through an appropriate sterile solution or a protected area by sterile, UV or other radiation so that the sterility of the chamber is ensured even in the event of temporary unit shutdown, for example.

Claims (12)

1. Production unit adaptable for hydrated and conditioned raw cereals and rice in particular, characterized in that it consists essentially of three parts, namely the first sterilization part, the second conditioning part and the third cooling and packing part; said first part comprising a horizontal type autoclave (2) with sliding doors (2a, 2b) equipped with rails (24a, 24b), emergent and interrupted at the doors, a storage silo (7) for the raw product (20), a roller carriage (23), a device for charging into and discharging from the autoclave the carriage processing the raw product, a humidifier (1) and a carriage raising device (13); said second part comprising a conditioning unit (5) together with its plastic sheet feeding device (15-19), its thermal conforming unit (22), its supply chute (16), its heatweld- ing station (18), a storage hopper (14) together with its metering device, a device (4) for charging into and discharging from the autoclave the carriage processing the sterile product, a system for wetting with hot sterile water (17) together with its generator (6); said third part comprising a cooling unit (8) evacuating the conditioned product (21), implementing the cooling law adapted to the product, together with a packing unit (9); first and second parts also being equipped with a hermetic chamber (11) in which a pressure booster (29) maintains an overpressure of sterile air by means of cartridges, all these elements being arranged and fitted out in such a way that the product is humidified and then biologically sterilized, and lastly hydrated for conditioning in the sterile state in hermetically sealed packing before undergoing controlled cooling, with the humidification and sterilization operations so arranged that the product is subjected to prior humidification to a maximum of 36%, defining the critical gelling point, and with the hydration operation determined with sterile water so that the wetting water is fully absorbed on completion of hydration.

2. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that the sterilization part gives rise to socalled "biological" sterilization quality of the product to be processed, whereby the level of contamination lies below the sterilization-decontamination curve (A) in application of the "decimal reduction ratio".

3. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claims 1 and 2, characterized in that the unit is constructed in compliance with the gauge (12) of standard containers.

4. Adaptable production unit for hydrated and conditioned raw cerelas and in particular rice, in accordance with claim 1, characterized in that the device for charging into and discharging from the autoclave the carriage processing the raw product is a telescopic cylinder (3) carrying a flexible suction device (26) operating by pressure reduction.

5. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that the device for charging into and discharging from the autoclave the carriage processing the sterile product is a telescopic cylinder (4) carrying a flexible suction device (25) operating by pressure reduction.

6. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that the wetting system (17) determines the quantity of sterile water to be delivered by automatically actuated solenoid valves.

7. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that it can be broken down into sub-units reformed in-situ.

8. Adaptable production unit for hydrated and conditioned raw cerelas and in particular rice, in accordance with claim 1, characterized in that it may comprise only one constituent part or appropriate means for transferring the product in its then- present form via a hermetic sterile conduit joining together each of the parts, thus reforming said unit.

9. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claims 1 to 8, characterized in that all the charging, humidifying, sterilizing, charge transfer, weighing-metering, packing and cooling together with packaging take place automatically, controlled and coordinated from a control panel (41) made available to the operator.

10. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in acordance with claim 1, characterized in that the conditioning unit (5) with its plastic sheet feeding devices (15-19) bring about sterile hermetic packing containing the hydrated crude sterile product, allowing subsequent accelerated cooking of the product contained.

11. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that chamber (11) is fitted with an exit lock (43) of the products packed and can be protected by sterile gas or by ultra-violet radiation by passing said product through a sterile solution or protected zone.

12. Adaptable production unit for hydrated and conditioned raw cereals and in particular rice, in accordance with claim 1, characterized in that cooling can be brought about at the packing unit (9), for instance in the boxes themselves.

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