The present invention concerns a plant and a method for heat treatment of food products and the like.

More specifically, the invention concerns a plant and a method for realizing an optimum cooking or enzymatic inactivation of vegetables.

At present, single block plants are employed to carry out said cooking or enzymatic inactivation treatments, said plants being divided into sections that will be indicated as stages. Number of stages is mainly due to operating economy.

The higher is the number of stages, the lower are vapour and heating water consumption.

In said known plants divided into a plurality of stages, product to be subjected to the treatment is advanced through a pre-heating stage, then through a cooking or enzymatic inactivation stage, to pass then through a cooling stage, to be then discharge from the plant.

In said plants, product is heated by a heating fluid flowing counter current with respect to the same product to be subjected to treatment.

Usually, treatment fluid is softened and demineralised, drinkable water, supplied counter current with respect to the product.

More specifically, in this first kind of known plants, substantially cold water enters, counter current, within the plant, passes through communicating vessels through all the stages, wherein, first subtracts heat from product into the cooling stage, where it is heated up to 70°C.

Now, water passes to the cooking or enzymatic inactivation stage, within which it maintains a constant enzymatic inactivation level, occurring at about 95°C.

Then , water reaches pre-heating stage within which, always counter current, heats product at about 65°C and then exhausted its function, exit from a plant discharge.

Thus, following the path of the product to be subjected to treatment, the same is first p re-heated, i.e. gradually heated, in about 1 minute, from room temperature to the temperature of about 65°C, then it is supplied within the cooking or enzymatic inactivation stage, wherein it is heated at about 95°C, then product is cooled within cooling stages wherein it yields heat to water counter current passing through the plant, heating the same, as described in the above.

Nowadays an always more high pressure exists to simplify plants, particularly reducing their dimensions and increasing their efficiency.

Thus, main problem to be solved by the present invention is that of realising a plant structurally simpler than traditional plants described in the above, ensuring at the same time at least the same efficiency and productivity.

Main object of the present invention is that of realising a plant for thermal treatment of food products and like solving the above problem and that is structurally simpler than known plants described in the above and ensuring at least the same efficiency of known plants.

In view of the above, it is an object of the present invention that of suggesting a plant for thermal treatment of food products permitting obtaining a higher productivity with respect to the above known plants.

Another object of the present invention is that of realising a method for thermal treatment of food products and like that is simpler than methods actuated in above traditional plants.

Still another object of the present invention is that of suggesting a method for thermal treatment of food products permitting obtaining a higher productivity with respect to methods actuated in above traditional plants.

These and other objects, that will be much more clear in the following, are obtained by a plant and a method for thermal treatment of food products and like, according to the relevant independent claims.

Detailed features of the plant and of the method for thermal treatment of food products and like according to the invention are described in dependent claims.

Further features and advantages of the invention will be much more clear from the description of the two preferred, but not limitative, embodiments of the plant and method for thermal treatment of food products and like according to the invention, shown, for illustrative but not limitative purposes in the enclosed drawings, wherein:

figure 1 shows a schematic view of a first embodiment of the system according to the invention suitable to realise the inventive method; figure 2 shows a schematic view of a second embodiment of the system according to the invention suitable to realise the inventive method.

Making reference to the enclosed figures, a plant for heat treatment of food products and like is generically indicated by reference number 10.

Said plant 10 is particularly suitable to cook and/or enzymatic inactivate food products such as vegetables, e.g. leafy vegetables, tubers, fruit, or food products like meat, cheese, or sausages.

According to the present invention, plant 10 has a specific peculiarity comprising at least a thermal treatment stage 11 , for cooking or enzymatically treating the product, suitable to quickly heat food products 12 at the treatment temperature.

Thus, it is prevented the needing of a pre-heating stage provided in known thermal treatment plants, thus permitting realising a plant according to the invention structurally simpler than known plants, and that, with respect to the latters, has a higher productivity since it provides a lower treatment time, being it saved time dedicated in known plants to preheating.

According to the present invention, said thermal treatment stage 11 comprises a treatment duct 14 for food products 12, feeding means 15, for cold mixing said food products 12 with said liquid 13, and heating means 16, for heating said liquid 13, to provide a heat treatment of said food products 12.

A stream of liquid 13, mixed with said food products 12 flows within said treatment duct 14 so that the latter, receiving heat at least from said liquid 13, are thermally subjected to treatment, thus obtaining cooking or enzymatic inactivation.

Feeding means 15 are hydraulically connected to said treatment duct 14, for mixing cold food products 12 with said liquid 13, and introducing the same within the treatment duct 14.

By the term "cold" it is meant that said food products are substantially at room temperature.

Heating means 16 are suitable to heat the above liquid 13 to obtain a thermal treatment of food products 12 to the treatment temperature, suitable for cooking or for the enzymatic inactivation of the same food products 12. Preferably, said treatment temperature is substantially higher than 90 ° C, and advantageously within the range between 92°C and 98°C.

Further, according to a first embodiment of the invention, shown in figure 1 , said heating means 16 preferably comprise an external jacket 17, outside the treatment duct 14, defining, externally to the latter, a first cavity 18 for the passage of a heating fluid suitable to transmit heat, through the walls of said treatment duct 14, to said liquid 13 and to said food products 12 dispersed therein.

Always according to the first embodiment, said heating means

16 are suitable for forcing said heating fluid in said cavity 18 in a counter current direction A with respect to the flowing direction B of said liquid 13 in said treatment duct 14.

More specifically, said heating means 16 comprise a hydraulic circuit 19, hydraulically connected to a reservoir or feeder 20 of said heating fluid and comprising at least one heat exchanger 21 , for heating said heating fluid.

Heating exchanger 21 is suitable to heat heating fluid. Said feeding device 22, preferably comprised of at least a hydraulic pump in case heating fluid is a liquidl 3, is hydraulically connected to said heat exchanger 21 and to said cavity 18 for moving said heating fluid from said heat exchanger 21 to said cavity 18, according to said counter current direction A.

According to the second embodiment of the invention, shown in figure 2, heating means 16 comprise a heating device 23, e.g. comprised of a thermal exchanger or of a boiler, hydraulically connected upstream to said supply means 15 and suitable for heating said liquid 13 which is directed to enter into said treatment duct 14.

On the basis of the specific needing of the present invention, a plant according to the invention can be realised according to the first or to the second embodiment described in the above, or it can be comprised of the combination of said embodiments, in this case being advantageously provided both with the outer jacket 17, and preferably also with hydraulic circuit 19, and with said heating device 23.

Further, the plant according to the invention preferably also comprises a liquid 13 recovery device 24, hydraulically coupled downward the treatment duct 14 and upward the heating device 23, for recovering the liquid 13 from treatment duct 14 and to and hydraulically feed it to said heating device 23.

Said heat treatment stage 11 advantageously comprises extraction means 25 hydraulically connected downstream to said treatment duct 14 for extracting said products food 12 subjected to process, from said liquid 13.

More specifically, preferably recovery device 24 comprises a collection tank for collecting liquid 13 and food products 12, and extraction means 25 comprise a drain conveyor belt, partially submerged within said tank and suitable to extract from the latter only food products 12, draining water.

Further, plant 10 preferably comprises at least a cooling stage 26 for food products 12 discharged from treatment duct 14, downward the thermal treatment stage 11.

It is further object of the present invention, a method for heat treatment of food products 12 and the like, suitable to be implemented in a plant 10, comprising the following steps:

- mixing food products 12 in a cold transport and/or treatment liquid 13, preferably water;

- heating said food products 12 mixed in said liquid 13, and

- maintaining, during a set treatment period, said food products 12 at a treatment temperature, preferably within the range between 92°C and 98 ^C C, for their cooking or for their enzymatic inactivation.

According to the present invention, said method has a specific feature in that heating of said food products 12 to said treatment temperature is quick and comprises at least one of the following steps:

- heating, substantially to said treatment temperature, said liquid 13, prior to said step of mixing said food products 12 with said cold liquid 13; and/or

- heating said liquid 13 and said food products 12, after said step of mixing said food products 12 with said liquid 13, by heat exchange with a heating fluid having a temperature at least equal to said treatment temperature.

Preferably, said heating fluid is water vapour or a liquid, e.g. water. The described invention can be subjected to many modifications and variations, all included within the scope of the enclosed claims.

Further, all details can be replaced by other elements which are technically equivalent.

Substantially, materials employed, as well as shape and dimension, can be modified on the basis of the specific needing and of the specific technique.

In case constructive and technical features indicated in the following claims by signs or reference numbers, said signs or reference numbers have been indicated only to give a better understanding of the same claims and consequently they are not a limitation when interpreting each element indicated, only for illustrative purposes, by said signs or reference numbers.