The present invention relates to a method and a plant for extracting juice or puree from a food product.

Currently, the extraction of juice or puree from a food product comprises numerous phases and in particular: - trituration of the product; - possible pre-refinement with sieves with large holes, typically having diameter of 2-4 mm, to eliminate seeds, peels and petioles); enzymatic deactivation by heating the triturated product; - final heat refinement, passing the triturated product through sieves with holes of smaller diameter, typically 0.5 mm, to obtain the juice or puree; - deaeration of the product; - sterilisation of the product with additional heating thereof.

However, it is desirable to work the product without heating as much as possible, avoiding heat stresses, and it is also desirable to reduce the phases of the method as well as its duration.

DISCLOSURE OF INVENTION.

The aim of the present invention therefore is to eliminate the aforesaid drawbacks making available a simplified method and plant that allow the ultra-rapid extraction of juice or puree without heating.

Said aims are fully achieved by the method and the plant of the present invention, characterised by the contents of the claims set out below.

In particular, the method comprises the following phases: - cutting the product into slices under vacuum, with the slices remaining in the environment under vacuum for a sufficient time to allow their adequate deaeration; - cold extraction of the juice or puree by means of a known strainer/refiner; - sterilisation of the juice or puree by integrated enzymatic deactivation.

Before the cold extraction of the juice or puree, a dynamic mixing of the slices can be provided, providing a homogeneous consistency to the pulp.

The plant comprises, inside the deaerator and in an environment under vacuum, a device for cutting the product into slices. Said slices are then fed to a known refiner/strainer wherefrom exits juice or puree, which then passes into a steriliser with integrated enzymatic deactivation.

The deaerator, wherein is inserted a device for cutting the product into slices, preferably comprises a baffle, for instance of the conical type, so shaped as to maintain for a certain time, preferably about 90 seconds, the slices in the deaerator under vacuum before they are fed by gravity to a feeding pump.

Between the deaerator and the refiner/strainer can be present a dynamic mixer which receives the slices and is so shaped as to provide the pulp with homogeneity of consistency. The dynamic mixer preferably comprises a rotor with hexagonal cross section, rotating with adjustable speed inside a stator with substantially square cross section.

BRIEF DESCRIPTION OF DRAWINGS.

This and other characteristics shall become more readily apparent from the following description of a preferred embodiment illustrated, purely by way

of non limiting example, in the accompanying drawing tables, in which: -Figure 1 shows a global diagram of the plant and of the method; - Figure 2 shows a cross section of a component of the plant.

BEST MODE FOR CARRYING OUT THE INVENTION.

With reference to the figures, the reference number 1 indicates a deaerator that receives the product from a substantially known discharge valve 2 (for instance star shaped) actuated by a motorisation 3.

The product, typically fruit or whole vegetables, enters the deaerator 1 which is under vacuum because it is connected to a known vacuum-forming assembly, which substantially provides for extracting the air from the deaerator.

The reference number 5 indicates a device for cutting the product into slices, also provided with a related motorisation 6, which originally slices the product (and does not triturate it as in the prior art) inside the deaerator, hence in an environment under vacuum.

The slices of product fall on a baffle 7, preferably having conical shape, whose function is to hold the slices in the environment under vacuum for a sufficient time (about 90 seconds) to allow its adequate deaeration, before the slices themselves fall laterally to the baffle towards a pump 8 that feeds the product to a dynamic mixer 9 provided with its own motorisation 10, in particular a gearmotor.

According to an alternative embodiment not illustrated herein, the baffle 7 can be replaced with a motorised auger for a precise control of the time of permanence of the slices in the deaerator.

The deaerated slices are free of air and hence suitable to retard the effect of

enzymes.

The dynamic mixer 9 is not strictly necessary for the method and the plant of the present invention, but if present it provides homogeneity of consistency to the pulp and an equal distribution of the components of the treated product, to favour the subsequent refinement in a substantially known refiner/strainer 11 (with a sieve having holes of about 0.5 mm diameter) wherefrom exits juice or puree that is sent to a steriliser 12 with integrated enzymatic deactivation which provides for the sterilisation and final cooling of the product under aseptic conditions.

In the preferred embodiment of Figure 2, the dynamic mixer comprises a rotor 13 with hexagonal cross section (Figure 2a), but it can more generally have polygonal cross section and in particular pentagonal or octagonal cross section as shown in Figures 2b and 2c, with preferably constant development and speed adjustable by means of the gearmotor 10. Said rotor rotates inside a stator 14 having substantially square cross section with preferably constant development.

In the gap 15 between rotor and stator, an adequate turbulence is created.

The method of the present invention thus originally provides a phase of slicing the product under vacuum, a possible mixing (in the dynamic mixer 9), followed by cold refinement and sterilisation-cooling which precedes the aseptic packaging of the final product.

The deaeration of the product occurs without heating, avoiding the loss of aroma encountered in deaerating procedures with heat.

The present method also allows to reduce and/or eliminate use of ascorbic acid or other anti-oxidation systems, as well as a reduction in processing times and energy consumption, maintaining a high efficiency of the method, of about 95%.