DESCRIPTION

The present invention relates to a process for freezing fruit and vegetable juices. A further object of the present invention is a production process of packaged fruit or vegetable juices and a frozen fruit or vegetable juice obtained according to the process.

The prior art includes various processes and machinery suitable for freezing comestible liquids.

Some of the known processes and machinery for freezing comestible liquids are concerned with realising frozen or deep-frozen products destined for consumption of products directly in the frozen form, for example iced lollies, crushed-ice drinks (granite) and the like.

In the case in which comestible liquids are destined for consumption in the liquid form, the liquids are instead normally packed and conserved in a protected environment at room temperature or at sufficiently low temperatures, while being kept in the liquid form.

The freezing of comestible liquids is in fact often difficult, especially for some types of comestible liquids, as the freezing and subsequently the defrosting process has some drawbacks and requires very restrictive and specific operating parameters in order to be carried out in an optimal way.

For example, some types of comestible liquids are subjected, during the freezing process, to a separation of some components thereof, and even to the separation of a watery component from other components, therefore leading to a poor homogeneity and an insufficient quality of the comestible liquid when later defrosted.

Further, various processes and machinery of known type do not have the necessary freezing efficiency or the necessary functioning parameters, for example in terms of freezing temperature or rapidity of defrosting, leading to a qualitative decay of the resulting product.

Further, various processes and machinery of known type lead to realising compact blocks of frozen comestible liquid, which therefore require a considerable time to be returned to liquid form or even require a heating thereof, with a consequently awkwardness of use and a further qualitative decay of the product.

Further, the processes and machinery for freezing of known type do not normally enable a homogeneous freezing of the substances.

A machine for freezing in the form of flakes of some types of liquid substances has been proposed, in particular salt water, fresh water and animal milk, which at least partly obviates the above-cited drawbacks. This machine is disclosed in Italian patent IT1389280. The parts of the patent which describe the machine and in particular the structural components of the machine, such as the roller, the cooling system of the roller and the ice-breaking members are incorporated for reference in the present description.

As regards, on the other hand, the fruit and vegetable juices, many known processes include maintaining the juices in the liquid form, by addition of preservatives, by means of an appropriate packaging system, preferably in a protected environment, or by conservation at low temperatures for limited times. Also known are processes that include freezing of the fruit or vegetable juices, but these processes and machinery have the above-cited defect of creating compact blocks of frozen liquid substance and further normally separate the watery component from the pulp, the juices and other components, leading to a significant qualitative decay of the juices. In particular this separation is particularly undesirable as it compromises the quality of the juice and further, when being defrosted, the two components are separated. Further, the frozen and subsequently defrosted juice normally loses, due to the modes and times of the juice extraction process and the freezing process, as well as the modes, the temperatures and the defrosting times, a relevant quantity of nutritional elements subject to rapid degradation following the extraction thereof. The defrosted fruit and vegetable juice does not therefore have the same quality as freshly-squeezed juice.

In the light of the above, a principal aim of the present invention is to obviate one or more of the drawbacks encountered in the prior art.

An aim of the present invention is to make available a process for freezing fruit and vegetable juices that is simple and effective. A further aim of the present invention is to make available a process for freezing fruit and vegetable juices that is able to maintain the nutritional properties of the frozen fruit and the subsequent defrosted product unaltered.

A further aim of the present invention is to make available a process for freezing fruit and vegetable juices that can be carried out with the same efficiency starting from various types of fruit and vegetables and with a plurality of extracted juices. A further aim of the present invention is to make available a process which enables freezing fruit and vegetable juices homogeneously, without any formation of non-homogeneous zones in the frozen product and the subsequent defrosted product.

A further aim of the present invention consists in making available frozen fruit or vegetable juices which can be defrosted and made ready for consumption in a liquid form in very rapid times and with a simple defrosting process.

A further aim of the present invention consists in making available frozen and packaged fruit or vegetable juices which can be defrosted and made ready for consumption in a liquid form in very rapid times simply by placing them at room temperature for a limited time. An additional aim of the present invention is to guarantee a rapid and optimal freezing of fruit and vegetable juices, so as to obtain frozen products that have intact and/or substantially unaltered nutritional properties with respect to the step preceding the freezing, and in particular with respect to the juices when freshly extracted. A further aim of the present invention consists in making available frozen and packaged fruit or vegetable juices which enable an easy verification of the correct state of conservation thereof.

A further aim of the present invention is to enable drinking, after even a considerable time, fruit and vegetable juices having substantially identical quality to a juice freshly squeezed or extracted, with organoleptic and nutritional qualities that are unaltered and having substantially the same flavour.

These objects and others, which will appear more clearly from the following description, are substantially attained by a process for freezing fruit and vegetable juices, by a process for production of packaged fruit and/or vegetable juices and by a fruit or vegetable juice according to what is set out in one or more of the appended claims and/or the following aspects, taken alone or in any combination with one another or in any combination with any one of the appended claims and/or in combination with any one of the further aspects or characteristics described below.

In an aspect, combinable with any one of the claims and/or aspects described in the following, the invention further relates to a process for freezing fruit and vegetable juices comprising at least the steps of extracting a juice from and/or vegetable products and freezing the juice to realise a plurality of flakes of frozen juice having a thickness of less than 10mm.

In a further aspect of a process according to the invention, the flakes are realised with a thickness of less than 8mm, or less than 6mm, or less than 5mm, or less than 4mm, or less than 3mm.

In a further aspect of a process according to the invention, the flakes are realised with a thickness comprised between 8mm and 0.5mm, or comprised between 6mm and 1 mm, or comprised between 5mm and 1.5mm.

In a further aspect of a process according to the invention, the step of freezing at least a layer of juice is realised within 60 minutes from the step of extraction of the juice from the fruit and/or vegetable, in particular within 30 minutes or 20 minutes or 15 minutes, preferably within 10 minutes or within 5 minutes or within 1 minute or within 30 seconds.

In a further aspect of a process according to the invention, the time interval in which the step of freezing the layer of juice is less than 20 seconds or than 15 seconds or than 10 seconds or than 5 seconds or than 3 seconds

In a further aspect of a process according to the invention, the step of freezing at least a layer of the juice is carried out at a temperature comprised between -12 °C and 0 °C, or between -3°C and 0°C, in particular at a temperature of lower than or in proximity of or lower than and substantially equal to 0°C.

There now follows, by way of non-limiting example, a detailed description of one or more preferred embodiments of the invention, in which:

figure 1 is a schematic side view of the freezing machine in the form of flakes of liquid substances configured for implementing the process according to the present invention;

figure 2 is a front view of the machine of figure 1 .

With reference to the figures, 1 denotes in its entirety a freezing machine in the form of flakes of liquid substances. In particular, the machine 1 is configured for freezing fruit and vegetable juices in the form of flakes. The machine 1 comprises a container 2 for a juice extracted from fruit or vegetables and a roller 3 that is rotatable relative to the container 2. The machine further comprises a cooling device of the roller 3, realised internally of the roller itself, at least an ice-breaking member 4, able to break a thin sheet of frozen liquid formed on the surface of the roller, at least a removal element 5 of the flakes of juice formed and a collecting element 6 for the flakes detached from the roller. The cooling device, of a known type from patent IT1389280 and therefore not illustrated in greater detail in the present description, is configured for cooling an external surface 3a of the roller 3 by means of a coolant fluid, preferably a gas, for example Freon 404, operating at a suitable temperature. For example, the coolant fluid can operate at a temperature comprised between -16°C e -20°C. The machine 1 can further be operatively connected to a juice extractor device 7. The juice extractor device 7 is supplied with fruit or vegetable 7a and is configured for extracting a quantity of juice from the fruit or vegetable 7a. The extractor device 7 further comprises an operating section 7b, of a known type and therefore not illustrated in greater detail in the present description, which enables extraction of the juice. The operating section 7b is configured for extracting juice from the fruit or vegetable preferably by cold-extraction (or cold squeezing) or, alternatively, by centrifugation. Cold extraction owes its definition to the fact that it does not heat up the fruit of vegetable from which it extracts juice and therefore the juice extracted therefrom is substantially at room temperature or in any case at the initial temperature of the fruit or vegetable. The juice extractor device 7 enabling cold-extraction works at a low number of revolutions per minute (for example below 100 rpm), not causing overheating of the juice. In this way, the cold-extraction enables maintaining the enzymes, vitamins and all the micro-nutrients of fruit and vegetables "alive" (in a good state). Centrifugation on the other hand represents a mode of extraction of juice from fruit and vegetables which is carried out at rotational velocities that are faster than the rotational velocities typical of cold-extraction. Centrifugation usually causes an increase in the temperature of the juice due to the high rotational velocities. Alternatively the juice extractor device 7 can include other modes of obtaining the juice, for example, by whipping or compressing the fruit or the vegetable, etc..

Following the extraction of the juice, the juice is collected from the extractor device 7 and immediately sent, for example by means of a supply channel 8, to the container 2 of the freezing machine 1 . The container 2 comprises a level sensor 2a configured for detecting the reaching of a predetermined level of juice in the container 2. The level sensor 2a is further configured for interrupting the supply of juice to the container 2 and/or the extraction of the juice when the juice reaches the predetermined level. The time interval which goes from the extraction of the juice to the sending thereof into the container 2 is advantageously as short as possible, preferably in the order of minutes or even more preferably in the order of seconds. The time interval can for example be equal to or lower than 20 minutes or 10 minutes or 5 minutes or 3 minutes or 1 minute or 30 seconds or 10 seconds or 5 seconds.

As illustrated in figure 1 , in operating conditions of the machine 1 the roller 3 rotates partly in contact with the juice contained in the container 2. The juice in contact with the refrigerated external surface 3a of the roller 3 freezes and forms a frozen layer 9 of juice. The freezing of the juice is done at a temperature of lower than or equal to 0°C. For example the freezing is done at a temperature comprised between -20°C and 0°C, or between -12°C e 0°C, preferably at a temperature comprised between -3°C and 0°C. The freezing of the juice is preferably carried out at a temperature comprised between -1 °C and 0°C or substantially equal to 0°C. This freezing mode of the juice prevents a separation of the juice into various components. The layer 9 of frozen juice is thin and can have a thickness of the order of a few millimetres. A thin thickness of the layer of frozen juice is advantageous as it does not determine the formation of voluminous frozen blocks of juice and therefore the volume of the frozen juice is reduced and the conservation and storage thereof is simplified. The rotation velocity of the roller 3 can be modulated in order to regulate the thickness of the frozen layer 9. In particular, the lower the rotation velocity of the roller 3 the longer the contact time of the juice with the refrigerated surface 3a of the roller 3 and therefore the greater the thickness of the layer 9 of frozen juice which forms on the roller 3. Limiting the thickness of the layer 9 of frozen juice is particularly advantageous as it enables both a rapid freezing and a subsequent rapid defrosting. The freezing of juice in contact with the roller 3 is done in a very short time, for example less than 20 seconds, or less than 15 seconds, or less than 10 seconds, in particular less than 5 seconds or 3 seconds. Between the step of extraction of the juice from the fruit or vegetable and the step of freezing the juice on the refrigerated surface 3a of the roller 3 a time interval as short as possible passes, preferably less than 60 minutes or 30 minutes, in particular less than 20 minutes or 15 minutes. The time range is preferably lower than 10 minutes or 5 minutes or 1 minute.

The time range is advantageously kept short with the aim of preventing excessive oxidation of the just-squeezed fresh juice. The oxidation of the juice is particularly undesirable as it determines a deterioration of the nutritional elements of the juice (such as vitamins).

Following freezing thereof, the layer 9 of frozen juice is solidly constrained to the roller 3. The rotation of the roller 3 takes the frozen layer 9 to the ice-breaking member 4, which is provided with blades and longitudinally grooves the frozen layer 9. The ice-breaking member 4 therefore determines the partial formation of flakes of ice 10. The ice-breaking member 4 is configured to rotate, for example in the opposite direction to the roller 3. The ice-breaking member 4 comprises a plurality of blades, for example eight blades, and is configured for functioning without clogging for up to many consecutive hours.

The partly-fractured frozen layer 9 impacts against the removal element 5, which determines the completion of the formation and the detaching of the flakes 10 of juice from the roller 3. The removal element 5 can be fixed, adjustable or mobile with respect to the roller 3, and can be constituted for example by a plate or blade substantially in contact with the rotating roller. The flakes 10 removed from the roller 3 thus deposit on the collecting element 6, which can comprise a slide (see figure 1 ) able to take the flakes of juice towards a subsequent packaging step. A freezing machine 1 that can be advantageously used for realising the process of the present invention is the one described in Italian patent IT1389280.

According to an embodiment, the extractor device 7 and/or the freezing machine 1 can operate in predetermined environmental conditions, appropriately configured for reducing the oxygenation of the juice and the deterioration thereof. For example the environmental conditions can comprise a temperature and/or a controlled humidity and/or a "protective atmosphere". In this way, the extraction and freezing of the juice take place at a temperature and/or controlled and ideal humidity for fruit and vegetables under process. By operating at a controlled temperature, the fruit or vegetable is prevented from being subjected to thermal shocks which might damage its nutritional properties.

The flakes 10 of juice frozen in this way can be packaged in order to enable a subsequent consumption thereof. The packaging can also take place in a protective atmosphere. The packaging can be of a single-dose or multi-dose type. The packages can be conserved in a refrigerated environment (such as refrigeration cells) for example at a temperature comprised between -16°C e - 18°C. The temperature range is ideal for the conservation of the flakes 10 of frozen juice. In the conservation cells of the flakes 10 of frozen juice, the temperature preferably should never near the temperature of 0°C, at which the flakes can begin to thaw, and preferably the temperature must never rise above - 5°C, so that the flakes of ice 10 are not exposed to thermal shock and do not thaw. The packages can be conserved for a time range in line with what is set down in the existing reference standards for the conservation of the food products.

When required, the packages are defrosted and the flakes 10 return to the liquid state, and the thawing of the flakes can take place simply and rapidly, including only placing the flakes at room temperature or in any case at temperatures above 0°C for a short time. The fruit or vegetable juice, thus-defrosted, substantially maintains its nutritional and organoleptic properties intact and therefore has a similar and comparable quality to that of freshly-squeezed juice. In an alternative embodiment, the freezing can take place in a different machine from the one illustrated, as the freezing mode of the juice in terms of time, temperature of freezing and flake shape assumed by the frozen juice are as described in the foregoing.

The present invention makes it possible to obtain one or more of the following advantages and to resolve one or more of the problems encountered in the prior art. Primarily the invention enables rapidly and effectively freezing fruit and vegetable juices without any loss of the nutritional properties thereof. The freezing process according to the present invention enables formation of a frozen product having a homogeneous composition. The freezing achieved by means of the freezing machine described does not lead to the separation of the watery phase from the phase that comprises the pulp and therefore the frozen juice is homogeneous. Further, as it is frozen in the form of slim flakes, the juice is defrosted rapidly and is immediately ready to be easily thawed and drunk or used in other ways. By freezing the fruit and vegetable juice in the form of flakes, the volume of the frozen product is reduced, and is not constituted by a single frozen block of juice but by slim flakes, which can be packaged in many different ways. Further, by means of the process of the present invention, the fruit and vegetable juices advantageously maintain the quality thereof and the flavour thereof when later defrosted. The invention further enables increasing the safety of use of the comestible product, as it enables easy checking of the qualitative integrity of the product. In fact the permanence of the product in the form of flakes confirms that the product has been correctly conserved, while any transformation of the product into the form of blocks of significant dimensions, or partially-thawed agglomerations, provides the consumer with an immediate reference relating to the incorrect conservation of the product, thus eliminating or reducing the risk that deteriorated products can be consumed, of poor quality and potentially dangerous to health.

A further advantage is given by the fact that the process enables realising and freezing the fruit and vegetable juices in proximity of the places of production of the fruit and vegetables, using high-quality fruit and ripened in the best way, and optimising the transport of juices obtained from the high-quality fruit in any part of the world, even at great distances. In this way it is possible to reduce the transport costs of the fruit destined for obtaining the juices and it is possible to reduce the use of fruit which is collected before ripening, so as to take account of the time necessary for transport thereof to the destination.

The invention is moreover convenient to use, easy to implement and simple and economical to make.