PROCESS FOR THE PREPARATION OF MILK PRODUCTS CONTAINING FRUIT USING DEHYDRATED FRUIT

Abstract: The present invention relates to a method for the preparation of dairy products with fruit, using dehydrated fruit in the form of powder, pieces or flakes, as well as a dairy product containing fruit, obtained using said method. The present invention also relates to a mixture comprising dehydrated fruit.

Description: Description PROCESS FOR THE PREPARAΗON OF MILK PRODUCTS CONTAINING FRUIT USING DEHYDRATED FRUIT 5 Technical Field The present invention relates to a method for the preparation of dairy products with fruit, using dehydrated fruit in the form of powders, pieces or flakes, as well as a dairy product containing fruit, obtained using said method. The present invention l o also refers to a mixture comprising dehydrated fruit. The use of fruit in the preparation of fermented and unfermented dairy products such as yoghurt, modified milk and soft cheeses is known. Background Art 15 According to the normal technique for the preparation of dairy products, the fruit may be added, for example, in the form of puree, pieces of fruit, fruit in syrup, depending on the type of product to be obtained. In the conventional technological cycle for the production of dairy products, it is important to use a milk with components such as water, carbohydrates, fats, 20 proteins, etc. present in percentages defined in order to characterise the product to be obtained. For this reason, such a technological cycle includes a step in which a given portion of water is eliminated either through evaporation or by adding a dehydrator, normally powdered milk, to the original milk. 25 Following this step, the cycle continues with a pre-heating step, in which the milk is brought to a temperature of between 60°C and 70°C. Pre-heating is followed by the homogenisation and pasteurisation step, during which the milk is brought to a temperature of between 85°C and 95°C, in order to eliminate any bacterial contamination. After pasteurisation and subsequent cooling, when preparing fermented dairy products such as yoghurt, milk enzymes are added. In an alternative technological cycle, the milk enzymes may be added immediately before final packaging of the product, by incubating and maturing the enzymes in the container for the end product. The milk enzymes may be those specific to yoghurt, or may be selected from other known strains, depending on the fermented dairy product to be obtained. In the conventional technological cycle for the preparation of dairy products with fruit, following the step of enzyme incubation, maturing and subsequent cooling, the dairy product obtained is mixed with a fruit preparation. The fruit preparation may take the form of a fruit puree or pieces of fruit. The fruit preparations used normally contain a given percentage of water and may be in a liquid or creamy form. Since, according to conventional techniques, such preparations are added in the dairy product production line immediately before packaging the end product, it is important that the preparations are made, packaged and preserved in strictly sterile conditions, and that such sterile conditions are also guaranteed during the step in which the above-mentioned preparations are inserted in the dairy products production line. It is important to avoid contamination with bacteria, which would be introduced into the packaged product, and the proliferation of the bacteria, in order to prevent fermentation, which would lead to an inevitable alteration in the properties of the end product. To avoid the above-mentioned contamination, according to conventional techniques the fruit preparations are produced then packaged in tanks with a given capacity, which must maintain sterile conditions both while they are being filled and during transportation of the fruit preparation to dairy product production facilities. Subsequently, to limit the risk of contamination during the step in which the fruit preparation is transferred to the dairy product production line, a complex device is normally employed, which uses inert gases to prevent air and any forms of bacteria from coming into contact with the fruit preparation. However, the technique described above is not without disadvantages. One disadvantage derives from the fact that, since the above-mentioned fruit 5 preparations contain a significant percentage of water for a given quantity of fruit, transportation and storage of the preparations involves the use of tanks with considerable capacities which are, therefore, very large. Another disadvantage is linked to the fact that, once the content of the tank has been used, the tank must be treated again, to restore the necessary sterile conditions l o before filling it again. The use of special tank sterilisation systems and the fact that such sterilisation treatments must be repeated each time the tank is used account for a significant part of the production costs of the end product. Another disadvantage linked to the use of tanks is due to the time for which the tanks must remain at the dairy product production system. The time for which the 15 tank is kept there may be considerable, since it depends on the operating schedules of the dairy product preparation system and does not always coincide with the fruit preparation production schedule, which depends on another system. This "down" time is also added to the time necessary to transport the tank back from the dairy product production line to the fruit preparation production line, with 20 a consequent slowing in the production line considered as a whole. A further disadvantage is linked to the fact that such fruit preparations have a limited shelf-life, due to the presence of water in the preparation. The fruit preparations must, therefore, be used within a short time of their packaging in the tank and partial use of the preparations at different stages must be limited, since the 25 connections to the system always introduce a risk of microbiological contamination. Yet another disadvantage is linked to the fact that the addition of the fruit preparations in liquid form does not allow inoculation of the enzymes immediately before packaging the end product. Some difficulty was encountered in the process of maturing enzymes in an environment in which such fruit preparations are present. Another disadvantage derives from the fact that, in order to introduce the preparation into the dairy product production line in sterile conditions, a complex device must be used, which has a significant effect on the cost of the system and, as a result, on the cost of the end product. To avoid the use of such a complex device, the dairy product production line could include a further heating, pasteurisation and cooling step, before packaging. Such steps would involve not only an increase in the preparation time required, but may also alter some of the organoleptic properties of the end product. The aim of the present invention is, therefore, to overcome the above- mentioned disadvantages by providing a method for the preparation of dairy products containing fruit, in which the fruit preparation is easily inserted into the dairy product production line. Another aim of the present invention is to provide a method for the preparation of dairy products containing fruit, in which the fruit preparation is easily transported and does not require special sterile packaging conditions. Another aim of the invention is to eliminate the use of tanks for holding the fruit preparation. Yet another aim of the method according to the present invention is to use a fruit preparation which has a longer shelf-life than conventional fruit preparations. Yet another aim is to avoid further pasteurisation steps, irrespective of the fruit preparation packaging, transportation and introduction conditions. Another aim of the present invention is to provide a simplified method for the preparation of dairy products containing fruit, which does not include additional steps for the removal of water through heating or the addition of powdered milk. Another aim of the present invention is to allow inoculation of the milk enzymes immediately before final packaging of the dairy product containing fruit. These aims and others, described in further detail in the description which follows, were fulfilled by the Applicant, who found it useful to use dehydrated fruit in the form of powders, pieces or flakes in the preparation of fermented and unfermented dairy products. Disclosure of the Invention Therefore, the subject matter of the present invention is a method for the preparation of dairy products containing fruit, whose basic characteristics are described in Claim 1. Also part of the subject matter of the present invention, is a dairy product containing fruit, obtained according to a method in which the fruit is added in the form of powder and/or pieces and/or flakes, as indicated in the independent claim below. The subject matter of the present invention also includes a mixture for the preparation of dairy products containing dehydrated fruit, as indicated in the independent claim below. Other preferred embodiments are described in the dependent claims. Further technical features and advantages of the present invention are more clearly described in the detailed description which follows. In accordance with the present invention, the fruit preparation to be inserted in the dairy product production line is dehydrated, thus being distinguished from the conventional preparation due to the almost complete absence of water. The dairy product may preferably be chosen from amongst fermented products, such as full fat yoghurt, low fat yoghurt and yoghurt with fruit, but also from amongst unfermented products such as milk which contains fruit and fruit- flavoured soft cheeses. In the method according to the present invention, the dehydrated fruit may be added in the form of powders and/or pieces and/or flakes. The dehydrated fruit in the form of powders, pieces or flakes may be obtained using any of the known drying methods. The powdered fruit may be obtained, for example, using methods such as grinding, drum-drying (drying on rollers or cylinders), spray-drying (drying by nebulising), freeze-drying, desiccation. The fruit powders are preferably obtained using drum-drying technology. The pieces of fruit are preferably dehydrated in hot air tunnels. The linear dimensions of the three-dimensional pieces may be between 1 millimetre and 15 millimetres. The flakes of fruit are preferably obtained through lamination of dehydrated products and the linear dimensions of the flakes, in which one dimension is negligible relative to the other two, may vary between 1 millimetre and 15 millimetres. The mixture for the preparation of dairy products with fruit, which is the subject of the present invention, comprises the above-mentioned dehydrated fruit combined with ingredients such as flavour enhancers, sugars, starches, maltodextrin, thickeners, gelling agents, natural and synthetic flavourings, natural and synthetic colours and stabilisers. The mixture comprising fruit in the form of powders, pieces or flakes used for insertion in the production line for dairy products preferably includes percentages of dehydrated fruit which vary from 50% to 95%, whilst the remaining part consists of the above-mentioned ingredients. The above-mentioned powder mixture, which constitutes the fruit preparation, is then packaged in aluminium barrier packaging, which may have various capacities depending on the quantity of the product to be sent to the dairy product production line. According to the method disclosed, in the dairy product production line, the milk is stored at a low temperature, for example between 2°C and 5°C, pre-heated then homogenised. In the method according to the invention, the fruit preparation in the form of powders, pieces or flakes is added after the homogenisation step. The fruit preparation is taken from the package whose capacity corresponds to the dimensions of the production line and is inserted, by means of a suitable doser, directly into the tank containing the milk. Special devices are not required, since the milk has not yet been treated to eliminate the presence of bacteria and their fermentation. It is after the mixing step, which may include the addition of powdered milk and some sugar, that the milk, along with its fruit content, is pasteurised, thus eliminating any bacterial contamination. After pasteurisation and subsequent cooling, an unfermented liquid product is obtained, based on milk and fruit, which can be packaged directly. In the case of a production line for a fermented dairy product, such as yoghurt, after the milk containing the fruit preparation has cooled, enzymes are added. Following the step of incubation of the enzymes added and their maturation, the fermented dairy product is cooled to a temperature of between 25°C and 40°C, packaged, cooled again to a temperature of between 1°C and 5°C then stored at a low temperature so that it is ready for final consumption. According to an alternative technological cycle, the dairy product containing fruit may be packaged immediately after the addition of the enzymes, by incubating and maturing the enzymes inside the container which holds the end product. The method according to the present invention does not require further sterile conditions during production, packaging and transportation of the fruit preparation, nor during its insertion in the dairy product production line. The fruit preparation is inserted before the pasteurisation step, which is the method normally used to prevent forms of contamination from both the milk itself and from the fruit preparation. After pasteurisation the dairy product can be packaged immediately. In the case of fermented end products, such as yoghurt, packaging takes place immediately after the addition and incubation of the enzymes, since the step of mixing with the fruit preparation took place before the pasteurisation step. Moreover, with the method disclosed, enzyme inoculation may take place immediately before packaging of the end product containing the fruit, since enzyme maturation is not hindered by the liquid containing the fruit preparation. Production of the dehydrated fruit preparation, together with the fact that sterile conditions are not required, is advantageous in that the preparation may be packaged in simple packaging, such as aluminium bags, which are economical, smaller and easily stored and transported. In contrast to the tanks, the bags may be made in different sizes, therefore with varying capacities, depending on the size of the system in the dairy product production line. Thus, the dairy product production line may be small or, in the case of large plant, small amounts of product may be required for industrial testing purposes. The packaging may, therefore, be selected according to the quantity of fruit preparation to be used, avoiding having to store the remaining part with the risk of deterioration of the properties of the preparation. Moreover, once the fruit powders have been added to the dairy product, the packaging may be eliminated, without necessitating its storage, its return with the relative transportation, or its cleaning and sterilisation. Another advantage of the method disclosed is linked to the fact that the powdered fruit has a longer shelf-life than creamed fruit, therefore, reduced deterioration of some ingredients and of the organoleptic properties not only of the preparation, but also of the end product. The dehydrated fruit preparation may also be preserved at temperatures approaching room temperature without requiring special devices for its preservation. Moreover, the fact that the fruit powders are mixed with the milk before pasteurisation allows elimination of the step of removing water by heating or by adding powdered milk, since the milk is concentrated simultaneously with the addition of the fruit powders. The method disclosed also allows the use of a simplified system for the preparation of dairy products, since there is no need to use complex devices to transfer the preparation to the production line in sterile conditions. The invention described can be subject to numerous modifications and variations without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements. Claims 1. A method for the preparation of a dairy product containing fruit, characterised in that the fruit is added in dehydrated form. 2. The method according to claim 1, characterised in that the dehydrated fruit is in the form of powders. 3. The method according to claim 1 , characterised in that the dehydrated fruit is in the form of pieces. 4. The method according to claim 1 , characterised in that the dehydrated fruit is in the form of flakes. 5. The method according to any of the foregoing claims, comprising the following steps: a) homogenisation of the milk; b) addition of the dehydrated fruit; c) pasteurisation of the milk; and d) cooling of the milk obtained from step c). 6. The method according to claim 5, further comprising the following steps: e) addition of milk enzymes; f) incubation of the milk with added milk enzymes, to obtain a fermented dairy product containing fruit. 7. The method according to any of the foregoing claims, further comprising a step of packaging the dairy product containing fruit.

Claims: 8. The method according to claim 7, characterised in that the packaging step occurs before the incubation and subsequent maturation of the milk enzymes. 9. The method according to any of the foregoing claims, wherein the dairy product is a fermented product. 10 The method according to claim 9, wherein the fermented product is yoghurt. 11. The method according to any of the foregoing claims, wherein the step of adding the dehydrated fruit is carried out by taking the dehydrated fruit from aluminium barrier packaging directly available on the dairy product production line. 12. The method according to any of the foregoing claims, wherein the dehydrated fruit is combined with one or more compounds selected from the group comprising sugars, flavour enhancers, starches, maltodextrin, thickeners, gelling agents, flavourings, natural colours and stabilisers. 13. A dairy product containing fruit, characterised in that it comprises dehydrated fruit, added during production. 14. The dairy product according to claim 13, characterised in that the dehydrated fruit is in the form of powders. 15. The dairy product according to claim 13, characterised in that the dehydrated fruit is in the form of pieces. 16. The dairy product according to claim 13, characterised in that the dehydrated fruit is in the form of flakes. 17. The dairy product according to any of the foregoing claims from 13 to 16, obtained using a method which comprises the following steps: a) homogenisation of the milk; b) addition of the dehydrated fruit; c) pasteurisation of the milk; and d) cooling of the milk obtained from step c). 18. The dairy product according to claim 17, obtained using a method which also comprises the following steps: e) addition of milk enzymes; f) incubation of the milk with added milk enzymes, to obtain a fermented dairy product containing fruit. 19. The dairy product according to any of the foregoing claims from 13 to 18, characterised in that the dairy product is a fermented product. 20. The dairy product according to claim 19, characterised in that the fermented product is yoghurt. 21. A mixture for the preparation of dairy products, characterised in that it comprises: a) dehydrated fruit; b) flavour enhancers; c) sugars; d) maltodextrin; e) flavourings; f) natural colours; g) stabilisers; h) starches; i) thickeners; 1) gelling agents. 22. The mixture according to claim 21, characterised in that the dehydrated fruit is in the form of powders. 23. The mixture according to claim 21, characterised in that the dehydrated fruit is in the form of pieces. 24. The mixture according to claim 21, characterised in that the dehydrated fruit is in the form of flakes.

Inventors: BETTARELLO ANTONIO, NANNI TEODORICO, BETTARELLO, ANTONIO, NANNI, TEODORICO
Applicants: BETTARELLO ANTONIO, CAPUZZO S R L, NANNI TEODORICO, BETTARELLO, ANTONIO, CAPUZZO S.R.L., NANNI, TEODORICO
Application year: 2001
Main classification: A23C9
IPC codes: A23C9, A23C19