PT107016A - PROCESS FOR THE PRODUCTION OF FERMENTED DAIRY PRODUCTS BASED ON LIQUID CONCENTRATES OF SERUM PROTEINS - Google Patents

Abstract

The present embodiment relates to the use of liquid concentrates of protein of the serum (CLPS) and of concentrated ultrafiltration (PUFC) in the production of dairy foods, in particular, fermented dairy beverages. CLPS IS OBTAINED THROUGH THE CONCENTRATION OF MILK SERUM BY ULTRAFILTRATION (UF), THERMAL DENATURATION OF THE PROTEINS OF THE CONCENTRATE OBTAINED AND ITS SUBSEQUENT HOMOGENIZATION. DURING THIS PROCESS ALSO OBTAINED A UF PERMEATE THAT IS LATER THAN CONCENTRATED BY INVERSE OSMOSIS (OI), WHICH IS ALSO USED IN THE PREPARATION OF FERMENTED DAIRY DRINKS. THE PROCESS ALLOWS THE TOTAL USE AND REVALORIZATION OF THE DAIRY SERUM, MAIN BYPRODUCT OF THE LACTICINO INDUSTRY AND ONE OF THE GREATEST ENVIRONMENTAL POLLUTANTS ORIGINATED BY THIS INDUSTRY. IN THE EVENT, AND DUE TO LOW IMPLEMENTATION COSTS, THIS PROCESS MAY BE USED IN SMALL / MEDIUM-SCALE INDUSTRIES.

Description

A process for the production of fermented dairy products based on liquid whey protein concentrates "

TECHNICAL FIELD The present invention relates to the use of liquid whey protein concentrates (CLPS) and concentrated UF permeate (PUFC) in the production of dairy products, in particular fermented dairy drinks.

Background Lactose is a by-product of the cheese industry whose residue processing is impractical because of its high biochemical oxygen shortage (CBOs = 35-45 g / L) (Marwaha & Kennedy, 1988). The non-valuation of this by-product in an industrial facility with a daily production of 1,000,000 liters would be responsible for the contamination, in terms of population equivalent, to about 400 to 450 thousand inhabitants. By population equivalent, biodegradable organic matter with a biochemical oxygen demand (CB05) of 60 g 02 per day, 64 g COD / day (chemical oxygen demand per day) or 57 g MO / day (organic matter / day). This parameter represents the population that would produce pollution wastewater equivalent to the industrial discharge that is intended to be evaluated (in CBO5) and which allows comparatively to have a notion of the polluting potential of the effluents generated by the industrial units. In concrete terms 100 kg of liquid whey have a pollutant force equivalent to the debris produced one day by 40-45 people.

Every year in Portugal the cheese industry produces on average about 77,000 tonnes of cheese (INE, 2010 and 1 2012), which corresponds to an annual production of about 691 million liters of lactose. In Europe, cheese production is on average 9,187 thousand tonnes (EDA, 2012), corresponding to 82,683 million liters of lactose which can be recovered.

Dehydrated whey protein concentrates (CPS or WPC) are widely used as ingredients in a wide range of food products (Diaz et al., 2009) because of their specific functional and nutritional characteristics. However, the production of dehydrated whey protein concentrates (with 34, 50, 60 or 70% protein in the dry basis) or serum protein isolates (with more than 90% protein in the dry basis) is usually associated to large industrial units. For economic and scale reasons, small and medium-sized industrial plants can not adopt the same technology strategy, which presents difficulties in the treatment and / or use of this by-product, since the serum can not be directly disposed of in the legal requirements, nor can it be treated in a WWTP due to technical and operational constraints. Under these conditions, small and medium-sized industrial plants have been obliged to dispose of it for animal feed or to concentrate it by reverse osmosis (01) by selling it (for values below the cost of production) to large units dehydrate, most often producing whey powder with about 10% protein and a market value of about 1,200 € / ton.

In any situation, the cheese producing units do not take any advantage of the nutritional and functional potential of this product and, in most cases, the problem resolution is seen as an additional cost of production. The solution proposed here, which allows the valorization and internal use of the whey, besides adding value, will allow these units to diversify their range of products and reduce costs with raw materials. In units that have already made investments to acquire systems of 01 to concentrate the serum seems to be evident the greater interest in reverting to their own advantage the added value that will be generated by the proposed technology and its products qerados. The industrial production of dairy products such as yogurts or fresh cheeses involves the standardization of milk solids content (usually their increase) in order to prevent the spontaneous separation of serum (syneresis) considered as a defect in these products (Lucey, 2004). Amatayakul et al., 2006). This operation is usually carried out in a mixing tank, with several dehydrated ingredients being added to the manufacturing milk. In the case of yoghurt production, lean milk powder is commonly used although fat milk powder, caseinates or whey protein concentrates may also be used (Lucey 2002, Tamime & Robinson 1999). These products are purchased on the market in the form of dehydrated products at very high prices (> 2,000 € / tonne). Recovery of the soluble proteins present in the serum can be effected in a simple manner by the production of aggregates of whey proteins. In Portugal, the production of curd is a process that has been applied for many years. Although its application is empirical, the production of this product is based essentially on the effect that the heating produces on the 3 whey proteins causing their gelation and the formation of protein agglomerates that retain other components present in the serum, namely fat . Havea et al. (1998) report that whey proteins when heated under appropriate conditions (> 75øC, pH between 6-8 and at concentrations greater than 6g / 100g) form a gel. However, the sorghum (residual whey from the manufacture of curd) continues to present a considerable organic load and can not be discarded in the environment without previous treatment (Pereira et al., 2002). The integration of an ultrafiltration (UF) step of the serum into industrial units is an economically attractive alternative that allows the production of whey protein concentrates which can be subsequently dehydrated or immediately incorporated into the manufacture of other food products.

A number of papers and patent documents are published that study the process or are intended to define the processing conditions and the products to be obtained. However, with the particularity of the final products presented in the dehypedatode form. Recent examples include the following documents: WO 2008/063115 A1 describes a method for the application of processing conditions allowing the preparation of dehydrated microparticulate whey protein concentrates and suggests their use as an ingredient in cheeses , yogurts or other foods. Essentially the process aims at denaturing the whey proteins under high temperature (> 100 ° C) and high pressure conditions. The heat treatment process they exhibit is carried out continuously and under conditions different from those of the present embodiment. As the basic raw material, UF-concentrated whey (as in the present invention) or dehydrated serum protein concentrates previously reconstituted in water may be used. The differences between the production process reported in that document and the claims of the present proposal with respect to the operational conditions of the final heat treatment (temperature and pressure much higher) are evident. It should also be pointed out that the use of the product resulting from the technology as the main raw material of a dairy product is not claimed, but only as an ingredient to be used in food products. WO 2010/120199 AI discloses a method starting from an aqueous solution of whey protein concentrate having protein values between 15 and 50% (w / v). This solution can be prepared from dehydrated whey protein concentrates (CPS) or dehydrated whey protein isolates (IPS) by reconstitution with water, or from ultrafiltration retentate of evaporated whey in order to increase the protein content). The protein concentration of this product is clearly superior to that of the products to be obtained by applying the technology of the present application, as will be seen in Table 1. In terms of the technology claimed in WO 2010/120199 A1, protein denaturation is made under high temperature conditions but without the use of a homogenization process. Once again the objectives are to obtain a concentrate of denatured whey proteins. For any of the base stock situations referred to herein, the protein values to be obtained are much higher (15-20% m / v) than those resulting from the present embodiment (6-10% m / v). It is further noted that in WO 2010/120199 A1 the product obtained is dehydrated for further application and may under certain conditions be used directly as an ingredient in other food products in order to increase the protein content of the products to which it is incorporated or to be a protein concentrate which serves as the basis for the production of hydrolyzates of whey proteins. Again, its use as a main raw material in the production of fermented milk drinks is not mentioned.

Other patent documents may be referred to, in particular: - WO 2007/03296 AI - for equipment intended for the denaturing of whey proteins by heat; EP0412590 and EP0347234 relating to the process for the preparation of microparticulate whey protein dispersions; WO 2006/057968 relating to the processing of cream cheese using denatured whey protein concentrates; or DD236449, for obtaining colloidal suspensions of thermally stable whey proteins; US 5,494,696 relating to the process of treating protein solutions of whey with 65-95% protein in the dry base which are denatured by direct injection of steam and are also homogenized.

In all these cases the minimum heat conditions required for the denaturation of the proteins vary according to other processing conditions, namely pressure and fluid flow conditions. In some cases, the products obtained are subsequently dehydrated while in others they can be directly integrated into the process of producing other foods. In none of the cases where the ultrafiltration (UF) process is used with the aim of concentrating the whey protein fraction are applications reported for the UF permeate fraction. It should be noted that WO 2011/005128 A2 advocates the direct fermentation of the permeate with kefir grains in order to prepare a dairy beverage. However, the present invention advocates the production of a reverse osmosis concentrated ultrafiltration permeate (PUFC) (Table 3), with a differentiated composition of the former, before being subjected to the fermentative process by commercial probiotic strains, kefir grains exclusive, together or separately, or by acidification with glucono-5-lactone (GDL).

In practice, if only kefir grains are used to promote fermentation, the product resulting from the process now shown will have a residual lactose content higher than that of WO 2011/005128 A2, and "body" and a higher viscosity.

In the case of the production of fermented beverages based on probiotic bacterial strains, no reference to their production was identified using UF-permeated concentrate by reverse osmosis added with fruit pulp.

Several authors report the possibility of adding whey proteins to the milk used in cheese making (Abrahamsen, 1979; Banks & Muir, 1985; Baldwin et al., 1986; Korolczuk & Mahaut, 1991a, 1991b; Mahaut & Korolczuk , Smith (1996), Jameson and Lelievre (1996), Lebeuf et al (1998), Perez-Munuera and Lluch (1999) and Hinrichs (2001). The main topics and conclusions can be summarized as follows: (1) the importance of denaturation of the whey proteins to ensure their incorporation into the protein matrix of the cheese; (2) the importance of the dimensions of protein concentrates; (3) increasing the water retention capacity of cheeses; (4) the lower acidification of the cheeses produced due to the greater buffering power of the whey proteins; (5) the occurrence of differences in flavor and aroma of the modified products; (6) the optimal amount of concentrate incorporation.

Although there is some information on the use of CLPS in cheeses, its direct use as a starting material in the manufacture of fermented dairy products is not mentioned. In the present study, the effect of dehydrated whey protein concentrates (CPS or WPC) on the physicochemical and sensory characteristics of solid yoghurts (Guzmán-González et al., 1999; Sodini et al., 2005 and 2006 , And Pikul et al., 2006).

In the case of the application of CLPS in yogurts, the authors of the present realization have already published information regarding their use as a partial substitute (up to a maximum of 30%) of the milk used in the manufacture of yogurts (Henriques et al., 2011; 2012).

Previous work aimed to replace part of the milk used in yogurts with a by-product of high nutritional value. The main objective being the utilization of the by-product and simultaneous reduction of production costs by reducing the use of milk. It also added to the potential nutritional enrichment of 8 yogurts by using higher percentages of proteins with higher biological value. It should be noted that it was clearly intended that consumers should not detect organoleptic differences between conventional and CLPS-enriched products. The fact that milk is not used and consequently ceases to be caseins to contribute to the protein matrix of yoghurts is, in the first instance, changes in the texture of the products to be obtained. Of course, products obtained by this route can not achieve the firmness typical of a conventional solid yogurt.

Other documents refer to the formulation of liquid yogurts with higher proportions of whey proteins than those found in milk. In the case of US 2011/0217416 A1, the ratio of whey caseins / proteins is changed to values between 4:96 or 12:88, as it is based on altering the proportions of caseins and whey proteins by the preparation of a milk mixture obtained by the dissolution in water of caseinates and / or whey protein concentrates as well as components containing milkfat such as cream or fat milk powder. That is, it is not part of whey that, after concentration by UF and thermal denaturation, becomes the main ingredient of manufacture, and that is something that the present embodiment allows.

Another example is that described in US 2011/0097442 Al which, using various membrane filtration techniques, fractionates the serum into different products which, after suitable treatment, can be used as dairy drinks. Microfiltration, ultrafiltration and nanofiltration techniques are used to fractionate various protein components present in lean milk in order to obtain a final product with a whey / casein protein ratio of from 90:10 to 50:50 and a content of protein of the order of 20% on the dry basis. It should be noted that the process is based on obtaining whey from lean milk, which is not the result of the manufacture of cheese. US 2012/0189737 AI is also another example relating to the use of whey in the production of dairy drinks. In this case a mixture of acid whey, caseins, whey proteins and carbohydrates is used in order to give a base formulation with a casein / whey protein ratio between 0.5: 99.5 and 12:88. It is subsequently acidified with a food acidifier followed by acidification by a microbial culture. The same observation applies to US 2007/0065560. The present invention allows to obtain products having the characteristics of creamy yogurts whose texture can be manipulated either with the addition of small amounts of milk powder or with the variation of the fat content of the product. In addition, the addition of fruit pulp or aroma, sugar and / or other flavors and, optionally, the use of thickening gums also allow manipulation of this parameter according to the desired characteristics.

The characteristics of the products obtained from the use of CLPS have shown that by manipulating some ingredients or adding adjuvants it is possible to obtain products with sensorial characteristics very similar to conventional yoghurts and liquid fermented or solid milk products, and as such organoleptic characteristics well accepted by consumers. It is to be noted that the present embodiment describes the full use of CLPS or the use of reverse osmosis concentrate ultrafiltration (PUFC) permeate as the base raw material in the production of fermented or acidified dairy products using a proprietary kefir culture or using a mixture of this culture with commercial strains of bacteria with probiotic activity.

Thus, the direct use of CLPS or PUFC combined with the use of a specific and exclusive culture that is owned by the inventors (alone or in combination with commercial probiotic strains) makes the products innovative and unique.

summary

In the present embodiment an innovative process is described which allows the total recovery of the lactose, the main by-product of the dairy industry, which is highly polluting and whose processing as waste is very expensive. This innovative process results in two products: liquid whey protein concentrate (CLPS) and concentrated UF permeate (PUFC) which are the raw material for the manufacture of dairy products, in particular fermented dairy drinks.

Accordingly, it is the object of the present application to describe a process for the production of dairy products, which comprises the following steps: - ultrafiltration of lactose, from which the liquid whey protein concentrate (CLPS) and the permeate result; - CLPS thermal treatment, subsequent homogenization and cooling of the CLPS, and - concentration of the inverse osmosis ultrafiltration permeate and obtaining the concentrated ultrafiltration permeate (PUFC), - inoculation and fermentation of CLPS and PUFC with kefir, lactic acid bacteria and / or their mixtures; cooling to a temperature below 20 ° C for a period of less than 1 hour.

In a preferred embodiment of the milk product production process, the heat treatment of the CLPS is carried out at a temperature between 85-95 ° C for at least 5 minutes and cooling takes place at a temperature of 70 ° C.

In another preferred embodiment of the milk product production process, the homogenization of the CLPS is carried out under a pressure of 50 to 100 bar.

In yet another preferred embodiment of the dairy product manufacturing process, the CLPS or the PUFC are added ingredients selected from a group comprising: milk powder, sugar, fruit flavors or preparations and the adjuvants are selected from thickening gums , whole or skimmed milk powder. 12

In a preferred embodiment of the dairy product production process, the mixture of PUFC and added ingredients is homogenised at 50 bar and heated to 75øC for a period of 30 seconds.

In another preferred embodiment of the dairy product production process, the lactic acid bacteria are selected from a group comprising a specific culture of kefir grains (CIDCA AGK1), alone or in combination with lactic acid bacteria such as:

Lactobacillus acidophillus, Lactobacillus rhamnosus,

Lactobacillus casei, Lactobacillus plantarum or mixtures of these strains.

In still another preferred embodiment of the dairy product production process, the fermentation takes place until a pH of 4.5 is achieved.

In a preferred embodiment of the milk product production process, the rapid cooling is effected through a cooling tunnel or in a tubular exchanger. It is a further object of the present invention to describe the dairy products obtained by the process described above, in which they have: a protein matrix comprising 90% to 100% whey proteins when obtained from CPLS with Lactococcus counts spp. and Lactobacillus spp. and of yeasts greater than 1,000,000 CFU / g, and the following physicochemical composition: 13 - Total solids between 15 and 20%; - Protein between 6 and 10%; - Fat between 1 and 5%; - Ash between 1 and 2%; - Ph between 4 and 4.5; - Acidity between 4 and 12 mL 0.1N NaOH / 10 mL of product - Viscosity between 2500 and 10000 cPs. - low milk protein levels, less than 10% protein, when obtained from the PUFC, with Lactococcus spp. and Lactobacillus spp. 10.000.000 CFU / g and yeasts higher than 1,000,000 CFU / g, and the following physico-chemical composition: - Total solids between 10 and 15%; - Protein between 0.5 and 4%; - Fat between 0 and 1%; - Ash between 1 and 2%; - Ph between 4 and 4.5; - Acidity between 0.5 and 6 mL 0.1N NaOH / 10 mL of product - Viscosity between 2 and 1000 cPs.

Brief description of the figures

For an easier understanding of the invention, Figures 1 to 7 represent preferred embodiments of the invention which, however, are not intended to limit the object or scope of the present application.

Figure 1. Flowchart of the production process of liquid whey protein concentrates (CLPS) and inverse osmosis concentrate ultrafiltration (PUFC) permeate. 14

Figure 2. Process for obtaining CLPS and PUFC followed by the use of these products as the base raw material in the production of kefir-fermented dairy drinks, probiotic bacteria or the mixture of both.

Figure 3. Experimental data on the production of fermented dairy drinks with kefir grains, probiotic dairy bacteria and both based on CLPS and PUFC: Chemical composition of the fermented products based on CLPS (a) and PUFC (b) . k: kefir; p: probiotic; k + p: kef ir + probiotic; ST: total solids. A, B ... averages with different capital letters for each component, differ statistically (p < 0.05) between the product type, for each case of base raw material.

Figure 4. pH and titratable acidity (0.1 N NaOH / 10 mL product) of the fermented beverages during the fermentation and storage process, (a) and (c): CLPS; (b) and (d): PUFC; k = kefir; p = probiotic; k + p = kef ir + probiotic. A, B ... means with different capital letters differ statistically (p < 0.05) over time, for each case of base raw material.

Figure 5. Viscosity (cPs) of fermented beverages produced from CLPS (a) and PUFC (b); k = kefir; p = probiotic; k + p = kef ir + probiotic. A, B ... means with different capital letters differ statistically (p < 0.05) over time, for each case of base raw material.

Figure 6. Microbiological evolution of fermented beverages by kefir. (a): based on CLPS; (b): based on PUFC. 15

Figure 7. Microbiological evolution of fermented beverages produced from CLPS. (a): kefir with fresh CLPS; (b): kefir with thawed CLPS; (c): probiotic with fresh CLPS; (d): probiotic with thawed CLPS; (e): kefir + probiotic with fresh CLPS; (f): kefir + probiotic with thawed CLPS.

Description of Embodiments The present invention relates to the use of liquid whey protein concentrates (CLPS) and reverse osmosis concentrate ultrafiltration permeate (PUFC) in the production of dairy foods, in particular fermented dairy drinks. The CPLS is obtained by the concentration of whey, whose composition is presented in Table 1, by ultrafiltration (UF), thermal denaturation of the proteins of the obtained concentrate and their subsequent homogenization, in order to allow their isolated use in the manufacture of several dairy products, in particular fermented or acidified milk drinks, fully substituting milk. From the ultrafiltration process also results the whey permeate which is subsequently concentrated (PUFC). This product is very rich in lactose and mineral salts, and can also be used as a partial or integral substitute for milk for fermentation. The CLPS obtained by ultrafiltration contains a solids content which, depending on the volumetric concentration factor (FCV = 15 or 20), may be between 11.55% and 25.60%, the remaining components having a concentration according to referred to in Tables 1 and 2. 16

Table 1. Approximate composition of lactose and liquid whey protein concentrates after ultrafiltration of lactose.

Composition (%) Lactose Serum concentrate (FCV = 15) (a) (FCV = 20) (b) Total solids 5.25-6.6 11.55-20.6 13.8-25.6 Protein 0, 4-0.5 6.0-7.0 8.0-10.0 Fat 0.05-0.5 0.75-7.5 1.0-10.0 Lactose 4.2-4.8 4 , 2-4.8 4.2-4.8 Salts 0.6-0.8 0.6-0.8 0.6-0.8

Note: (a) FCV = 15; (b) FCV = 20

Table 2 - Average physical-chemical composition of the fermented CLPS.

Product Total solids (%) Protein (%) Fat (%) Ash (%) pH Acidity (D Viscosity (cPs) Fermented CLPS 15-20 6-10 1-5 1-2 4-5,9-9 2500- 10000 (1) - mL NaOH 0.1 N / 10 mL product The development of food products produced entirely from CLPS and from the PUFC is distinctive from other existing solutions.

In conventional processes of yoghurt production / fermented dairy products the protein matrix is based on the existing caseins in milk. In the case of the present embodiment, because the products are produced exclusively on a serum basis, the protein matrix that is formed results exclusively from the presence of whey proteins (especially beta-lactoglobulin and alpha-lactalbumin). The nutritional value may be considered to be similar to that of traditional curd, but the products obtained through this process have organoleptic characteristics clearly different from those of curd and approaching those of a common yogurt.

In addition, the use of a specific culture of kefir whose probiotic activity is widely documented, when associated or not, to commercial probiotic strains constitutes a remarkable nutritional value.

In addition to the added value provided by the increased nutritional value of the food products obtained, the use of the entire by-product of dairies, which causes a serious environmental problem with a national and international character, is another specificity of this achievement. In this context, the fact that technological processes with very high energy needs are not used, allows them to be implemented in small / medium-sized industrial units, without the use of large financial investments, as a way of simultaneously satisfying the legal requirements in environmental terms and valuation and diversification of its own products. With this technology, all the solid components of the serum can be reused and transformed into food products, resulting in only water. It is thus demonstrated that the great advantage of this process is undoubtedly the closed-loop perspective on the reuse of lactose. 18

Explanation of the processes for obtaining CLPS and PUFC and the processes for the production of fermented milk drinks: 1- Process of obtaining CLPS and PUFC The serum is filtered (it can also be skimmed) and concentrated at 50-55 ° C using an ultrafiltration (UF) equipment equipped with 10-20 kDa membranes (cutoff threshold) in discontinuous or continuous mode of operation. The volumetric concentration factor (FCV = feed volume / retention volume) applied may vary from 15 to 20, depending on the level of solids concentration desired in the CLPS. After concentration, the UF retentate (5-7% of the initial feed volume), with a solids concentration lying between the values given in Tables 1 (a or b) and 2, is subjected to a heat treatment at 85-95ø C, for at least 5 minutes, but preferably 20 minutes, in order to denature the proteins. The heating of the product may be carried out in a jacketed tank under moderate agitation and recirculation by means of a positive displacement pump, being maintained at that temperature for the necessary time and then cooled to 70 ° C before being homogenized at 50-100 bar . Preferably, the product may be heated to the desired temperature in tubular or scraped surface exchangers and maintained under moderate stirring and recirculated through a positive displacement pump before being cooled to 70øC. After this cooling is homogenized at 50-100 bar in a homogenizer to obtain aggregates of 19 particles with diameters of less than 10 and m. The flow diagram of the CLPS production process is shown in Figure 1. The UF permeate (93-95% of the initial volume of serum) and the composition referred to in Tables 3 and 4 is concentrated by reverse osmosis to about half or 1/3 of its initial volume. This permeate after being concentrated to a total solids content of 9.71% and 16.97%, considering FCV equal to 2 and 3, respectively (Tables 3 and 4), can be subjected to a fermentation process with grains of kefir (CIDCA AGK1) or other microbial cultures including commercial probiotic strains under the most suitable fermentation conditions for each selected strain.

Table 3. Approximate permeate composition of serum UF and permeate concentrates.

(A) (FCV = 3) (b) Total solids 4,85-5,65 9,71-11,31 14,56-16,97 Protein (%) Permeado of UF Permeado concentrate OI (FCV = 2) 0.05 0.1 0.15 Fat 0.005 0.01 0.015 Lactose 4.2-4.8 8.4-9.6 12.6-14.4 Salts 0.6-0.8 1.2-1 , 6.8-2.4

Note: (a) FCV = 2; (b) FCV = 3

Table 4 - Average physical-chemical composition of fermented PUFC

Product Total solids (%) Protein (%) Fat (%) Ash (%) pH Acidity (D Viscosity (cPs) Fermented PUFC 10-15 0.5-4 0-1 1-2 4-5,9 -6 2-1000 20 (1) - ml NaOH 0.1 N / 10 ml product 2-Process for obtaining fermented dairy products The CLPS produced or the PUFC can be immediately integrated into the manufacturing processes of: - Liquid fermented milk drinks (high viscosity) or solid fermented dairy products (whole use of CLPS, alone or in whole or in skimmed milk powder and other ingredients, in particular fruit pulp or flavor, sugar and / or other flavorings and / or fruit preparations );

Fermented or acidified liquid milk drinks (with low viscosity) (by the use of PUFC, added or not of other ingredients, namely milk powder, flavorings and / or fruit preparations).

Process for the production of liquid (viscous) fermented dairy drinks and fermented dairy products (solids) based on CLPS

To the CLPS obtained (Figure 2), whole or skim milk powder at a concentration of approximately 5-10% (w / v) can be added, the mixture being thermally treated at 90øC for 20 minutes, cooled to 70øC and homogenized at 100 bar. The base mix for the production of fermented milk drinks may contain other ingredients, such as sugar, flavorings or fruit preparations. It is then cooled to the appropriate temperature and subjected to a tank fermentation process by kefir grains (CIDCA AGK1), alone or in combination with 21 selected lactic bacteria which may include commercial probiotic strains of Lactobacillus acidophillus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus plantarum or mixtures of these strains in varying proportions to pH about 4.5 and gelling. Immediately after the desired pH is reached the product is transferred to a cooling tunnel in order to minimize the cooling time until the temperature reaches below 20Â ° C, preferably the temperature of 10Â ° C (over less than 1 hour ). It must then be stored in a chill chamber at a temperature not exceeding 4 ° C.

2.2. Process for the production of PUFC-based liquid fermented or acidified milk drinks The ultrafiltration permeate (Figures 1 and 2) is concentrated by reverse osmosis and added or not to other ingredients, namely powdered milk, sugar, flavorings or fruits. It can then be homogenized at 100 bar and heat treated at 75 ° C for 30 seconds (homogenization is particularly justified where powdered milk is optionally added). After cooling to the appropriate temperature, it is subjected to a tank fermentation process by kefir grains (CIDCA AGK1), alone or in combination with selected lactic bacteria which may include commercial probiotic strains of Lactobacillus acidophillus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus plantarum or mixtures of these strains in varying proportions. After reaching the desired pH the fermentation or acidification are stopped by cooling to 4 ° C and the product is packed. 22

Experimental data

Example of experimental data on the production of fermented dairy drinks with kefir grains, probiotic dairy bacteria and both based on CLPS and PUFC.

Table 5. Chemical composition of the fermented products based on CLPS and PUFC. k: kefir; p: probiotic; k + p: kefir + probiotic; ST: total solids.

ST products (%) Protein (%) Fat (%) Ash (%) Mean CLPS + Mean DP + Mean DP + Mean DP + DP k 15.59 0.02 6.90 90.4 2.30 0.10 1 , 36 0.22 P 16.77 0.35 6.71 0.31 1.40 0.001 1.56 0.12 k + p 16.70 0.004 6.37 0.09 1.67 0, 12 1, 600.05 Mean PUFC + Mean DP + Mean DP + Mean DP + DP k 11.52 0.19 0.50 0.03 0.40 0.10 10.116 0.01 P 10.84 0 , 05 0.78-0.07 0.37-0.06 1.07 0.01 k + p 11.27 0.07 0.62 0.07 0.37 0.06 1.12 0.01

Table 6. pH and titratable acidity AT (0.1 N NaOH / 10 mL product) of the fermented beverages based on CPLS and PUFC during fermentation and storage. k = kefir; p = probiotic; k + p = kefir + probiotic.

CLPS products PUK pH k P k + pk P k + p Mean time (h) mean ± SD mean ± SD mean + mean SD + mean SD + mean SD + SD 0 5.50 0.10 5.37 0.12 5, 37 0.06 4.80 0.05 4.80 0.04 4.79 0.01 24 4.47 0.06 4.47 0.06 4.33 0.06 4.43 0.06 4.70 0.10 4.13 0.12 168 4.25 0.05 4.15 0.05 4.19 0.01 4.38 0.03 4.43 0.06 4.10 0.10 Products CLPS PUFC AT k P k + pk P k + p Mean (h) Mean ± SD Mean ± SD Mean ± SD Mean ± SD Mean ± SD Mean ± SD 0 4.38 0.14 4.45 0.07 4.41 0.09 0.81 0.04 0.81 0.04 0.81 0.04 24 8.87 0.15 7.65 0.20 9.61 0.38 3.58 0.52 3.93 0.16 3 , 29 0.04 168 9.30 0.17 8.56 0.10 9.63 0.05 4.26 0.02 3.29 0.04 3.28 0.06 23

Table 7. Viscosity (cPs) of the fermented beverages produced from CLPS and PUFC over time.

CLPS

Time (h) mean kefir ± SD average probiotic ± DP kefir + average probiotic ± SD 24 3013.33 15.28 3650.00 217.03 3443.33 20.82 168 1816.67 15.28 3236.67 15.28 3153.33 5.77

PUFC kefir probiotic kefir + probiotic Time (h) mean ± SD mean ± SD mean ± SD 24 2.30 0.01 2.43 0.01 2.35 0.01 168 3.07 0.01 2.95 0, 01 2.82 0.00

Table 8. Evolution in logistic microbiological terms (CFU / mL) of kefir-fermented beverages based on CLPS and PUFC.

CLPS

Lactococcus spp. Lactobacillus spp. Yeasts Time (days) mean ± SD mean ± SD mean ± SD 0 5.27 0.05 5.13 0.47 4.72 1.24 12 7.61 0.39 7.60 5.58 0.15 24 8.34 0.555 6, 98 0.46 6, 66 0.15 48 8.75 0.38 8.78 0.44 7.54 0.56 168 7.96 0, 23 6, 89 0.49 6, 42 0.32 PUFC Lactococcus spp Lactobacillus spp Yeasts Time (days) mean ± SD mean ± SD mean ± SD 0 4.15 0.121 4.74 0.30 5.18 0, 89 12 6, 62 0, 15 7.08 0, 50 6, 82 0.47 24 7.50 0.26 7, 66 0.15 5.82 0.39 48 8.54 0.62 8.91 0 , 20 8.00 0.14 168 7.75 0.17 7.73 0.27 6.28 0.20 24

Table 9. Microbiological evolution of logs (CFU / mL) of fermented beverages produced from fresh and thawed CLPS. k = kefir; p = probiotic; k + p = kefir + probiotic. kefir CLPS fresh CLPS thawed T (d)

Lactococcus spp mean ± SD

Lactobacillus spp mean ± SD

Yeast mean ± SD

Lactococcus spp mean ± SD

Lactobacillus spp mean + DP

Yeasts average ± SD 0 1 7 14 5.27 0.05 7.80 0.00 9.38 0.08 9.39 0.08 5.27 0.058.01 0.10 8.34 0.14 5.13 0.47 8 , 17 0.03 7.79 0.73 7.82 0.61 4.72 1.24 5.74 0.37 7.27 0.89 6.56 0.59 5.27 0.05 8.25 0.34 7.30 0.00 7.00 0.00 5.13 0.47 8.68 0.18 7.74 0.00 7.50 0.00 4.72 1.24 6.78 0, 39 6.34 0.006.88 0.10 probiotic CLPS fresh CLPS thawed T (d) Lactococcus spp mean ± SD Lactobacillus spp mean ± SD - Lactococcus spp mean ± SD Lactobacillus spp mean + DP -0 5.27 0.05 5, 13 0.47 5, 27 0.05 5.13 0.47 1 7.90 0.10 8.21 0.15 7.43 0.15 8.19 0.11 7 8.68 0.65 8, 85 0.69 8.04 0.06 8.58 0.12 14 7.23 0.18 7.73 0.40 7.00 1.20 7.43 1.38 kefir + probiotic Fresh CLPS CLPS thawed T ( (d)

Lactococcus spp mean ± SD

Lactobacillus spp mean + DP

Yeast mean ± SD

Lactococcus spp mean + DP

Lactobacillus spp mean ± SD

Yeasts average ± SD 0 1 7 14 5.13 0.47 7.97 1.21 8.71 0.43 8.13 0.60 4.72 1.24 6.37 0.91 7.20 0.00 7.00 0 , 00 5.27 0.05 8.50 0.22 8.55 0.12 8.42 0.10 5.13 0.47 8.56 0.16 8.22 0.11 8.23 0.10 4.72 1.24 6.50 0.32 5.87 0.86 6.92 0.37

Lisbon, June 20, 2014 25

Claims (12)

A process for the production of dairy products comprising the following steps: - ultrafiltration of the lactose, from which the liquid whey protein concentrate (CLPS) and the permeate result; - CLPS thermal treatment, subsequent homogenization and cooling of the CLPS, and - concentration of the inverse osmosis ultrafiltration permeate and obtaining the concentrated ultrafiltration permeate (PUFC), - inoculation and fermentation of CLPS and PUFC with kefir, lactic acid bacteria and / or their mixtures; cooling to a temperature below 20 ° C for a period of less than 1 hour. Process for the production of dairy products according to the preceding claim, characterized in that the heat treatment of the CLPS is carried out at a temperature between 85-95 ° C for at least 5 minutes and cooling to the temperature of 70 ° C. Process for the production of dairy products according to any one of the preceding claims, characterized in that the homogenization of the CLPS is carried out under a pressure of 50 to 100 bar. 1 Process for producing dairy products according to any one of the preceding claims, characterized in that the ingredients selected from the group consisting of: milk powder, sugar, fruit flavors or preparations are added to the CLPS or the PUFC and the adjuvants are selected of thickening gums, whole or skimmed milk powder. Process for the production of dairy products according to the preceding claim, characterized in that the mixture of PUFC and added ingredients is homogenised at 50 bar and heated to a temperature of 75 ° C for a period of 30 seconds. Process for the production of dairy products according to any one of the preceding claims, characterized in that the lactic acid bacteria are selected from a group comprising a specific culture of kefir grains (CIDCA AGK1), alone or in combination with lactic acid bacteria such as : Lactobacillus acidophillus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus plantarum or mixtures of these strains. Process for the production of dairy products according to any one of the preceding claims, characterized in that the fermentation takes place until reaching a pH of 4.5. Process for the production of dairy products according to any one of the preceding claims, characterized in that the rapid cooling is carried out either by means of a cooling tunnel or in a tubular exchanger. Dairy products obtained by the process described in claims 1 to 8, characterized by having a protein matrix comprising 90% to 100% whey proteins, when obtained from the CPLS. Dairy products according to the preceding claim, characterized in that they have Lactococcus spp. and Lactobacillus spp. more than 10,000. 000 CFU / g and yeasts greater than 1,000,000 CFU / g, and the following physico-chemical composition: - Total solids between 15 and 20%; - Protein between 6 and 10%; - Fat between 1 and 5%; - Ash between 1 and 2%; - Ph between 4 and 4.5; - Acidity between 4 and 12 mL 0.1N NaOH / 10 mL of product - Viscosity between 2500 and 10000 cPs. Dairy products obtained by the process described in claims 1-8, characterized in that they contain low milk protein levels of less than 10% protein when obtained from the PUFC. Dairy products according to the preceding claim, characterized in that they have Lactococcus spp. and Lactobacillus spp. more than 10,000. 000 CFU / g and yeasts greater than 1,000,000 CFU / g, and the following physico-chemical composition: - Total solids between 10 and 15%; 3 - Protein between 0.5 and 4%; - Fat between 0 and 1%; - Ash between 1 and 2%; - Ph between 4 and 4.5; - Acidity between 0.5 and 6 mL 0.1N NaOH / 10 mL of product - Viscosity between 2 and 1000 cPs. Lisbon, June 20, 2014 4