LU501362B1 - Yogurt and process for preparing a yogurt - Google Patents

Abstract

The invention relates to a yogurt, in particular Turkish yogurt-type yogurt, obtained from a composition comprising, relative to the weight of the composition: - between 65.10 and 65.99% by weight, preferably between 65.65 and 65.95% by weight, more preferably 65.80% by weight, of milk, - between 33.90 and 34.90% by weight, preferably between 33.95 and 34.25% by weight, more preferably 34.10% by weight, of cream, - between 0.08 and 0.12% by weight, preferably between 0.09 and 0.11% by weight, more preferably 0.10 % by weight of lactic ferments, the yogurt comprising, relative to its weight, from 9.60 to 10.40% by weight, preferably 10% by weight, of fat. The invention also relates to a process for the preparation of such a yogurt.

Description

YOGURT AND METHOD FOR PREPARING A YOGURT

Technical area

The present invention generally relates to a fermented dairy product and a process for manufacturing such a dairy product, and in particular a yoghurt and a process for manufacturing a yoghurt. More particularly, the invention relates to a Turkish yoghurt comprising 10% by weight of fat and its method of manufacture.

State of the art

[0002] A yogurt is obtained by fermentation of milk, using a combination of lactic acid bacteria of the strains Streptococcus thermophilus and Lactobacillus bulgaricus, and is in the form of a gel containing at least 10 million live bacterial strains per gram of finished product. Yogurt is a fresh product with complex organoleptic properties, and various processes have been proposed to maintain or improve these organoleptic qualities.

[0003] In order to improve the texture obtained, and to approximate the texture of a traditional Turkish yoghurt, it has been proposed to increase the supply of dry matter, for example in the form of protein powder, or more simply in the form of milk powder. However, increasing the amount of dry matter in yogurt can also limit the growth of bacterial cultures, and therefore prevent the classification of the resulting product as yogurt.

Object of the invention

An object of the present invention is therefore to provide a yoghurt of the Turkish yoghurt type having both a taste and a texture substantially identical to those of a traditional Turkish yoghurt, in particular a short and firm, smooth and non-grainy, and helps preserve the yoghurt classification.

General description of the invention

The invention relates, in a first aspect, to a yogurt, in particular a Turkish yogurt-type yogurt, obtained from a composition comprising, relative to the weight of the composition:

- between 65.10 and 65.99% by weight, preferably between 65.65 and 65.95% by weight, more preferably 65.80% by weight, of milk, - between 33.90 and 34.90 % by weight, preferably between 33.95 and 34.25% by weight, more preferably 34.10% by weight, of cream, - between 0.08 and 0.12% by weight, preferably between 0, 09 and 0.11% by weight, more preferably 0.10% by weight, of lactic ferments, the yogurt comprising, based on its weight, from 9.60 to 10.40% by weight, preferably 10% in weight of fat.

[0006] Surprisingly, the inventors have discovered that the preparation of a yogurt comprising only the ingredients listed above in these concentration ranges makes it possible to obtain a yogurt having a taste and a texture similar to those of a traditional turkish yogurt. In particular, such a percentage of fat in the yogurt advantageously makes it possible to obtain the desired texture, and defines its quality, in particular its organoleptic properties.

According to the invention, the cream represents between 33.90 and 34.90% by weight of the composition, relative to its total weight. Such a quantity of cream advantageously makes it possible to obtain a yoghurt having a smooth and non-grainy texture typical of a traditional Turkish yoghurt. If the composition includes less cream, the texture obtained will not be smooth enough compared to a traditional yogurt. On the contrary, if the composition comprises more cream, the texture obtained will be too firm and/or too sticky.

Advantageously, the milk used in the composition from which the yoghurt according to the invention is obtained can be whole milk, semi-skimmed milk or skimmed milk. According to a preferred embodiment, the milk is skimmed milk.

The cream used in the composition from which the yogurt according to the invention is obtained is generally cream comprising between 20 and 50% fat, preferably between 25 and 35%. According to a preferred embodiment, the cream comprises approximately 30% fat.

Preferably, the lactic ferments comprise lactic ferments of the Streptococcus thermophilus and/or Lactobacillus bulgaricus type, so as to be able to obtain the yoghurt name for the finished product obtained from the composition according to the invention.

[0011] According to a particularly preferred embodiment, the milk is skimmed milk and the cream is a cream with 30% fat so as to allow the production of a yogurt comprising approximately 10% fat with respect to its weight, and having a smooth texture, not grainy, and free of syneresis (that is to say the separation of the water contained in the milk from the rest of the yoghurt) typical of a traditional Turkish yoghurt.

[0012] According to certain embodiments, the yogurt obtained has a pH of between 4.40 and 4.80, preferably the yogurt has a pH of 4.60. Such a pH is obtained by lactic fermentation of milk using lactic ferments and makes it possible to neutralize the decomposition of milk, in particular of milk proteins, and thus to improve the shelf life of the yoghurt obtained. Advantageously, such a pH also makes it possible to obtain a yoghurt having a fairly present acidity, and a taste typical of that of a traditional Turkish yoghurt.

In a second aspect, the invention also relates to a process for preparing a yogurt as described above. The method comprises the following steps: a) weighing the milk, the cream and the lactic ferments, the ingredients being weighed separately; b) mixing milk and cream; c) heating of the milk and cream mixture to a temperature T1 for a time t1; d) heat treatment at a temperature T3 for a time t3 of the heated milk and cream mixture: e) maturation at a temperature T4 for a time t4 of the heat-treated milk and cream mixture; f) cooling to a temperature TS of the matured milk and cream mixture, then inoculation of the cooled matured milk and cream mixture using the lactic ferments weighed in step a); g) conditioning of the inoculated mixture in line at a temperature T6;

h) maturation at a temperature T7 of the conditioned inoculated mixture until a pH of between 4.7 and 4.8, preferably a pH of 4.75, is obtained and yoghurt is obtained.

[0014] Surprisingly, the inventors have discovered that a process for preparing a yoghurt having milk, cream and lactic ferments as the only ingredients, makes it possible to obtain the desired organoleptic properties for a Turkish yoghurt , by implementing holding steps at different temperatures (i.e. ripening steps). In particular, such a process makes it possible to obtain the desired short and firm, smooth and non-grainy texture, typical of a traditional Turkish yogurt.

[0015] The different stages of maintaining at different temperatures also advantageously makes it possible to refine the taste of the yoghurt and to obtain the desired taste.

Advantageously, the heating of the milk and cream mixture in step c) generally has a duration t1 of between 3 and 5 hours, preferably a duration of 4 hours.

As a variant or in addition, the heating of the milk and cream mixture in step c) is generally carried out at a temperature T1 of between 5 and 10°C, preferably at a temperature of 8°C. Such a duration and such a temperature during the reheating step advantageously make it possible to obtain a yoghurt having the desired quality, in particular in terms of taste and texture.

According to certain variants, the method also comprises the following step: i) cooling of the milk and cream mixture to a temperature T2 and storage for a period t2;

step i) being carried out between steps b) and c).

According to the same or other embodiments, the cooling in step i) is carried out at a temperature T2 of between 0 and 5°C, preferably at a temperature T2 of 2°C. Advantageously, the storage in step i) has a duration t2 of between 1 and 8 hours, preferably between 1 and 3 hours, particularly preferably 2 hours.

According to the same or other embodiments, the maturation in step e) has a duration t4 of between 30 and 60 minutes, preferably a duration t4 of 40 minutes. Advantageously, the maturation in step e) is carried out at a temperature T4 of between 15 and 25°C, preferably at a temperature T4 of °C. Such a duration and such a temperature during the maturation step advantageously make it possible to obtain a yoghurt having the desired quality, in particular in terms of taste and texture.

[0020] According to the same or other embodiments, the cooling in step f) is generally carried out at a temperature T5 of between 0 and 5° C., preferably at a temperature T5 of 2° C.

According to the same or other embodiments, the conditioning in step g) is carried out at a temperature T6 of between 42 and 50° C., preferably at a temperature T6 of 46° C. Such a temperature T6 allows an optimal impact on the development of lactic ferments in the yogurt, and therefore the texture and taste of the finished product obtained, advantageously very close to those of a traditional yogurt.

According to the same or other embodiments, the maturation in step h) is carried out at a temperature T7 of between 40 and 46° C., preferably at a temperature T7 of 43° C. Such a temperature T7 allows an optimal impact on the development of the lactic ferments in the yogurt, and therefore the texture and the taste of the finished product obtained, advantageously very close to those of a traditional yogurt.

According to a particularly preferred variant of the process according to the invention, the milk and cream mixture is prepared from skimmed milk and cream with 30% fat, cooling in step i) is done at 2 ° C and the resulting mixture is kept (i.e. stored) for 2 hours, then it is reheated in step j) at 8°C for 4 hours, before maturing for 40 minutes at 20°C (step e)), the cooling in step f) is carried out at 2°C, the conditioning in step g) is carried out at 46°C and the maturation in step h) is carried out at 43°C.

Such a combination of temperature and duration conditions for all of the steps involved in the preparation process according to the invention advantageously makes it possible to obtain a yogurt that optimally possesses all of the desired properties, namely a short and firm texture, smooth and not grainy, a present acidity, an absence of syneresis, as well as a typical taste, characteristics of a traditional Turkish yoghurt.

The method according to the invention comprises a step d) of heat treatment. Such a heat treatment allows long-term preservation of the milk and cream mixture by destroying the pathogenic agents potentially present in the milk and/or the cream, such as bacteria. Such a heat treatment also has the advantage of having a negligible influence on the structure of the proteins present in the milk and/or the cream, and therefore a negligible influence on the texture of the final product, that is to say on the texture of the yogurt obtained using the process according to the invention.

According to the same or other embodiments, the heat treatment in step d) generally has a duration t3 of between 3 and 7 min, preferably a duration t3 of 5 min. Advantageously, the heat treatment in step d) is carried out at a temperature T3 of between 90 and 95°C, preferably at a temperature T3 of 93°C.

[0027] According to the same or other embodiments, the heat treatment step d) can also comprise a sub-step for homogenizing the milk and cream mixture. The homogenization is preferably carried out directly before the application of the temperature T3 for a duration t3. Preferably, the homogenization is carried out using a two-step homogenization process, in which the milk and cream mixture is subjected to a pressure of between 150 and 250 bar, preferably 200 bar, in a first stage and at a pressure of between 15 and 45 bars, preferably 30 bars, in a second stage.

According to certain embodiments, the process for preparing a yoghurt according to the invention also comprises the following step: j) cooling to a temperature T8 of between 0 and 5° C., preferably to a temperature T8 of 2°C, yogurt obtained in step h).

Advantageously, such a cooling step carried out after the maturation makes it possible to stop the maturation of the product obtained, and therefore to stop the evolution of the pH. Stopping the maturation by the cooling step carried out at the temperature T8 is also advantageous for the preservation of the yoghurt obtained, and in particular allows its preservation for a longer period.

[0030] All the embodiments cited above, both for yoghurt and for the process for preparing said yoghurt, can be combined subject to their technical feasibility.

Detailed description with examples

Various yogurts of Turkish yogurt type were produced from the compositions of Table 1. The amounts are expressed in% by weight relative to the total weight of the composition. The compositions according to the invention are not limited to the example provided in this table. [Table 1]

Ingredient Composition Example Example according to the invention Comparative 1 Comparative 2

30% cream 34.10% 25% cream 40% fat cream fat 41.0% 25.6%

Lactic ferments 0.10% 0.10% 0.10% (Streptococcus thermophilus and

Lactobacillus bulgaricus)

Each of the yogurts was prepared using the following process, the preparation steps being carried out in this order:

Step a) Weighing the ingredients, the ingredients being weighed separately;

[0034] Step b) Mixing the milk and the cream to form a milk and cream mixture;

Step i) Cooling to 2° C. and storage for 2 h;

Step c) Reheating at 8° C. for 4 hours;

Step d) Heat treatment (93° C. for 5 min, homogenization 200/30 bar);

Step e) Maturation at 20° C. for 40 min in a storage tank;

Step f) Cooling to 2° C. and inoculation of the milk and cream mixture comprising the milk powder with the lactic ferments;

[0040] Step g) Conditioning of the inoculated mixture with reheating in line at 46° C.;

Step h) Maturation at 43° C. until a pH of 4.75 is obtained for the milk and cream mixture inoculated with the lactic ferments to obtain the Turkish yoghurt.

The three Turkish yoghurts obtained were tasted blind in order to determine their texture and their taste. The evaluation showed that the yogurt obtained from a composition according to the invention has a taste and a texture similar to the taste and texture of traditional Turkish yogurts. The yogurt obtained from comparative composition 1 has a less creamy texture and a taste that is not pronounced enough compared to a traditional yogurt. On the contrary, the yoghurt obtained from comparative composition 2 has an excessively heavy/creamy texture, while its taste is too pronounced and not acid enough.

Claims (16)

Claims 1. Yoghurt, in particular Turkish yoghurt type yoghurt, obtained from a composition comprising, relative to the weight of the composition: - between 65.10 and 65.99% by weight, preferably between 65.65 and 65.95% by weight, more preferably 65.80% by weight, of milk, - between 33.90 and 34.90% by weight, preferably between 33.95 and 34.25% by weight, of more preferably 34.10% by weight, of cream, - between 0.08 and 0.12% by weight, preferably between 0.09 and 0.11% by weight, more preferably 0.10% by weight , lactic ferments, the yogurt comprising, relative to its weight, from 9.60 to 10.40% by weight, preferably 10% by weight of fat. 2. Yoghurt according to claim 1, in which the milk is whole milk, skimmed milk or semi-skimmed milk, preferably the milk is skimmed milk. 3. Yogurt according to claim 1 or 2, wherein the cream comprises between and 50% fat, preferably between 25 and 35%, more preferably the cream comprises 30% fat. 4. Yoghurt according to any one of the preceding claims, in which the lactic ferments comprise Streptococcus thermophilus and/or Lactobacillus bulgaricus. 5. Yogurt according to any one of the preceding claims, the yogurt having a pH of between 4.40 and 4.80, preferably the yogurt has a pH of 4.60. 6. Process for preparing a yogurt according to any one of the preceding claims, the process comprising the following steps: a) weighing the milk, the cream and the lactic ferments, the ingredients being weighed separately; b) mixing milk and cream; c) heating of the milk and cream mixture to a temperature T1 for a time t1; d) heat treatment at a temperature T3 for a time t3 of the heated milk and cream mixture; e) maturation at a temperature T4 for a time t4 of the heat-treated milk and cream mixture; f) cooling to a temperature T5 of the matured milk and cream mixture, then inoculation of the cooled matured milk and cream mixture using the lactic ferments weighed in step a); g) conditioning of the inoculated mixture in line at a temperature T6; h) maturation at a temperature T7 of the conditioned inoculated mixture until a pH of between 4.7 and 4.8, preferably a pH of 4.75, is obtained and yoghurt is obtained. 7. Process according to claim 6, in which the heating of the milk and cream mixture in step c) has a duration t1 of between 3 and 5 hours, preferably a duration of 4 hours, and/or in which the heating of the mixture milk and cream in step c) is carried out at a temperature T1 of between 5 and 10°C, preferably at a temperature of 8°C. 8. Method according to claim 6 or 7, further comprising the following step: i) cooling of the milk and cream mixture to a temperature T2 and storage for a period t2; step i) being carried out between steps b) and c). 9. Process according to claim 8, in which the cooling in step i) is carried out at a temperature T2 of between 0 and 5°C, preferably at a temperature T2 of 2°C and/or in which the storage has step i) has a duration t2 of between 1 and 8 h, preferably of between 1 and 3 h, particularly preferably of 2 h. 10.Procédé according to any one of claims 6 to 9, wherein the reheating in step c) has a duration t1 of between 2 and 6 h, preferably a duration t1 of 4 h, and / or wherein the reheating in step c) is carried out at a temperature T1 of between 5 and 10°C, preferably at a temperature T1 of 8°C. 11. Process according to any one of claims 6 to 10, in which the heat treatment in step d) has a duration t3 of between 3 and 7 min, preferably a duration t3 of 5 min, and/or in which the heat treatment in step d) is carried out at a temperature T3 of between 90 and 95°C, preferably at a temperature T3 of 93°C. 12. Process according to any one of claims 6 to 11, in which the maturation in step e) has a duration t4 of between 30 and 60 minutes, preferably a duration t4 of 40 minutes, and/or in which the ripening at step e) is carried out at a temperature T4 of between 15 and 25°C, preferably at a temperature T4 of 20°C. 13. Process according to any one of claims 6 to 12, in which the cooling in step f) is carried out at a temperature T5 of between 0 and 5°C, preferably at a temperature T5 of 2°C and/ or wherein the conditioning in step g) is carried out at a temperature T6 of between 42 and 50°C, preferably at a temperature T6 of 46°C. 14. Process according to any one of claims 6 to 13, in which the maturation in step h) is carried out at a temperature T7 of between 40 and 46°C, preferably at a temperature T7 of 43°C. 15. Process according to any one of claims 6 to 14, in which step d) of heat treatment comprises a sub-step of homogenization before application of the temperature T3, the homogenization preferably being carried out according to a homogenization process in two stages, in which the milk and cream mixture is subjected to a pressure of between 150 and 250 bars, preferably 200 bars, in a first stage and to a pressure of between 15 and 45 bars, preferably 30 bars, in a second step. 16. Process according to any one of claims 6 to 15, further comprising the following step: j) cooling the yogurt obtained in step h) to a temperature T8 of between 0 and 5°C, preferably at a temperature T8 of 2°C.