Yoghourt and preparation method thereof

Abstract

The invention provides yoghurt and a preparation method thereof, the pH value of the yoghurt is 4.7-6.5, the yoghurt comprises a yoghurt base material and an additive, the additive contains alkaline buffer salt, and the alkaline buffer salt comprises at least one of sodium bicarbonate, disodium hydrogen phosphate and sodium acetate. The yoghourt disclosed by the invention has the advantages of being low in sour taste, high in nutritional value, long in shelf life, wide in applicable crowd and the like.

Description

Technical Field

[0001] The present application relates to the field of food, and in particular to yogurt and a method for preparing the same. Background Art

[0002] As consumers' health awareness improves and their requirements for food quality increase, consumers' demand for natural, healthy and delicious yogurt is growing. Although traditional yogurt is nutritious and has a unique taste, its high acidity is not suitable for all people, especially children, the elderly and people with sensitive gastrointestinal tracts. In addition, in certain cultural backgrounds, people prefer to drink products with mild taste. Therefore, developing a "non-acid yogurt" that retains the original nutritional value of milk and reduces acidity has become an important direction to meet this part of the market demand. Summary of the invention

[0003] The present application aims to solve the technical problems existing in the prior art at least to a certain extent. To this end, the present application proposes a yogurt and a preparation method thereof, wherein the yogurt contains a yogurt base and an additive containing an alkaline buffer salt, and has the advantages of low sourness, high nutritional value, long shelf life and a wide range of applicable people.

[0004] It should be noted that this application is based on the inventor's discovery and understanding of the following facts and problems: During the fermentation process, yogurt produces acidic substances such as lactic acid, which makes its acidity higher. Usually, the pH value of yogurt does not exceed 4.5. The inventor found that when the pH value of yogurt reaches 4.7~6.5, the overall taste of yogurt is mild and the sourness is low. In order to obtain yogurt that meets the relatively high pH value mentioned above, if alkaline buffer salts are added before fermentation and fermented together with the yogurt base raw materials, a large amount of alkaline buffer salts need to be added to neutralize the acid produced by fermentation, and too much alkaline buffer salts will cause the existing fermentation agents to fail to ferment normally, resulting in fermentation failure, and thus the product characteristics that yogurt must have, such as the required viscous texture, cannot be obtained. However, in order to meet the normal fermentation and acid production of the fermentation agent, the alkaline buffer salts added are difficult to meet the final pH value requirements of the yogurt product. Therefore, it is impossible to obtain the expected product by adding alkaline buffer salts before fermentation. Further, after in-depth research, the inventor tried to obtain yogurt that meets the above pH requirements by adding alkaline buffer salts to the fermented yogurt base. However, if alkaline buffer salts are directly mixed with yogurt base to neutralize acidic substances, although the acidity can be reduced, this practice will destroy the overall taste of the product. In addition, commonly used alkaline buffer salts such as sodium bicarbonate cannot be pre-heated and sterilized because high temperatures will cause them to undergo chemical reactions and be lost. If unsterilized alkaline buffer salts are added to yogurt, the yogurt will quickly spoil, resulting in a significant shortening of the shelf life.

[0005] In view of this, the inventor adds alkaline buffer salts to the additives, which can not only effectively neutralize the acidic substances in the yogurt base, reduce the acidity of the yogurt, but also the introduction of the additives adds taste and nutritional value to the yogurt. At the same time, the alkaline buffer salts are placed in the additives, and can be sterilized together with the additive raw materials to avoid the loss caused by the decomposition of the alkaline buffer salts alone. However, since the alkaline buffer salts are added to the additives, the additives are alkaline, which requires higher sterilization conditions for the additives and requires high temperature sterilization, but too high a temperature will destroy the texture and taste of the additives. Therefore, the inventor takes into account the sterilization effect and texture and taste and optimizes the screening of the optimal sterilization temperature. At the same time, due to the large number of existing yogurt starter types, based on the characteristics of the yogurt of the present application, the starter needs to take into account both fermentation and acid production so that the yogurt has its necessary characteristics, and has the characteristics of low acid production rate, low acid production, and slow growth of acidity during the shelf life. Based on this requirement, the starter is optimized and screened. The result is a yogurt with low sourness, high nutritional value, long shelf life and a wide range of applicability.

[0006] To this end, in one aspect of the present application, the present application proposes a yogurt. According to an embodiment of the present application, the pH value of the yogurt is 4.7-6.5, and the yogurt includes: a yogurt base and an additive, the additive contains an alkaline buffer salt, and the alkaline buffer salt includes at least one of sodium bicarbonate, disodium hydrogen phosphate and sodium acetate; the raw materials of the yogurt base include a fermentation agent, and the fermentation agent includes at least one of a fermentation agent YO-PROX 600M, a fermentation agent Cremoso1.0, a fermentation agent PIONEER-02, a fermentation agent YoFlex®mild 1.0 and a fermentation agent YoFlex®Premium 1.0; the preparation method of the additive includes a sterilization treatment, and the temperature of the sterilization treatment is 140°C-150°C.

[0007] The yogurt according to the present application contains a yogurt base and an additive containing alkaline buffer salts, which can not only effectively neutralize the acidic substances in the yogurt base, reduce the acidity of the yogurt, make it mild in taste, and be suitable for a wide range of people. In addition, the alkaline buffer salts are placed in the additives, and can be sterilized together with the additive raw materials to avoid losses caused by decomposition of the alkaline buffer salts when sterilized alone. In addition, the introduction of the additives adds taste and nutritional value to the yogurt.

[0008] Since alkaline buffer salts are added to the additive, the additive is alkaline, which requires high sterilization conditions for the additive, and requires high temperature sterilization, but too high a temperature will destroy the texture and taste of the additive. Therefore, the inventors optimized and selected the above-mentioned preferred sterilization temperature taking into account both the sterilization effect and the texture and taste.

[0009] Since there are many types of existing yogurt starter cultures, based on the characteristics of the yogurt in this application, the starter culture needs to be able to ferment and produce acid so that the yogurt has its necessary characteristics, and also have the characteristics of low acid production rate, low acid production, and slow increase in acidity during the shelf life. Based on this requirement, the starter culture was optimized and screened to obtain the above-mentioned preferred starter culture type.

[0010] The result is a yogurt with low sourness, high nutritional value, long shelf life and a wide range of applicability.

[0011] According to the embodiments of the present application, the above yogurt may also have the following additional technical features: According to an embodiment of the present application, the alkaline buffer salt includes sodium bicarbonate.

[0012] According to an embodiment of the present application, the additive includes jam and / or cereal products.

[0013] According to an embodiment of the present application, based on the total mass of the additive, the content of the alkaline buffer salt is 0.05‰~0.4‰.

[0014] According to an embodiment of the present application, the sterilization treatment time is 4 min to 6 min.

[0015] According to the embodiment of the present application, based on the total mass of the yogurt base, the amount of the additive added is 5% to 10%. According to an embodiment of the present application, the raw materials of the yogurt base include at least one of raw cow's milk and reconstituted milk and at least one of the following: a sweetener and a stabilizer.

[0016] According to an embodiment of the present application, the raw materials of the jam include sugar and fruit juice.

[0017] In another aspect of the present application, the present application proposes a method for preparing the aforementioned yogurt. According to an embodiment of the present application, the method comprises: mixing the yogurt base and an additive to obtain the yogurt, and the preparation method of the jam comprises sterilization treatment, and the temperature of the sterilization treatment is 140°C to 150°C.

[0018] According to an embodiment of the present application, the method for preparing the yogurt base comprises: fermenting a starter with a pretreated yogurt base raw material, and when the fermentation liquid reaches a predetermined acidity, demulsifying the obtained fermentation liquid to obtain the yogurt base.

[0019] According to an embodiment of the present application, the temperature of the fermentation treatment is 35°C~43°C, the time is 4 h~10 h, and the predetermined acidity is 60°T~80°T.

[0020] According to an embodiment of the present application, the pretreatment includes homogenization and sterilization.

[0021] According to an embodiment of the present application, the temperature of the homogenization treatment is 55° C. to 65° C., the primary pressure is 30 MPa to 50 MPa, and the secondary pressure is 100 MPa to 250 MPa.

[0022] According to an embodiment of the present application, the temperature of the sterilization treatment is 90°C to 98°C, and the time is 240 s to 360 s.

[0023] According to an embodiment of the present application, after the sterilization treatment, the obtained liquid is cooled to 35°C~43°C.

[0024] According to an embodiment of the present application, the additive includes jam, and the method for preparing the jam includes: mixing sugar, juice and the alkaline buffer salt and performing the sterilization treatment; the sterilization treatment time is 4 min to 6 min.

[0025] According to an embodiment of the present application, the yogurt base and additives are mixed in a sterile environment.

[0026] According to an embodiment of the present application, the sterilization treatment is performed by radio frequency sterilization.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 A diagram showing pH values ​​of yogurt with different starter cultures according to one embodiment of the present application is shown; Figure 2 A graph showing pH values ​​of yogurt during shelf life according to one embodiment of the present application is shown. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0030] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0031] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0032] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0033] The present application proposes yogurt and a preparation method thereof, which will be described in detail below.

[0034] yogurt In one aspect of the present application, the present application proposes yogurt. According to an embodiment of the present application, the pH value of the yogurt is 4.7~6.5, and the yogurt includes: a yogurt base and an additive, the additive contains an alkaline buffer salt, and the alkaline buffer salt includes at least one of sodium bicarbonate, disodium hydrogen phosphate and sodium acetate; the raw materials of the yogurt base include a starter, and the starter includes at least one of the starter YO-PROX 600M, the starter Cremoso1.0, the starter PIONEER-02, the starter YoFlex®mild 1.0 and the starter YoFlex®Premium 1.0; the preparation method of the additive includes a sterilization treatment, and the temperature of the sterilization treatment is 140℃~150℃. As a result, the yogurt has the advantages of low sourness, high nutritional value, long shelf life and a wide range of applicable people.

[0035] It should be noted that the additives added to the yogurt of the present application are food raw materials, which may include jam and / or cereal products.

[0036] The alkaline buffer salts of the present application can effectively neutralize the acidic substances in the yogurt base, among which sodium bicarbonate has a better overall effect. Moreover, the above substances can be safely added to food, while alkaline substances such as sodium hydroxide are not allowed to be added to food.

[0037] According to an embodiment of the present application, based on the total mass of the additive, the content of the alkaline buffer salt is 0.05‰~0.4‰, such as 0.05‰, 0.1‰, 0.15‰, 0.2‰, 0.25‰, 0.3‰, 0.35‰, 0.4‰. Thus, the acidic substances in the yogurt base can be effectively neutralized, so that the acidity of the yogurt is low, and the flavor and taste of the additive are suitable.

[0038] According to an embodiment of the present application, the sterilization temperature is 140°C to 150°C, such as 140°C, 142°C, 144°C, 145°C, 146°C, 148°C, and 150°C, and the time is 4 min to 6 min, such as 4 min, 5 min, and 6 min. Under this sterilization condition, the bacteria can be effectively killed, and the poor flavor, taste, and texture of the jam caused by high sterilization temperature or long sterilization time can be avoided.

[0039] According to an embodiment of the present application, based on the total mass of the yogurt base, the amount of the additive added is 5% to 10%, for example, 5%, 6%, 7%, 8%, 9%, 10%. Thus, the alkaline buffer salt in the additive can neutralize the acidic substances in the yogurt base to reduce the acidity of the yogurt, and can also provide the yogurt base with the flavor and taste of the additive, thereby improving the flavor and taste of the product as a whole.

[0040] According to an embodiment of the present application, the pH value of the yogurt is 4.7 to 6.5, such as 4.7, 4.8, 4.9, 5.0, 5.2, 5.5, 5.6, 5.8, 6.0, 6.2, 6.5, preferably 5.0 to 6.5. Thus, the acidity of the yogurt is low. If the pH value continues to increase, the yogurt will be neutral or alkaline, which will not only change the unique flavor and taste of the yogurt base, reduce its natural antiseptic ability, but also may affect the survival of the active fermentation agent in the yogurt base, thereby reducing its health benefits.

[0041] According to an embodiment of the present application, the raw materials of the yogurt base include at least one of raw cow's milk and reconstituted milk and at least one of the following: a sweetener and a stabilizer.

[0042] According to an embodiment of the present application, the raw materials of the jam include sugar and fruit juice.

[0043] In another aspect of the present application, the present application proposes a method for preparing the aforementioned yogurt. According to an embodiment of the present application, the method comprises: mixing the yogurt base and an additive to obtain the yogurt, and the preparation method of the additive comprises a sterilization treatment, and the temperature of the sterilization treatment is 140°C to 150°C. The features and advantages described above for yogurt are also applicable to this method and will not be repeated here.

[0044] According to an embodiment of the present application, the method for preparing the yogurt base comprises: fermenting the starter and the pretreated yogurt base raw materials, and when the fermentation liquid reaches a predetermined acidity, demulsifying the obtained fermentation liquid to obtain the yogurt base.

[0045] According to an embodiment of the present application, the temperature of the fermentation treatment is 35°C to 43°C, such as 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, 41°C, 42°C, and 43°C, and the time is 4 h to 10 h, such as 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, and 10 h. The predetermined acidity is 60°T to 80°T, such as 60°T, 65°T, 70°T, 75°T, and 80°T. Under these fermentation conditions, the starter can maintain better growth conditions and activity, thereby promoting the production of acidic substances such as lactic acid and achieving appropriate acidity and flavor.

[0046] According to the embodiment of the present application, the pretreatment includes homogenization and sterilization. The homogenization can make the liquid more uniform and delicate, and prevent fat from floating. The sterilization can kill miscellaneous bacteria and extend the shelf life of yogurt.

[0047] According to an embodiment of the present application, the temperature of the homogenization treatment is 55°C to 65°C, such as 55°C, 56°C, 58°C, 60°C, 62°C, 64°C, and 65°C, the primary pressure is 30 MPa to 50 MPa, such as 30 MPa, 32 MPa, 35 MPa, 38 MPa, 40 MPa, 42 MPa, 45 MPa, 48 MPa, and 50 MPa, and the secondary pressure is 100 MPa to 250 MPa, such as 100 MPa, 120 MPa, 150 MPa, 180 MPa, 200 MPa, 220 MPa, and 250 MPa. Thus, the fat globules in the yogurt can be evenly dispersed to prevent the fat from floating, thereby improving the stability and uniformity of the product and enhancing the fineness of the taste.

[0048] According to an embodiment of the present application, the temperature of the sterilization treatment is 90°C to 98°C, such as 90°C, 92°C, 94°C, 95°C, 96°C, and 98°C, and the time is 240 s to 360 s, such as 240 s, 264 s, 288 s, 300 s, 324 s, 348 s, and 360 s. In this way, the bacteria can be effectively killed and the loss of nutrients can be reduced.

[0049] According to an embodiment of the present application, after the sterilization treatment, the obtained liquid is cooled to 35° C. to 43° C., for example, 35° C., 36° C., 38° C., 40° C., 42° C., 43° C. Thus, high temperature is prevented from affecting the activity of the starter.

[0050] According to an embodiment of the present application, the preparation method of the jam comprises: mixing sugar, juice and the alkaline buffer salt and sterilizing; the temperature of the sterilization treatment is 140°C to 150°C, such as 140°C, 142°C, 144°C, 145°C, 146°C, 148°C, 150°C, and the time is 4 min to 6 min, such as 4 min, 5 min, 6 min. The usual jam is acidic and has antibacterial properties, and the requirements for sterilization are not high. However, the present application adds alkaline buffer salts to the jam, which causes the jam to be alkaline, so the requirements for the sterilization conditions of the jam are high, and high temperature sterilization is required, but too high a temperature will destroy the texture and taste of the jam. Therefore, the inventor takes into account the sterilization effect and texture and taste and optimizes and selects the above-mentioned preferred sterilization temperature and time. Therefore, under this sterilization condition, it is possible to effectively kill miscellaneous bacteria and avoid the poor flavor, taste and texture of the jam caused by high sterilization temperature or long time.

[0051] According to the embodiment of the present application, the sterilization treatment is carried out by radio frequency sterilization. Thus, the high temperature sterilization requirements can be met. The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0052] Example 1 In this example, yogurt was prepared according to the following method: 1. Prepare yogurt base: (1) Ingredients: Heat raw milk to 45°C.

[0053] (2) Preheating: The preheating temperature is 60°C.

[0054] (3) Homogenization: Stir evenly and then homogenize (temperature is 60°C, primary pressure is 40MPa, secondary pressure is 200MPa). (4) Pasteurization: pasteurize the prepared liquid at 95℃ for 300s. After pasteurization, cool the liquid to 35-43℃.

[0055] (5) Fermentation: Add fermented milk starter 600M (YO-PROX 600M), keep warm and ferment at 42°C for 5 hours. When the fermentation end point of 70°T is reached, break the emulsion to obtain a yogurt base.

[0056] 2. Preparing Jam Mix 25% white sugar, 30% fruit particles and 0.1‰ (based on the total mass of the jam) sodium bicarbonate, and sterilize the resulting mixture at 145°C for 5 minutes by radio frequency to obtain jam.

[0057] 3. Mix the yogurt base and jam in a sterile environment at a mass ratio of 10% to obtain yogurt, and the pH value of the yogurt is 5.5.

[0058] Embodiment 2-5 In this example, yogurt was prepared according to the following method: (1) Ingredients: Heat raw milk to 45°C.

[0059] (2) Preheating: The preheating temperature is 60°C.

[0060] (3) Homogenization: Stir evenly and then homogenize (temperature is 60°C, primary pressure is 40MPa, secondary pressure is 200MPa). (4) Pasteurization: pasteurize the prepared liquid at 95℃ for 300s. After pasteurization, cool the liquid to 35-43℃.

[0061] (5) Fermentation: Add starter culture 600M (YO-PROX 600M), Cremoso (Cremoso1.0), HTLP (PIONEER-02), Mild 1.0 (YoFlex®mild 1.0), P1 (YoFlex®Premium 1.0), YO-MIX883, P11 (YoFlex®Premium 11), and P12 (YoFlex®Premium 12) respectively, ferment at 42°C for 5 hours, break the emulsion, and obtain yogurt.

[0062] The pH value of yogurt and the acidity value stored at 2-10℃ for 30 days were measured respectively. o T). The results are as follows Figure 1 and Figure 2As shown. It can be seen that the acid production of starter 600M (YO-PROX 600M), Cremoso (Cremoso1.0), HTLP (PIONEER-02), Mild 1.0 (YoFlex®mild 1.0) and P1 (YoFlex®Premium 1.0) is low, the acid production rate in the same time is also correspondingly low, and the acidity value increases slowly during the shelf life. Among them, the starter 600M has the best effect. Cremoso (Cremoso1.0), HTLP (PIONEER-02), Mild 1.0 (YoFlex®mild 1.0) and P1 (YoFlex®Premium 1.0) were used as starter and fermented using the method of Example 1. The pH value of the prepared yogurts all met 5.0~6.5, and the flavor, taste and texture were good. Overall, the starter 600M was the best.

[0063] Embodiment 6-8 Yogurt was prepared according to the method of Example 1, except that sodium bicarbonate was replaced by disodium hydrogen phosphate, sodium acetate and water respectively.

[0064] The pH values ​​of the yogurts prepared in Examples 1 and 6-8 were tested respectively, and the results are shown in Table 1. It can be seen that among the three alkaline buffer salts of sodium bicarbonate, disodium hydrogen phosphate and sodium acetate, sodium bicarbonate can significantly improve the acidity of the yogurt base, and the effect is better.

[0065] Table 1 pH values ​​of yogurt prepared with different alkaline substances

[0066] Examples 9-11 Yogurt was prepared according to the method of Example 1, except that the amount of sodium bicarbonate added was replaced with 0.2‰, 0.3‰, and 0.4‰.

[0067] The pH values ​​of the yogurts prepared in Examples 1 and 9-11 were tested respectively, and the results are shown in Table 2. It can be seen that the acidity of the yogurt base can be improved by using 0.1‰~0.4‰ sodium bicarbonate, among which 0.3‰ and 0.4‰ have better effects.

[0068] Table 2 pH values ​​of yogurt prepared with different amounts of sodium bicarbonate added

[0069] Comparative Example 1 In this comparative example, yogurt was prepared according to the following method: 1. Prepare yogurt base: (1) Ingredients: Heat raw milk to 45°C.

[0070] (2) Preheating: The preheating temperature is 60°C.

[0071] (3) Homogenization: Stir evenly and then homogenize (temperature is 60°C, primary pressure is 40MPa, secondary pressure is 200MPa). (4) Pasteurization: pasteurize the prepared liquid at 95℃ for 300s. After pasteurization, cool the liquid to 35-43℃.

[0072] (5) Fermentation: Add fermented milk starter 600M (YO-PROX 600M) and 0.02‰ sodium bicarbonate, and ferment at 42°C for 5 hours. When the fermentation end point of 70°T is reached, the emulsion is broken to obtain yogurt.

[0073] The results are as follows: the pH value of the yogurt is 4.45, the acidity is 70°T, and the overall yogurt taste has not been significantly improved by reducing the acidity.

[0074] Comparative Example 2 In this comparative example, yogurt was prepared according to the following method: 1. Prepare yogurt base: (1) Ingredients: Heat raw milk to 45°C.

[0075] (2) Preheating: The preheating temperature is 60°C.

[0076] (3) Homogenization: Stir evenly and then homogenize (temperature is 60°C, primary pressure is 40MPa, secondary pressure is 200MPa). (4) Pasteurization: pasteurize the prepared liquid at 95℃ for 300s. After pasteurization, cool the liquid to 35-43℃.

[0077] (5) Fermentation: Add fermented milk starter 600M (YO-PROX 600M) and 0.1‰ sodium bicarbonate, and ferment and demulsify at 42°C to obtain yogurt.

[0078] The results are as follows: Since the amount of sodium bicarbonate added was 0.1‰, the overall fermentation rate was reduced. After adding sodium bicarbonate, the overall fermentation rate was reduced, the product did not coagulate, and the fermentation failed.

[0079] Comparative Example 3 In this comparative example, yogurt was prepared according to the following method: 1. Prepare yogurt base: (1) Ingredients: Heat raw milk to 45°C.

[0080] (2) Preheating: The preheating temperature is 60°C.

[0081] (3) Homogenization: Stir evenly and then homogenize (temperature is 60°C, primary pressure is 40MPa, secondary pressure is 200MPa). (4) Pasteurization: pasteurize the prepared liquid at 95℃ for 300s. After pasteurization, cool the liquid to 35-43℃.

[0082] (5) Fermentation: Add fermented milk starter 600M (YO-PROX 600M), keep warm and ferment at 42°C for 5 hours. When the fermentation end point of 70°T is reached, break the emulsion to obtain a yogurt base.

[0083] 2. After the sodium bicarbonate is sterilized (95°C, 3 min), the yogurt base is mixed with 0.1‰ (based on the total mass of the yogurt base) of the sterilized sodium bicarbonate to obtain yogurt.

[0084] The results are as follows: Sodium bicarbonate will decompose after sterilization, which will reduce the amount of sodium bicarbonate added to the yogurt base. Moreover, the decomposed product of sodium bicarbonate will be added to the yogurt base, which will make the yogurt taste alkaline. The acidity after mixing is 70 o T, pH value is 4.5, which cannot achieve the purpose of reducing acid.

[0085] Comparative Example 4 Yogurt was prepared according to the method of Example 1, except that the jam was sterilized at 135° C. for 3 min.

[0086] Comparative Example 5 Yogurt was prepared according to the method of Example 1, except that the jam was sterilized at 155° C. for 7 min.

[0087] The microbial colony count and taste of the yogurt prepared in Example 1 and Comparative Examples 4 and 5 were tested respectively, wherein the taste evaluation was obtained by tasting by 10 professional analysts. The results are shown in Table 3. It can be seen that the jam sterilization conditions in Example 1 are better, which can effectively kill miscellaneous bacteria, and the taste and texture of the yogurt are better.

[0088] Table 3 Microbial residues and taste of yogurt prepared under different jam sterilization conditions

[0089] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A yogurt, characterized in that: The pH value of the yogurt is 4.7-6.5, and the yogurt comprises: a yogurt base and an additive, wherein the additive contains an alkaline buffer salt, and the alkaline buffer salt comprises at least one of sodium bicarbonate, disodium hydrogen phosphate and sodium acetate; The raw materials of the yogurt base include a fermentation agent, and the fermentation agent includes at least one of a fermentation agent YO-PROX 600M, a fermentation agent Cremoso 1.0, a fermentation agent PIONEER-02, a fermentation agent YoFlex®mild 1.0, and a fermentation agent YoFlex®Premium 1.0; The preparation method of the additive includes sterilization treatment, and the temperature of the sterilization treatment is 140°C to 150°C.

2. The yogurt according to claim 1, characterized in that Based on the total mass of the additive, the content of the alkaline buffer salt is 0.05‰~0.4‰; The alkaline buffer salt includes sodium bicarbonate; The additives include jam and / or cereal products.

3. The yogurt according to claim 1, characterized in that The sterilization treatment time is 4 min to 6 min.

4. The yogurt according to any one of claims 1 to 3, characterized in that Based on the total mass of the yogurt base, the amount of the additive added is 5% to 10%; The pH value of the yogurt is 5.0-6.

5.

5. The yogurt according to claim 1, characterized in that The raw materials of the yogurt base include at least one of raw cow's milk and reconstituted milk and at least one of the following: a sweetener and a stabilizer.

6. A method for preparing the yogurt according to any one of claims 1 to 5, characterized in that: include: Mixing the yogurt base and the additive to obtain the yogurt; The preparation method of the additive includes sterilization treatment, and the temperature of the sterilization treatment is 140°C to 150°C.

7. The method according to claim 6, characterized in that The yogurt base and additives are mixed in a sterile environment; The preparation method of the yogurt base comprises: Fermenting the starter with the pretreated yogurt base material, and when the fermentation liquid reaches a predetermined acidity, demulsifying the obtained fermentation liquid to obtain the yogurt base; The fermentation temperature is 35°C to 43°C, the fermentation time is 4 h to 10 h, and the predetermined acidity is 60°T to 80°T; The pretreatment includes homogenization and sterilization; The temperature of the homogenization treatment is 55°C to 65°C, the primary pressure is 30 MPa to 50 MPa, and the secondary pressure is 100 MPa to 250 MPa; The sterilization temperature is 90°C to 98°C and the time is 240 s to 360 s; After the sterilization treatment, the obtained liquid is cooled to 35°C-43°C.

8. The method according to claim 6, characterized in that The additive includes jam, and the preparation method of the jam includes: mixing sugar, juice and the alkaline buffer salt and performing the sterilization treatment; The sterilization treatment time is 4 min to 6 min.

9. The method according to claim 6, characterized in that The sterilization treatment is carried out by radio frequency sterilization.

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