A yoghurt and a method for preparing the same

Abstract

The application provides a yoghurt, which comprises the following raw materials in parts by weight: raw cow milk 800-950 parts; lactose powder or desalted whey powder 0-50 parts; whey protein powder 0-15 parts; stabilizer 0-25 parts; lactase 0.3-2.0 parts; and fermentation bacteria 100-200 U. The application controls the adding amount of lactase, enzyme hydrolysis parameters, the adding amount of lactose powder or desalted whey powder and combines specific bacteria, so that the final product has high content of galacto-oligosaccharide, low total sugar content, high content of compound prebiotics, clean label claim requirements and low GI food requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of food technology, in particular to a yogurt and a preparation method thereof. BACKGROUND

[0002] The concept of prebiotics was proposed by Glen Gibson, the international "father of prebiotics" in 1995, which refers to some organic substances that are not digested and absorbed by the host but can selectively promote the metabolism and proliferation of beneficial bacteria in the body, thereby improving the health of the host.

[0003] A successful prebiotic should not be digested in the upper digestive tract and can be fermented by intestinal flora. Most importantly, it can only stimulate the growth of beneficial bacteria and not harmful bacteria with potential pathogenic or spoilage activity. The most basic prebiotic is a carbohydrate, but non-carbohydrate substances used as prebiotics are not excluded by definition. In theory, any antibiotic that can reduce harmful bacteria and promote the growth of beneficial bacteria or activities can be called a prebiotic. Since prebiotics cannot be decomposed, absorbed and utilized by the human body, after passing through the digestive tract to the colon, some can be decomposed and utilized by the colon flora, promoting the growth of the colon flora, which is of great significance in improving intestinal microecology and promoting lipid, protein and mineral metabolism, so it is increasingly widely used in the fields of food, feed and the like.

[0004] Common prebiotics include oligosaccharides, including fructooligosaccharides, galactooligosaccharides, xylooligosaccharides, isomaltooligosaccharides, soybean oligosaccharides, inulin, and some microalgae such as spirulina and arthrospira, in addition to polysaccharides (such as grifolan, hemoglobin polysaccharides), protein hydrolysates (such as casein hydrolysate, alpha-lactalbumin, lactoferrin, etc.) and vegetables, Chinese herbal medicines, wild plants and other natural plants can also be used as prebiotics.

[0005] Galactooligosaccharides (GOS) is a functional oligosaccharide with natural properties, and its molecular structure is generally 1-7 galactosyl groups connected to a galactose or glucose molecule, i.e. Gal-(Gal)n-Glc / Gal (n is 0-6). In nature, there is a small amount of GOS in animal milk, and the content in human breast milk is relatively high, and the establishment of the bifidobacterium flora in infants depends largely on the GOS components in breast milk.

[0006] Therefore, it is necessary to develop a yogurt with high prebiotic content. SUMMARY

[0007] Therefore, the technical problem to be solved by the present application is to provide a yogurt, and the yogurt provided by the present application has high galactooligosaccharide content and low total sugar content.

[0008] The present application provides a kind of yoghurt, including the following weight parts of raw materials:

[0009] 800-950 parts of raw cow milk; 0-50 parts of lactose powder or desalted whey powder; 0-15 parts of whey protein powder; 0-25 parts of stabilizer; 0.3-2.0 parts of lactase; 100-200 U of fermentation bacteria.

[0010] Preferably, the lactase is NOLAFIBER lactase or Nurica lactase.

[0011] Preferably, the fermentation bacteria is lactose-negative bacteria Addifix.

[0012] The stabilizer includes one or several of physical starch or citrus fiber.

[0013] Preferably, the content of galacto-oligosaccharide in the yoghurt is 1.5-4.0 g / 100 mL, and the total sugar content is <5%.

[0014] The present application provides a preparation method of the yoghurt according to any one of the above technical solutions, comprising:

[0015] A) mixing one of desalted whey powder or lactose powder with raw cow milk, stabilizer and whey protein powder to obtain fermentation base;

[0016] B) subjecting the fermentation base to material preparation, degassing, homogenization and sterilization, adding fermentation bacteria and lactase for fermentation and enzymolysis;

[0017] C) after fermentation, stirring, breaking emulsion, sterilization and enzyme inactivation, obtaining the yoghurt.

[0018] Preferably, the content of lactose in the fermentation base of step A) is 6.0%-8.0%.

[0019] Preferably, the material preparation temperature is 50-55℃, and the material preparation time is 5-20 min; the degassing temperature is 40-70℃, and the degassing vacuum degree is -50 to -80 kpa; the homogenization is 200-250 bar.

[0020] Preferably, the sterilization of step B) is 95-138℃ for 4 s-300 s.

[0021] Preferably, the fermentation and enzymolysis temperature of step B) is 39-42℃; the fermentation end point pH is 4.3-4.45, and the titration acidity is 72°.

[0022] Preferably, the stirring and emulsion breaking of step C) is stirring at 20-30 revolutions per minute for 1-2 minutes; and the sterilization and enzyme inactivation parameters are 75-77℃ for 25 s.

[0023] Compared with the prior art, the yoghurt provided by the application comprises raw cow milk 800-950 parts by weight, lactose powder or desalted whey powder 0-50 parts by weight, whey protein powder 0-15 parts by weight, stabilizer 0-25 parts by weight, lactase 0.3-2.0 parts by weight, and fermentation bacteria 100-200 U. The content of galacto-oligosaccharide in the final product is high, the total sugar content is low, the content of complex prebiotics is high, and the requirements of low GI food are met by controlling the addition amount of lactase, the enzyme hydrolysis parameters, the addition amount of lactose powder or desalted whey powder, and the specific bacteria. DETAILED DESCRIPTION

[0024] The yoghurt provided by the application comprises raw cow milk 800-950 parts by weight, lactose powder or desalted whey powder 0-50 parts by weight, whey protein powder 0-15 parts by weight, stabilizer 0-25 parts by weight, lactase 0.3-2.0 parts by weight, and fermentation bacteria 100-200 U.

[0025] The yoghurt provided by the application comprises raw cow milk 800-950 parts by weight, lactose powder or desalted whey powder 0-50 parts by weight, whey protein powder 0-15 parts by weight, stabilizer 0-25 parts by weight, lactase 0.3-2.0 parts by weight, and fermentation bacteria 100-200 U.

[0026] The yoghurt provided by the application comprises raw cow milk 800-950 parts by weight, lactose powder or desalted whey powder 0-50 parts by weight, whey protein powder 0-15 parts by weight, stabilizer 0-25 parts by weight, lactase 0.3-2.0 parts by weight, and fermentation bacteria 100-200 U.

[0027] The above weight parts of the application are equivalent to mass percentages when the total amount is 100, and are equivalent to wt‰ when the total amount is 1000.

[0028] The yoghurt provided by the application comprises raw cow milk 800-950 parts by weight, lactose powder or desalted whey powder 0-50 parts by weight, whey protein powder 0-15 parts by weight, stabilizer 0-25 parts by weight, lactase 0.3-2.0 parts by weight, and fermentation bacteria 100-200 U.

[0029] The raw cow milk is not limited in the application, and is well known to those skilled in the art.

[0030] The raw cow milk is rich in protein, minerals, growth factors and various nutrients, and is an ideal fermentation main body base material for the yoghurt. In the yoghurt system, the raw cow milk mainly plays two roles, one is to provide carbon source, nitrogen source and trace elements for microbial fermentation, and the other is to impart smooth taste and texture to the yoghurt and provide various nutrients necessary for the human body.

[0031] The yoghurt provided by the application comprises lactose powder or desalted whey powder 0-50 parts by weight, preferably 5-50 parts by weight, and more preferably 10-50 parts by weight.

[0032] The lactose powder or the desalted whey powder is not limited in the present application, and can be commercially available.

[0033] The lactose powder or the desalted whey powder in the present application is mainly used to provide sufficient lactose in the dairy product, so as to provide a substrate for enzymatic hydrolysis, and to achieve the purpose of producing sufficient galacto-oligosaccharides by enzymatic hydrolysis.

[0034] The yogurt provided by the present application comprises 0-15 parts by weight of whey protein powder; preferably 1-12 parts by weight; more preferably 2-10 parts by weight.

[0035] The whey protein powder is not limited in the present application, and can be commercially available.

[0036] The yogurt provided by the present application comprises 0-25 parts by weight of stabilizer; preferably 5-24 parts by weight; more preferably 7-23 parts by weight.

[0037] The stabilizer comprises one or more of physical starch or citrus fiber.

[0038] The mutual compounding of the above-mentioned stabilizers can make the fermented milk protein molecules uniformly distributed in the system, effectively improve the protein flocculation, and realize the thick feeling and state stability of the product.

[0039] The added stabilizer in the present application belongs to the category of food raw materials, and can maximize the clean product ingredient label.

[0040] The product of the present application can achieve a thick taste by precisely adjusting the stabilizer formula of the product without using a large amount of colloid or other chemically modified starch.

[0041] The yogurt provided by the present application comprises 0.3-2.0 parts of lactase; preferably 0.5-1.7 parts; more preferably 0.7-1.5 parts.

[0042] The lactase is NOLAFIBER lactase or Nurica lactase.

[0043] The specific lactase can hydrolyze lactose to obtain galacto-oligosaccharides.

[0044] The yogurt provided by the present application comprises 100-200 U of fermentation bacteria.

[0045] The fermentation bacteria is Addifix lactose-negative bacteria.

[0046] The above-mentioned lactose-negative bacteria can effectively reduce the GI value of the product and improve the health properties of the product.

[0047] According to the application, the content of galacto-oligosaccharide in the yogurt is 1.5-4.0 g / 100 mL, and the total sugar content is less than 5%.

[0048] The application provides a preparation method of the yogurt.

[0049] A) one of desalted whey powder or lactose powder is mixed with raw cow milk, a stabilizer and whey protein powder to obtain a fermentation base;

[0050] B) the fermentation base is subjected to material mixing, degassing, homogenization and sterilization, and then is subjected to fermentation and enzymolysis by adding fermentation strains and lactase;

[0051] C) after fermentation, stirring, demulsification, sterilization and enzyme inactivation are performed, and the yogurt is obtained.

[0052] The preparation method of the yogurt comprises mixing one of desalted whey powder or lactose powder with raw cow milk, a stabilizer and whey protein powder to obtain a fermentation base.

[0053] The content of lactose in the fermentation base is 6.0%-8.0%.

[0054] The components and the ratio have been clearly described above, and will not be repeated here.

[0055] The fermentation base is subjected to material mixing, and the material mixing temperature is 50-55 DEG C; the material mixing time is 5-20 min; and the material mixing equipment with mixing, dispersion, shearing and emulsification effects is preferably adopted.

[0056] Subsequently, degassing is performed, and the degassing temperature is 40-70 DEG C, and the degassing vacuum degree is -50 to -80 kpa.

[0057] After degassing, homogenization is performed, and the homogenization is 200-250 bar.

[0058] After homogenization, sterilization is performed, and the sterilization is 95-138 DEG C, 4 s-300 s.

[0059] Fermentation and enzymolysis are performed by adding fermentation strains and lactase; preferably, stirring is performed, fermentation strains and lactase are added, and fermentation and enzymolysis are performed; the time is counted from the end of the base feeding, the stirring is stopped after 5-10 min, the material mixing effect is that there is no large piece of bacteria powder aggregation in the fermentation tank, and the fermentation is carried out after standing, and demulsification is performed after the fermentation is completed.

[0060] After sterilization, the application preferably pumps the fermentation tank for fermentation.

[0061] The fermentation and enzymolysis temperature is 39-42 DEG C; the fermentation end point pH is 4.3-4.45, and the titration acidity is 72 DEG.

[0062] After fermentation, stirring, breaking emulsion, sterilization and enzyme inactivation are carried out, and then the yogurt is obtained.

[0063] Specifically, the stirring speed for breaking emulsion is 20-30 revolutions per minute, and the stirring time is 1-2 minutes.

[0064] The parameters for sterilization and enzyme inactivation are specifically 75-77℃ and 25s.

[0065] The present application adjusts the lactose content in the milk base of the yogurt, selects specific lactase, and combines the addition amount of lactase and the enzyme hydrolysis time to make the conversion efficiency of lactose into galacto-oligosaccharide reach the highest, and controls the pH value of the yogurt and the enzyme inactivation temperature and time, so that the lactase in the yogurt is inactivated, so that it does not continuously produce effects in the yogurt, and thus the nutritional structure of the yogurt is not affected.

[0066] The present application provides a kind of yogurt, including the following weight parts of raw materials: raw milk 800-950 parts;Lactose powder or desalted whey powder 0-50 parts;Whey protein powder 0-15 parts;Stabilizer 0-25 parts;Lactase 0.3-2.0 parts;Fermentation bacteria 100-200 U.The present application controls the addition amount of lactase, enzyme hydrolysis parameters, the addition amount of lactose powder or desalted whey powder, and specific strains to make the final product have high galacto-oligosaccharide content, low total sugar content, high prebiotic content, and low GI food requirements.

[0067] The present application will be further described below in combination with examples:

[0068] In the following examples, the yogurt formula is as follows:

[0069] 1, NOLA FIBER lactase supplier is Kossuth or Nurica lactase supplier is Danisco.

[0070] 2, Lactose-negative bacteria Addifix supplier is Kossuth.

[0071] Examples

[0072] Table 1

[0073]

[0074]

[0075] Example preparation method:

[0076] Yogurt base preparation: Standardized milk 52% of the total amount of ingredients was heated to 55℃, the stabilizer was first added to the standardized milk, the temperature of the material was kept at 55℃, the material time was kept at 10min, the material equipment with mixing, dispersion, shearing and emulsification effect was used to make the liquid into a uniform and dispersed mixture, and the desalted whey powder (or lactose powder) was added to the material system at 55℃ (to ensure that the lactose content in the liquid is 7.0%). The temperature of the material was kept at 55℃, and the material time was kept at 20min. Then degassing (degassing temperature 65℃, degassing vacuum-40kpa), homogenization (200bar), base sterilization (95℃, 300s) were carried out, and the base was pumped into the fermentation tank for fermentation.

[0077] Enzymatic hydrolysis and fermentation of yogurt: The enzymatic hydrolysis and fermentation temperature was kept at 41℃, when the remaining liquid in the ingredient tank was 50%, the stirring was started, the fermentation bacteria lactose-negative bacteria Addifix and NOLA FIBER lactase were added, the time was counted from the end of the base feeding, the stirring was stopped after 10min, the mixing effect was that there was no large piece of bacteria powder aggregation in the fermentation tank, and the fermentation was carried out, the pH was detected after 5h of fermentation, the pH of the yogurt was reduced to about 4.3, the titration acidity was above 72°T, the stirring was started to break the emulsion, the stirring speed was 20r / min, and the stirring time was 2min.

[0078] Enzyme inactivation and yogurt pasteurization: The yogurt feeding temperature was set to 25℃, the yogurt pasteurization conditions were set to 75℃ / 25s, and the outlet temperature was set to 35℃, which was stored in a sterile tank.

[0079] Filling: The filling temperature was 25℃.

[0080] Preparation method of comparative example 1:

[0081] The fermentation base preparation, filling link was consistent with example one, the fermentation and yogurt pasteurization were the same, the difference was that the ordinary Streptococcus thermophilus and Lactobacillus bulgaricus were used for fermentation, and no lactase with GOS production ability was added.

[0082] Preparation method of comparative example 2:

[0083] The fermentation base preparation, filling link was consistent with example one, the fermentation and yogurt pasteurization were the same, the difference was that no lactase with GOS production ability was added, and lactase Maxilact LAGX2000 was added.

[0084] Preparation method of comparative example 3:

[0085] The fermentation base preparation, filling link was consistent with example one, the fermentation and yogurt pasteurization were the same, the difference was that the ordinary Streptococcus thermophilus and Lactobacillus bulgaricus were used for fermentation, and no lactose-negative bacteria was used.

[0086] Preparation method of comparative example 4:

[0087] The fermentation base preparation, filling link and embodiment are consistent, the fermentation and yogurt pasteurization are the same, the difference is that the initial lactose content in the control system is 11%.

[0088] Preparation method of comparative example 5:

[0089] The fermentation base preparation, filling link and embodiment are consistent, the fermentation and yogurt pasteurization are the same, the difference is that the initial lactose content in the control system is 11%.

[0090] The experimental results are as follows, wherein the results of the embodiments are as shown in Tables 2-6, and the results of the comparative examples are as shown in Tables 7-17.

[0091] Table 2

[0092]

[0093] Table 3

[0094]

[0095]

[0096] Table 4

[0097]

[0098] Table 5

[0099]

[0100] Table 6

[0101]

[0102] Table 7

[0103]

[0104] Table 8

[0105]

[0106] Table 9

[0107]

[0108]

[0109] Table 10

[0110]

[0111] Table 11

[0112]

[0113] Table 12

[0114]

[0115] Table 13

[0116]

[0117] Table 14

[0118]

[0119] Table 15

[0120]

[0121] Table 16

[0122]

[0123] Table 17

[0124] Comparative Example 1 GI value determination (WS / T 652-2019) The GI determination value is 81 (>55), which does not meet the requirements of low GI food claims.

[0125] The above merely preferred embodiments of the present application, it should be noted that for those skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered within the scope of the present application.

Claims

1. A yogurt, characterized in that The invention comprises the following raw materials in parts by weight: 800-950 parts of raw cow's milk; 0-50 parts of lactose powder or desalted whey powder; 0-15 parts of whey protein powder; 0-25 parts of stabilizer; 0.3-2.0 parts of lactase; 100-200 U of fermentation bacteria; the fermentation bacteria is the lactose-negative bacteria Addifix; The lactase is NOLA FIBER lactase or Nurica lactase.

2. The yogurt according to claim 1, characterized in that The stabilizer includes one or more of physical starch or citrus fiber.

3. The yogurt according to claim 1, characterized in that The content of galacto-oligosaccharide in the yogurt is 1.5-4.0 g / 100 mL, and the total sugar content is less than 5%.

4. A method for preparing yogurt according to any one of claims 1 to 3, characterized in that: include: A) mixing one of desalted whey powder or lactose powder with raw milk, a stabilizer, and whey protein powder to obtain a fermentation base; B) the fermentation base is chemically treated, degassed, homogenized, and sterilized, and fermentation bacteria and lactase are added to carry out fermentation and enzymolysis; C) After fermentation, stir to break the emulsion, sterilize and inactivate enzymes.

5. The preparation method according to claim 4, characterized in that Step A): the lactose content in the fermentation base is 6.0% to 8.0%.

6. The preparation method according to claim 4, characterized in that The material temperature is 50-55° C.; the material time is 5-20 min; the degassing temperature is 40-70° C., the degassing vacuum is -50-80 kPa; and the homogenization temperature is 200-250 bar.

7. The preparation method according to claim 4, characterized in that Step B) The sterilization is carried out at 95-138° C. for 4-300 seconds.

8. The preparation method according to claim 4, characterized in that Step B) The fermentation and enzymatic hydrolysis temperature is 39-42° C.; the fermentation endpoint pH is 4.3-4.45, and the titrated acidity is 72°.

9. The preparation method according to claim 4, characterized in that In step C), the stirring and demulsification is performed at a speed of 20 to 30 rpm and a stirring time of 1 to 2 minutes; and the sterilization and enzyme inactivation parameters are specifically: 75 to 77° C., 25 seconds.

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