Light fermented cheese-flavored milk and preparation method thereof

Abstract

The invention provides lightly-fermented cheese-flavored milk and a preparation method thereof. The lightly-fermented cheese-flavored milk contains milk protein which is not less than 3.6 g / 100g and not more than 3.8 g / 100g, lactose which is not less than 4.5 g / 100g and not more than 5.5 g / 100g, and the acidity of the lightly-fermented cheese-flavored milk is not less than 25 DEG T. The pasteurized milk is lightly fermented by applying the combination of lactococcus lactis subsp. Lactis, lactococcus lactis subsp. Cremoris and lactococcus lactis cremoris diacetyl subsp. Cremoris, so that the milk generates the cheese fragrance, and the cheese flavor can be further released after the sodium chloride is added; and after the fermentation is finished, carrying out secondary pasteurization to inactivate lactic acid bacteria so as to prevent sour taste caused by excessive fermentation, thereby obtaining the lightly-fermented cheese-flavored milk product.

Description

Technical Field

[0001] This invention relates to the field of dairy product preparation technology, specifically to a lightly fermented cheese-flavored milk and its preparation method. Background Technology

[0002] Existing low-temperature fermented milk products on the market are mainly products fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. During fermentation, the milk undergoes structural changes, with milk proteins interacting to form a gel, increasing viscosity. The urgent problem for researchers is to develop a fermented milk that does not denature, has high stability, does not increase viscosity, possesses a fermented flavor, and simultaneously preserves taste and nutrition by changing the fermentation conditions. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention aims to provide a lightly fermented cheese-flavored milk and its preparation method, which has a cheese aroma and can maintain the smooth taste of fresh milk.

[0004] To achieve the above objectives, the present invention first provides a lightly fermented buttery milk, wherein the lightly fermented buttery milk meets the following requirements:

[0005] Milk protein content ≤ 3.6g / 100g ≤ 3.8g / 100g;

[0006] 4.5g / 100g ≤ lactose ≤ 5.5g / 100g;

[0007] 18°T ≤ Acidity ≤ 25°T.

[0008] According to a specific embodiment of the present invention, the lightly fermented buttery milk further meets the following requirements:

[0009] 115mg / 100g ≤ Sodium ≤ 120mg / 100g;

[0010] 120mg / 100g≤Natural calcium≤130mg / 100g.

[0011] The present invention also provides a method for preparing the above-mentioned lightly fermented cheesy milk, wherein the preparation method includes a step of fermenting pasteurized liquid and a step of adding auxiliary materials after fermentation.

[0012] The fermentation process uses a combination of three types of Lactococcus lactis, including Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis fat, and Lactococcus lactis fat diacetyl.

[0013] The auxiliary material is sodium chloride, and the addition amount is 0.06-0.08g / 100g. This addition amount is based on the total mass of the fermented liquid, and the liquid after adding the auxiliary material is obtained.

[0014] In the above preparation method, preferably, the lactococcus lactis is from Danisco (China) Co., Ltd. BT01LYO.

[0015] In the above preparation method, preferably, the preparation method includes the following steps: degassing, fat-milk separation, sterilization, mixing and homogenization, first pasteurization, fermentation, addition of excipients, and second pasteurization of the liquid obtained after cleaning raw milk;

[0016] More preferably, the degassing includes the following steps: degassing the liquid obtained after cleaning raw milk at a temperature of 55-65°C and a degassing pressure of -0.04 to -0.09 bar to obtain the liquid after the degassing step.

[0017] More preferably, the fat-milk separation includes the following steps: preheating the degassed liquid to 55-65°C and centrifuging it to obtain skim milk and light cream.

[0018] More preferably, the sterilization includes the following steps: physically sterilizing skim milk using a sterilization separator at a temperature of 50-60°C and a centrifuge speed of 5000-10000 rpm to obtain skim milk after physical sterilization; and sterilizing light cream at a high temperature of 121-132°C for 1-15 seconds, and then lowering the temperature of the light cream to 30-55°C after sterilization to obtain light cream after high-temperature sterilization.

[0019] More preferably, the mixing and homogenization includes the following steps: mixing skim milk after physical sterilization and light cream after high-temperature sterilization online to obtain a mixed liquid; homogenizing the mixed liquid in a sterile environment at a homogenization pressure of 30 / 170-220 bar and a homogenization temperature of 50-65°C to obtain a homogenized liquid.

[0020] More preferably, the first pasteurization includes the following steps: indirectly pasteurizing the homogenized liquid at a temperature of 62-65°C for 25-35 minutes, or at a temperature of 72-75°C for 12-15 seconds, using plate pasteurization or tubular pasteurization, to obtain the first pasteurized liquid.

[0021] More preferably, the fermentation includes the following steps: cooling the liquid after the first pasteurization to 30-40℃, mixing the inoculum into the liquid and stirring evenly, with an addition amount of 2.1-2.2g / 100kg to obtain the inoculated liquid, and fermenting the inoculated liquid for 4-6 hours at a fermentation temperature of 28-32℃ to obtain the fermented liquid.

[0022] More preferably, the second pasteurization includes the following steps: performing a second pasteurization on the feed liquid after adding excipients, with a pasteurization temperature of 62-65℃ and a pasteurization time of 25-35 minutes, or a pasteurization temperature of 72-75℃ and a pasteurization time of 12-15 seconds, and the pasteurization method being plate pasteurization or tube pasteurization, to obtain lightly fermented buttery milk.

[0023] According to a specific embodiment of the present invention, preferably, the method for preparing fermented cheese-flavored milk includes the following specific steps:

[0024] (1) Provide raw milk.

[0025] (2) Degassing: In this step, the liquid obtained after cleaning raw milk is degassed to obtain degassed liquid, so as to remove undesirable gases and volatile components in the raw milk, inhibit bacterial growth, prevent the generation of bubbles and fermentation during milk storage and packaging, and extend shelf life; the degassing treatment can be carried out at a temperature of 55-65℃ and a pressure of -0.04 bar to -0.09 bar to improve the flavor and taste of the product.

[0026] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0027] (4) Physical sterilization of skim milk: The skim milk treated in step (3) is sterilized by a sterilization separator to obtain physically sterilized skim milk liquid, which improves sterilization efficiency, reduces microbial residue rate, and at the same time ensures the nutritional components of the product and extends the product shelf life. Sterilization by the sterilization separator can be carried out at a temperature of 50-60℃ and a centrifugal force of 5000-10000rpm. The sterilization separator can remove about 98% of anaerobic spore microorganisms and 95% of aerobic spore bacteria from the milk, which can cumulatively reduce the total number of bacteria in the milk by about 86% and improve product quality.

[0028] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 121-132℃ for 1-15 seconds. After sterilization, the light cream is cooled to 30-55℃ to obtain high-temperature sterilized light cream.

[0029] (6) Online mixing: The skim milk liquid that has been physically sterilized and the light cream that has been sterilized at high temperature are mixed at a mixing temperature of 50-65℃ to obtain the mixed liquid.

[0030] (7) Homogenization: In this step, the mixed liquid is homogenized to obtain a homogenized liquid. This step prevents fat from rising and separating, making the fat globules in the milk more evenly dispersed in the milk, resulting in a more stable and uniform consistency, improving the taste and smoothness of the milk, and enhancing its digestibility and absorption rate. Homogenization can be carried out at a temperature of 50-65℃ and a pressure of 30 / 170-220 bar (first adjust the secondary pressure to 30 bar, then adjust the primary pressure to 170-220 bar) to further improve product stability and flavor.

[0031] (8) Pasteurization: In this step, the homogenized liquid is pasteurized to obtain a pasteurized liquid. Traditional plate or tube pasteurization methods are used to further remove harmful microorganisms from the liquid while preserving the product's active nutrients to the greatest extent. Pasteurization can be carried out at a temperature of 62-65℃ for 25-35 minutes or at a temperature of 72-75℃ for 12-15 seconds. This effectively kills pathogenic bacteria in the liquid, ensuring product safety while better preserving the product's nutrients and natural flavor.

[0032] (9) Inoculation: In this step, the pasteurized liquid is inoculated with fermentation starters. When the temperature of the liquid drops to 30-40℃, the fermentation starters are mixed into the liquid and stirred evenly to obtain the inoculated liquid. Inoculation can be carried out at a temperature of 30-40℃, with an inoculation amount of 2.16g / 100kg. Under these conditions, the fermentation starters are suitable for growth and reproduction in the milk system and can produce a good cheese flavor in the product.

[0033] (10) Fermentation: In this step, the inoculated liquid is fermented using a constant temperature fermentation method to promote the growth of fermentation bacteria and produce a unique cheese aroma, resulting in fermented liquid. Fermentation can be carried out at a temperature of 28-32℃ for 4-6 hours, which can produce different kinds of cheese aroma, enhance the deliciousness of the product, and enrich the flavor profile of the product.

[0034] (11) Adding auxiliary materials: In this step, sodium chloride is added to the fermented liquid at a rate of 0.06-0.08 g / 100 g. This amount of sodium chloride can enhance the release of the cheese aroma, maintain the unique cheese aroma of the product and control the acidity, thus obtaining the liquid after adding auxiliary materials.

[0035] (12) Secondary pasteurization: In this step, the feed liquid after the addition of excipients is subjected to secondary pasteurization using traditional plate or tube pasteurization methods. This inactivates the fermentation bacteria and other microorganisms in the feed liquid, ensuring stable product quality and flavor throughout the shelf life, while preserving the aroma components of the product to the greatest extent possible. The resulting feed liquid is pasteurized twice. Secondary pasteurization can be carried out at a temperature of 62-65℃ for 25-35 minutes or at a temperature of 72-75℃ for 12-15 seconds, and the time from the start of secondary pasteurization to filling should not exceed 1 hour.

[0036] (13) Filling: In this step, the pasteurized liquid is quantitatively filled and cooled to 2-10℃ and poured into a container that can withstand a pressure of not less than 0.6kg to prevent the container from exploding during the sterilization process when the pressure of the container is insufficient.

[0037] The technical solution of the present invention has the following beneficial technical effects:

[0038] This invention uses cheese bacteria to lightly ferment pasteurized milk, which produces a cheese aroma. Adding sodium chloride can further release the cheese flavor. After fermentation, a second pasteurization is performed to inactivate the lactic acid bacteria, thus preparing a lightly fermented cheese-flavored milk product. Detailed Implementation

[0039] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0040] Example 1:

[0041] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0042] (1) Provide raw milk;

[0043] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 55℃ and a deaeration pressure of -0.09 bar to obtain the deaerated liquid.

[0044] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0045] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 50°C and a centrifuge speed of 5000 rpm to obtain skim milk that has undergone physical sterilization.

[0046] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 121°C for 4 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain light cream that has been sterilized at high temperature.

[0047] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0048] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 170 bar and a temperature of 50°C to obtain a homogenized liquid.

[0049] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 62℃, and the sterilization time is 25 minutes to obtain the liquid after first pasteurization.

[0050] (9) Inoculation: The liquid after the first pasteurization is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0051] (10) Fermentation: The inoculated liquid is fermented for 4 hours at a temperature of 32°C to obtain the fermented liquid.

[0052] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.06 g / 100 g to obtain the liquid after adding auxiliary materials;

[0053] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 62°C for 25 minutes to obtain the feed solution after the second pasteurization.

[0054] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0055] Example 2:

[0056] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0057] (1) Provide raw milk;

[0058] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 60°C and a deaeration pressure of -0.07 bar to obtain the deaerated liquid.

[0059] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0060] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 55°C and a centrifuge speed of 7000 rpm to obtain skim milk that has undergone physical sterilization.

[0061] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 130°C for 3 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0062] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0063] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 190 bar and a temperature of 60°C to obtain a homogenized liquid.

[0064] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 65℃, and the sterilization time is 35 minutes to obtain the liquid after first pasteurization.

[0065] (9) Inoculation: The liquid after the first pasteurization is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0066] (10) Fermentation: The inoculated liquid is fermented for 5 hours at a temperature of 30°C to obtain the fermented liquid.

[0067] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.07 g / 100 g to obtain the liquid after adding auxiliary materials;

[0068] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 65°C for 35 minutes to obtain the feed solution after the second pasteurization.

[0069] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0070] Example 3:

[0071] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0072] (1) Provide raw milk;

[0073] (2) Deaeration: The liquid obtained after cleaning raw milk is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 barr to obtain the deaerated liquid.

[0074] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0075] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0076] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0077] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0078] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0079] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 72℃, and the sterilization time is 12 seconds to obtain the liquid after first pasteurization.

[0080] (9) Inoculation: The liquid after the first pasteurization is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0081] (10) Fermentation: The liquid treated in step (9) is fermented for 6 hours at a temperature of 28°C to obtain the fermented liquid.

[0082] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.08 g / 100 g to obtain the liquid after adding auxiliary materials;

[0083] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 72°C for 12 seconds to obtain the feed solution after the second pasteurization.

[0084] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0085] Example 4:

[0086] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0087] (1) Provide raw milk;

[0088] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 bar to obtain the deaerated liquid.

[0089] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0090] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0091] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0092] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0093] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0094] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 75℃, and the sterilization time is 15 seconds to obtain the liquid after first pasteurization.

[0095] (9) Inoculation: The pasteurized liquid is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0096] (10) Fermentation: The inoculated liquid is fermented for 6 hours at a temperature of 28°C to obtain the fermented liquid.

[0097] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.08 g / 100 g to obtain the liquid after adding auxiliary materials;

[0098] (12) Second pasteurization: The liquid with added excipients is pasteurized for the second time at 75°C for 15 seconds to obtain the liquid after the second pasteurization.

[0099] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0100] Comparative Example 1:

[0101] This comparative example provides a type of milk, the preparation method of which is as follows:

[0102] (1) Provide raw milk;

[0103] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 55℃ and a deaeration pressure of -0.09 bar to obtain the deaerated liquid.

[0104] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0105] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 50°C and a centrifuge speed of 5000 rpm to obtain skim milk that has undergone physical sterilization.

[0106] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 121°C for 4 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain light cream that has been sterilized at high temperature.

[0107] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0108] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 170 bar and a temperature of 50°C to obtain a homogenized liquid.

[0109] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 62℃, and the sterilization time is 25 minutes to obtain the liquid after first pasteurization.

[0110] (9) Inoculation: The pasteurized liquid is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0111] (10) Fermentation: The inoculated liquid is fermented for 6 hours at a temperature of 40°C to obtain the fermented liquid.

[0112] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.06 g / 100 g to obtain the liquid after adding auxiliary materials;

[0113] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 62°C for 25 minutes to obtain the feed solution after the second pasteurization.

[0114] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0115] Comparative Example 2:

[0116] This comparative example provides a type of milk, the preparation method of which is as follows:

[0117] (1) Provide raw milk;

[0118] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 60°C and a deaeration pressure of -0.07 bar to obtain the deaerated liquid.

[0119] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0120] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 55°C and a centrifuge speed of 7000 rpm to obtain skim milk that has undergone physical sterilization.

[0121] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 130°C for 3 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0122] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0123] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 190 bar and a temperature of 60°C to obtain a homogenized liquid.

[0124] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 65℃, and the sterilization time is 35 minutes to obtain the liquid after first pasteurization.

[0125] (9) Inoculation: The liquid after the first pasteurization is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0126] (10) Fermentation: The inoculated liquid is fermented for 4 hours at a temperature of 32°C to obtain the fermented liquid.

[0127] (11) Second pasteurization: The fermented liquid is pasteurized at 65°C for 35 minutes to obtain the second pasteurized liquid.

[0128] (12) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0129] Comparative Example 3:

[0130] This comparative example provides a type of milk, the preparation method of which is as follows:

[0131] (1) Provide raw milk;

[0132] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 bar to obtain the deaerated liquid.

[0133] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0134] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0135] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0136] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0137] (7) Homogenization: The degassed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0138] (8) Pasteurization: The homogenized liquid is pasteurized indirectly at a temperature of 72°C for 12 seconds to obtain the pasteurized liquid.

[0139] (9) Inoculation: The pasteurized liquid is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0140] (10) Fermentation: The inoculated liquid is fermented for 4 hours at a temperature of 32°C to obtain the fermented liquid.

[0141] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.06 g / 100 g to obtain the liquid after adding auxiliary materials;

[0142] (12) Filling: Cool the liquid after adding auxiliary materials to 4°C and fill it. The extended fermentation time of the liquid is the time from the second pasteurization time to the time before filling.

[0143] Comparative Example 4:

[0144] This comparative example provides a type of milk, the preparation method of which is as follows:

[0145] (1) Provide raw milk;

[0146] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 bar to obtain the deaerated liquid.

[0147] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0148] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0149] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0150] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0151] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0152] (8) Pasteurization: The homogenized liquid is pasteurized indirectly at a temperature of 75°C for 15 seconds to obtain pasteurized liquid.

[0153] (9) Filling: Cool the pasteurized liquid to 4°C and fill it.

[0154] Comparative Example 5:

[0155] This comparative example provides a type of milk, the preparation method of which is as follows:

[0156] (1) Provide raw milk;

[0157] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 60°C and a deaeration pressure of -0.07 bar to obtain the deaerated liquid.

[0158] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0159] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 55°C and a centrifuge speed of 7000 rpm to obtain skim milk that has undergone physical sterilization.

[0160] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 130°C for 3 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain skim milk and light cream.

[0161] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0162] (7) Homogenization: The degassed liquid is homogenized in a sterile environment at a pressure of 30 / 190 bar and a temperature of 60°C to obtain a homogenized liquid.

[0163] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 65℃, and the sterilization time is 35 minutes to obtain the liquid after first pasteurization.

[0164] (9) Inoculation: The liquid after the first pasteurization is inoculated with fermentation strain XPL-40. When the temperature of the liquid drops to 30-40℃, Lactococcus lactis XPL-40 from Chr. Hansen (Beijing) Trading Co., Ltd. is mixed into the liquid and stirred evenly. The amount added is 2.16g / 100kg.

[0165] (10) Fermentation: The liquid treated in step (9) is fermented for 4 hours at a temperature of 32°C to obtain the fermented liquid.

[0166] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.06 g / 100 g to obtain the liquid after adding auxiliary materials;

[0167] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 65°C for 35 minutes to obtain the feed solution after the second pasteurization.

[0168] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0169] Comparative Example 6:

[0170] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0171] (1) Provide raw milk;

[0172] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 bar to obtain the deaerated liquid.

[0173] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0174] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0175] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0176] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0177] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0178] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 75℃, and the sterilization time is 15 seconds to obtain the liquid after first pasteurization.

[0179] (9) Inoculation: The pasteurized liquid is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0180] (10) Fermentation: The inoculated liquid is fermented for 6 hours at a temperature of 28°C to obtain the fermented liquid.

[0181] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.2 g / 100 g to obtain the liquid after adding auxiliary materials;

[0182] (12) Second pasteurization: The liquid with added excipients is pasteurized for the second time at 75°C for 15 seconds to obtain the liquid after the second pasteurization.

[0183] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0184] Comparative Example 7:

[0185] This embodiment provides a lightly fermented, buttery-flavored milk, the preparation method of which is as follows:

[0186] (1) Provide raw milk;

[0187] (2) Deaeration: The raw milk liquid obtained after purification is deaerated at a temperature of 65℃ and a deaeration pressure of -0.04 bar to obtain the deaerated liquid.

[0188] (3) Fat-milk separation: The degassed liquid is preheated to 55-65℃ and centrifuged to obtain skim milk and light cream.

[0189] (4) Physical sterilization: The skim milk is physically sterilized using a sterilization separator at a temperature of 60°C and a centrifuge speed of 10,000 rpm to obtain skim milk that has undergone physical sterilization.

[0190] (5) High-temperature sterilization of light cream: The separated light cream is sterilized at a temperature of 132°C for 2 seconds. After sterilization, the temperature of the light cream is reduced to 40°C to obtain high-temperature sterilized light cream.

[0191] (6) Online mixing: Skim milk that has undergone physical sterilization and light cream that has undergone high temperature sterilization are mixed online to obtain a mixed liquid;

[0192] (7) Homogenization: The mixed liquid is homogenized in a sterile environment at a pressure of 30 / 220 bar and a temperature of 65°C to obtain a homogenized liquid.

[0193] (8) First pasteurization: The homogenized liquid is subjected to first pasteurization. The sterilization method is indirect sterilization, the sterilization temperature is 75℃, and the sterilization time is 15 seconds to obtain the liquid after first pasteurization.

[0194] (9) Inoculation: The pasteurized liquid is inoculated with fermentation bacteria. When the temperature of the liquid drops to 30-40℃, the fermentation bacteria are Lactococcus lactis from Danisco (China) Co., Ltd. BT01LYO was mixed into the feed solution and stirred evenly. The addition amount was 2.16g / 100kg to obtain the feed solution after inoculation.

[0195] (10) Fermentation: The inoculated liquid is fermented for 6 hours at a temperature of 28°C to obtain the fermented liquid.

[0196] (11) Adding auxiliary materials: Add sodium chloride to the fermented liquid at a rate of 0.06 g / 100 g to obtain the liquid after adding auxiliary materials;

[0197] (12) Second pasteurization: The feed solution with added excipients is pasteurized for the second time at 75°C for 10 minutes to obtain the feed solution after the second pasteurization.

[0198] (13) Filling: Cool the liquid after the second sterilization to 4°C and fill it.

[0199] Product performance test results:

[0200] Table 1

[0201]

[0202] Table 2

[0203] Cheese flavor sourness Preference Example 1 7.8 4.2 7.5 Example 2 8.4 4.3 7.5 Example 3 8.6 4.6 7.6 Example 4 8.5 4.6 7.8 Comparative Example 1 7.8 8.5 3.1 Comparative Example 2 3.1 6.8 3.6 Comparative Example 3 7.5 7.5 3.3 Comparative Example 4 0 3.8 7.0 Comparative Example 5 4.3 7.0 3.8 Comparative Example 6 3.5 4.6 3.9 Comparative Example 7 6.6 5.5 5.8

[0204] The taste and flavor scoring criteria for milk are shown in Table 1. The test involved 30 people. Nine milk samples were placed in front of each person. Each person tasted each sample in turn. Between tasting any two samples, each person rinsed their mouth with water for 30 seconds to remove the taste of the previous sample. After tasting, each person scored the samples according to Table 1. The average score of the samples was taken as the final result. As can be seen from the flavor evaluation table in Table 2, the milk obtained by adding microbial strains, setting specific fermentation parameters, adding sodium chloride, and adding other fermentation strains, compared to Comparative Example 4, all in Examples 1-4 effectively imparted a cheese aroma and improved the taste. Comparative Example 1, due to excessively high fermentation temperature and prolonged fermentation time, resulted in over-fermentation of the microbial strains, producing a large amount of aroma substances, leading to an overly strong cheese aroma that severely impacted the taste. Comparative Example 2, without the addition of sodium chloride, could not further release its cheese aroma, weakening the taste. Comparative Example 3, without secondary pasteurization, continued fermentation produced a large amount of aroma substances, resulting in an overly strong cheese aroma that severely impacted the taste. Comparative Example 5, without using specific microbial strains, resulted in excessive acid production, affecting the flavor. Unsuitable fermentation strains, fermentation parameters, adding inappropriate proportions of sodium chloride, and unsuitable sterilization processes can all affect the cheese aroma content.

[0205] Regarding acidity, using the same batch of raw milk, selecting specific fermentation temperatures and times for different strains, along with the addition of sodium chloride, resulted in a significant improvement in acidity. This is because fermenting at lower temperatures for longer periods reduces the logarithmic growth rate of the bacteria, thus decreasing the amount of post-acidity produced. Furthermore, with specific fermentation strains and parameters, and the addition of sodium chloride, the examples demonstrated a better reduction in fermentation-induced acidity and produced more cheesy flavor compounds compared to the comparative examples. In terms of preference, the level of preference is primarily related to the ratio of cheesy flavor to acidity (excluding raw milk). Examples 1-4 showed significantly higher preference than comparative examples 1-3 and 5-7.

[0206] Table 3

[0207] sample pH Acidity / °T Example 1 6.54 18.0 Example 2 6.43 19.2 Example 3 6.38 24.8 Example 4 6.38 24.7 Comparative Example 1 4.81 65.5 Comparative Example 2 5.35 46.0 Comparative Example 3 5.02 50.1 Comparative Example 4 6.61 16.2 Comparative Example 5 5.20 48.8 Comparative Example 6 6.60 17.2 Comparative Example 7 6.38 24.5

[0208] The pH and acidity measurement results of the samples are shown in Table 3. As can be seen from Table 3, the pH of Examples 1-4 was between 6.38 and 6.54, and the acidity was between 18.0 and 24.8°T. In contrast, the pH of Comparative Examples 1-3 and Comparative Examples 5-7 was between 4.81 and 5.35, and the acidity was between 46.0 and 65.5°T. Compared with Examples 1-4, the pH of Comparative Examples 1-3 and Comparative Examples 5-7 was significantly lower, and the acidity was significantly higher. The fermentation temperature of Comparative Example 1 was too high, and the fermentation time was too long. The strain over-fermented and produced a large amount of lactic acid, resulting in increased acidity. Comparative Example 2 used only the strain, but without the addition of sodium chloride, it could not achieve the effect of reducing acidity. Comparative Example 3 did not undergo secondary pasteurization, and the strain continued to ferment and produce excess lactic acid, which also increased acidity. Comparative Example 5 used other strains and added sodium chloride, but it could not achieve the effect of reducing acidity.

[0209] Table 4

[0210]

[0211]

[0212] The aroma and flavor results of the examples and comparative examples are shown in Table 4. As can be seen from Table 4, comparative example 4 only has its own milky aroma, while examples 1-4 all have a rich milky and cheese aroma. However, comparative example 1, due to the lack of specific fermentation parameters, has an overly strong fermentation flavor and obvious sourness. Comparative example 2, due to the lack of a sodium chloride addition step, has no cheese aroma and obvious sourness. Comparative example 3, due to the lack of a secondary pasteurization step, has a continuously producing acid by the bacteria, resulting in an overly strong fermentation flavor and obvious sourness. Comparative example 5, due to the lack of specific fermentation bacteria, still has obvious sourness even with the addition of sodium chloride. Comparative example 6 added excessive sodium chloride. Comparative example 7, with its extended secondary pasteurization time, will affect the saltiness and cooked taste, thus affecting the sample's liking.

[0213] Table 5

[0214]

[0215] The physicochemical content results of the examples and comparative examples are shown in Table 5. As can be seen from Table 5, compared with the comparative examples, the fermentation time of Examples 1-4 was shorter, the fermentation temperature was lower, and the lactose content was relatively higher. The sodium content increased after the addition of sodium chloride. The overall protein content was not significantly different from that of Comparative Examples 1-5. Comparative Example 1 did not select specific fermentation parameters, and the fermentation time was longer and the fermentation temperature was higher. Therefore, the lactic acid bacteria grew faster and consumed more lactose. Comparative Example 3 did not undergo secondary pasteurization, and the lactic acid bacteria continued to grow, also consuming more lactose.

[0216] Table 6

[0217] sample Viscosity (mPa·s) elasticity Hardness / g Example 1 25 0.07 30 Example 2 25 0.06 31 Example 3 25 0.08 31 Example 4 30 0.11 31 Comparative Example 1 400 0.45 32 Comparative Example 2 650 0.51 135 Comparative Example 3 450 0.48 130 Comparative Example 4 30 0.05 30 Comparative Example 5 350 0.44 128 Comparative Example 6 55 0.05 31 Comparative Example 7 200 0.18 55

[0218] The viscosity test results of the examples and comparative examples are shown in Table 6. As can be seen from Table 6, the viscosity of Examples 1-4 is significantly lower than that of the comparative examples. There is no significant difference in viscosity between Examples 1-4 and Comparative Example 4. Comparative Examples 1-3 and Comparative Example 5 did not select specific fermentation conditions, did not use specific strains of bacteria for fermentation, and did not add sodium chloride. Comparative Example 7 did not select specific secondary pasteurization parameters, which led to an increase in viscosity of Comparative Examples 1-3, Comparative Example 5, and Comparative Example 7. The elasticity of Comparative Examples 1-3, Comparative Example 5, and Comparative Example 7 increased, and the hardness of Comparative Examples 2, Comparative Example 3, and Comparative Example 5 increased. This indicates that the milk structure has changed and has an adverse effect on flavor and taste.

Claims

1. A lightly fermented, buttery-flavored milk, wherein, This lightly fermented buttery milk meets the following requirements: Milk protein content ≤ 3.6g / 100g ≤ 3.8g / 100g; 4.5g / 100g ≤ lactose ≤ 5.5g / 100g; 18°T ≤ Acidity ≤ 25°T.

2. The lightly fermented buttery milk according to claim 1, wherein, The lightly fermented buttery milk also meets the following requirements: 115mg / 100g ≤ Sodium ≤ 120mg / 100g; 120mg / 100g≤Natural calcium≤130mg / 100g.

3. The method for preparing lightly fermented cheese-flavored milk according to claim 1, wherein, The preparation method includes a step of fermenting the pasteurized liquid, and a step of adding excipients after fermentation; The fermentation process uses a combination of three types of Lactococcus lactis, including Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis fat, and Lactococcus lactis fat diacetyl. The auxiliary material is sodium chloride, and the addition amount is 0.06-0.08g / 100g. This addition amount is based on the total mass of the fermented liquid, and the liquid after adding the auxiliary material is obtained.

4. The preparation method according to claim 3, wherein, The preparation method includes the following steps: degassing, separating fat and milk, sterilizing, mixing and homogenizing, first pasteurization, fermentation, adding auxiliary materials, and second pasteurization of the liquid obtained after cleaning raw milk.

5. The preparation method according to claim 4, wherein, The degassing process includes the following steps: degassing the liquid obtained after cleaning raw milk at a temperature of 55-65℃ and a degassing pressure of -0.04 to -0.09 bar to obtain the degassed liquid.

6. The preparation method according to claim 4 or 5, wherein, The fat-milk separation includes the following steps: preheating the degassed liquid to 55-65°C and centrifuging it to obtain skim milk and cream.

7. The preparation method according to claim 4 or 6, wherein, The sterilization process includes the following steps: using a sterilization separator to physically sterilize skim milk at a temperature of 50-60℃ and a centrifuge speed of 5000-10000 rpm to obtain skim milk after physical sterilization; and sterilizing light cream at a high temperature of 121-132℃ for 1-15 seconds, and then lowering the temperature of the light cream to 30-55℃ after sterilization to obtain light cream after high-temperature sterilization.

8. The preparation method according to claim 4 or 7, wherein, The mixing and homogenization includes the following steps: skim milk that has undergone physical sterilization and light cream that has undergone high-temperature sterilization are mixed online to obtain a mixed liquid. The mixed liquid is then homogenized in a sterile environment at a homogenization pressure of 30 / 170-220 bar and a homogenization temperature of 50-65°C to obtain a homogenized liquid.

9. The preparation method according to claim 4 or 8, wherein, The first pasteurization includes the following steps: the homogenized liquid is indirectly pasteurized at a temperature of 62-65℃ for 25-35 minutes, or at a temperature of 72-75℃ for 12-15 seconds, using plate pasteurization or tubular pasteurization, to obtain the first pasteurized liquid.

10. The preparation method according to claim 4 or 9, wherein, The fermentation includes the following steps: cooling the pasteurized liquid to 30-40℃, mixing the inoculum into the liquid and stirring evenly, with an addition amount of 2.1-2.2g / 100kg to obtain the inoculated liquid, and fermenting the inoculated liquid for 4-6 hours at a temperature of 28-32℃ to obtain the fermented liquid.

11. The preparation method according to claim 4, wherein, The second pasteurization includes the following steps: pasteurizing the feed liquid after adding excipients a second time, with a pasteurization temperature of 62-65℃ and a pasteurization time of 25-35 minutes, or a pasteurization temperature of 72-75℃ and a pasteurization time of 12-15 seconds, and the pasteurization method is plate pasteurization or tube pasteurization, to obtain lightly fermented cheese-flavored milk.

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