Brown lactic acid bacteria drink and method for preparing the same

Abstract

The present application belongs to the technical field of lactic acid bacteria beverage, and particularly relates to a brown lactic acid bacteria beverage and a preparation method thereof. The preparation method of the brown lactic acid bacteria beverage adopts a processing sequence of raw material dissolution- pasteurization- fermentation- blending- browning- acidification- filling, that is, corresponding browning and acidification steps are carried out after fermentation, i.e. blending of ingredients, so that the production efficiency of the lactic acid bacteria beverage is effectively improved, the Maillard flavor of the product is ensured, and the lactic acid bacteria product has the advantages of stable properties and better taste.

Description

Technical Field

[0001] This invention belongs to the field of lactic acid bacteria beverage technology, specifically relating to a brown lactic acid bacteria beverage, and further disclosing its preparation method. Background Technology

[0002] Currently, commercially available brown lactic acid bacteria drinks such as Yakult and Yoyi C are popular with consumers due to their unique Maillard reaction color and flavor, rich yogurt fermentation flavor, and relatively healthy zero-fat image. Brown lactic acid bacteria drinks are produced by adding reducing sugars to reconstituted milk and then browning it at high temperatures, giving the product its unique Maillard flavor. However, due to the specific conditions required for the Maillard reaction, achieving the desired color range in the production of lactic acid bacteria drinks requires a relatively long browning reaction time. Furthermore, to achieve the unique fermented flavor of lactic acid bacteria products, traditional brown lactic acid bacteria drinks typically use *Lactobacillus paracasei* for fermentation. However, *Lactobacillus paracasei* has significant limitations in its acid production rate; reaching the required acidity level for lactic acid bacteria drinks requires 65-72 hours of fermentation, resulting in a long production cycle.

[0003] For example, Chinese patent CN102499285A discloses a high-fiber, sugar-free brown active lactic acid bacteria beverage. This high-fiber, low-sugar brown active lactic acid bacteria beverage improves upon existing brown active lactic acid bacteria beverages by adding a higher content of dietary fiber to enhance its added value. Furthermore, it reduces the sucrose content while maintaining good flavor and texture, and avoids water separation, sedimentation, and stratification by adding a high-sweetness sweetener to partially replace sucrose and by constructing a reasonable product stabilization system. Another example is the study by Du Yu et al. on the stability of lactic acid bacteria beverages, exploring the effects of stabilizers on the stability of these beverages. They evaluated the stability of different ratios of pectin, sodium carboxymethyl cellulose, xanthan gum, and guar gum using orthogonal experiments. However, this product involves a large number of stabilizers, leading to complex formulation processes. Additionally, the use of multiple stabilizers results in unclean product labels, potentially causing consumer resistance. For example, Chinese patent CN104304451A discloses a stabilizer for brown lactic acid bacteria beverages and a sterilized brown lactic acid bacteria beverage. Based on a stabilizer system of pectin, sodium carboxymethyl cellulose, soybean polysaccharide, microcrystalline cellulose, and gellan gum, it effectively prevents undesirable phenomena such as water separation, sedimentation, flocculation, and stratification in the lactic acid bacteria beverage. Within a 6-month shelf life, the sterilized brown lactic acid bacteria beverage exhibits a uniform and stable state, without flocculation, stratification, or significant sedimentation, and has a refreshing and full-bodied taste. It is evident that while the above-mentioned lactic acid bacteria beverages effectively improve product performance through adjustments to the product system, they still cannot solve the problems of long fermentation cycles and prolonged browning times in lactic acid bacteria products. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a brown lactic acid bacteria beverage, which has a rich Maillard flavor and yogurt flavor, and has better product stability.

[0005] The second technical problem to be solved by the present invention is to provide a method for preparing the brown lactic acid bacteria beverage by rapid fermentation.

[0006] To solve the above-mentioned technical problems, the present invention provides a method for preparing a brown lactic acid bacteria beverage, comprising the following steps:

[0007] (1) Take defatted powder and add water to make ingredients, sterilize it to obtain fermentation base material, add fermentation agent to the fermentation base material, and ferment and demulsify to obtain fermented milk for later use;

[0008] (2) Add stabilizers and reducing sugars to the fermented milk and mix and homogenize to obtain milk base material;

[0009] (3) The milk base material is subjected to ultra-high temperature sterilization and browning treatment, and the resulting brown milk is acidified and filled.

[0010] Specifically, step (1) further includes the step of adding lactose hydrolase to the fermentation substrate;

[0011] Preferably, the total amount of the fermentation base includes: 10-13 wt% defatted powder, 0.1-0.3 wt% lactose hydrolase, and water to make up to 100%.

[0012] Specifically, in step (1), the fermentation agent includes a mixed agent of Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei;

[0013] Preferably, the mass ratio of Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei is 1:1-3:1-3, and more preferably, the ratio is 1:2:2.

[0014] Preferably, the amount of the fermentation agent is 0.3-0.8 U / kg based on the amount of the fermentation substrate.

[0015] Specifically, in step (1):

[0016] The fermentation step is carried out at a temperature of 43±1℃, and the final control of the fermentation step is a pH value of 3.6-4.0 and an acidity of 140-160; and / or,

[0017] The sterilization step is performed at a temperature of 85±2℃ for a sterilization time of 300±20s; and / or,

[0018] The stirring speed for the demulsification step is 30-50 r / min, and the demulsification time is 15 min; and / or,

[0019] The ingredient preparation step further includes a step of preheating water to 45-55°C before preparation; and / or,

[0020] The ingredient preparation step is followed by a hydration treatment step, preferably a step of standing hydration at 45-55°C for 30-40 minutes.

[0021] Specifically, in step (1), during the fermentation step, after 10 hours of fermentation, samples are taken to observe and measure the acidity and pH value of the product. If the product has formed a good gel structure, with a smooth and flat mirror surface, and the pH value is between 3.6 and 4.0, and the acidity is between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0022] Specifically, in step (2):

[0023] The stabilizer includes one or a mixture of several of soybean polysaccharides and pectin; and / or,

[0024] The reducing sugar includes one or a mixture of several of arabinose or sucralose.

[0025] Specifically, in step (2), the temperature of the homogenization step is 95-98℃, and the homogenization pressure is 40-200 bar; and / or,

[0026] In step (2), the temperature of the mixing step is 30-40℃; and / or,

[0027] Step (2) further includes the step of adding water to the stabilizer to form a soluble mixture, preferably at a temperature of 60-70°C.

[0028] Preferably, in the step of adding water to the stabilizer, the amount of water added is 30 times the amount of stabilizer used.

[0029] Specifically, in step (3), the temperature of the ultra-high temperature sterilization and browning treatment step is 147-157℃, and the time is 9-15 seconds; and / or,

[0030] In step (3), the acid adjustment step includes a sterile online acid adjustment step, and preferably, the acid agent in the acid adjustment step includes citric acid.

[0031] In step (3), the ultra-high temperature sterilization and browning treatment step is preferably performed until the solution reaches about 750°C (Pantone color chart).

[0032] In step (3), the acid adjustment step uses a sterile online acid adjustment system to add the prepared citric acid solution online to adjust the acidity of the system and keep the acidity of the final product between 38-42°T.

[0033] In step (3), the filling step adopts aseptic cold filling technology, that is, aseptic filling is carried out at 20-25℃, nitrogen concentration is 99.99%, nitrogen pressure is 1.5±0.2 bar, and nitrogen flow rate is 1.5±0.2 slm.

[0034] Specifically, the preparation method of the brown lactic acid bacteria beverage includes the following components in terms of mass content, based on the total amount of raw materials: 18-20 wt% fermented milk, 0.3-0.6 wt% stabilizer, 4.008-6.012 wt% reducing sugar, 0.1-0.2 wt% citric acid, and water added to make up to 100%.

[0035] Specifically, the preparation method of the brown lactic acid bacteria beverage includes the following components by mass content, based on the total amount of raw materials: 18-20 wt% fermented milk, 0.2-0.4 wt% soybean polysaccharide, 0.1-0.2 wt% pectin, 4-6 wt% arabinose, 0.008-0.012 wt% sucralose, and 0.1-0.2 wt% citric acid, with water added to make up to 100%.

[0036] The present invention also discloses a brown lactic acid bacteria beverage prepared by the method described above.

[0037] The preparation method of the brown lactic acid bacteria beverage of the present invention adopts the processing sequence of raw material dissolution-pasteurization-fermentation-blending-browning-acidification-bottling. That is, the corresponding browning and acidification steps are carried out after fermentation, i.e., ingredient preparation. Compared with the traditional brown lactic acid bacteria beverage processing technology, which involves raw material dissolution-heating-browning-fermentation-blending-sterilization-bottling (i.e., browning is carried out before fermentation), the preparation method of the brown lactic acid bacteria beverage of the present invention has the following advantages:

[0038] (1) Different production efficiencies (shown in production time): Traditional lactic acid bacteria beverages undergo pre-browning. To achieve the final product color, the color needs to be deepened as much as possible during pre-browning (Pantone color chart 720C-721C), with a browning time of 3-4 hours (95-97℃), and also requires a long-term low-temperature fermentation of about 65-72 hours. However, the preparation method of the lactic acid bacteria beverage described in this invention, through ultra-high temperature sterilization and browning followed by acid adjustment, can quickly induce the Maillard reaction. Since the finished product requires a lighter color, browning is carried out after the second batch of ingredients. This invention can shorten the original browning time by 1-2 hours to achieve the desired color, allowing the Maillard reaction to occur rapidly and flavor compounds to be retained to a greater extent. Furthermore, the post-browning method shortens the browning time to the target color of the finished product (9-15 seconds), significantly improving production efficiency. Compared with traditional lactic acid bacteria production methods, the method described in this invention can reduce the time of nearly 50 hours, including the time for fermentation, aroma production, heating, cooling, and browning processes. Moreover, homogenization can be performed directly after browning, reducing the production cost of heating before homogenization and greatly improving production efficiency.

[0039] (2) The Maillard flavor is different (as reflected in the flavor evaluation). The traditional preparation method of lactic acid bacteria beverage is the pre-browning method, which leads to the loss of Maillard flavor substances after fermentation. However, the preparation method of this invention adopts the method of fermentation first and then browning. The Maillard flavor is obtained by browning after fermentation (i.e. after the second ingredient addition), so that the Maillard flavor is not affected by fermentation and the loss of Maillard flavor is small. It can ensure a more complete Maillard browning flavor and yogurt fermentation flavor. Moreover, the product can achieve a good flavor without the need to add flavoring or flavor enhancement or add glucose and sucrose, and obtain a rich Maillard flavor and yogurt flavor.

[0040] (3) Stability (as shown by centrifugal sedimentation rate): In the traditional preparation of lactic acid bacteria beverages, the protein components and reducing sugars need to be heated together for a long time for a high-temperature Maillard reaction (i.e., browning process). During this process, the protein is very prone to aggregation and precipitation. However, the preparation method of lactic acid bacteria beverages described in this invention carries out the Maillard reaction after formulation, which effectively reduces the exposure time of the protein in a high-temperature environment and improves the stability of the beverage to a certain extent.

[0041] (4) Product particle size (shown by particle size analyzer results): Since the traditional preparation method of lactic acid bacteria beverage is browning before fermentation, in order to achieve the color requirements of the final product, the color needs to be deepened as much as possible during the pre-browning process, resulting in a browning time of up to 2-3 hours; however, the preparation method of lactic acid bacteria beverage described in this invention uses ultra-high temperature sterilization, which completes the browning process simultaneously during sterilization, and can reach the expected color endpoint in a very short time (9-15s). Since the protein is heated for a shorter time, the phenomenon of protein molecules agglomerating due to heat is effectively reduced, thereby reducing the product particle size and improving the stability to a certain extent, thus enhancing the product drinking experience.

[0042] (5) The method for preparing lactic acid bacteria beverage according to the present invention, in the fermentation process of fermented milk, by adding lactose hydrolase to the formula to decompose lactose into galactose and glucose, can be quickly utilized by Streptococcus thermophilus and Lactobacillus bulgaricus, accelerate the reproduction of fermentation strains and decompose proteins into amino acids, effectively accelerate the utilization of Lactobacillus paracasei and the production of flavor substances; at the same time, the galactose and glucose in the system that are not fully utilized can further participate in the Maillard reaction, accelerate color change and the accumulation of Maillard flavor substances; and the use of a mixed inoculum of Streptococcus thermophilus, Lactobacillus bulgaricus and Lactobacillus paracasei for fermentation, compared with the traditional lactic acid bacteria beverage prepared by Lactobacillus paracasei, can effectively save more fermentation time and improve production efficiency;

[0043] (6) The preparation method of the lactic acid bacteria beverage of the present invention, by adjusting the formula, uses soybean polysaccharide and pectin as a stabilizing system, and adds pentose reducing sugars such as arabinose that undergo Maillard reaction more quickly. The residual galactose, glucose and pentose in the system are heated with the protein in an ultra-high temperature environment, which effectively reduces the exposure time of the protein in a high temperature environment and improves the stability of the beverage to a certain extent. This method can save time and production costs, the Maillard flavor is completely preserved and is less affected by fermentation, no flavoring is required, and the finished product has uniform particle size and good stability, and can also achieve the product claim of zero sugar and zero fat.

[0044] (7) In the preparation method of the lactic acid bacteria beverage of the present invention, it is preferable to add arabinose. Clinical trials have shown that L-arabinose has an inhibitory effect on the metabolic conversion of sucrose, making it promising for application in weight loss, diabetes control, etc. The American Medical Association also lists L-arabinose as a nutritional supplement or over-the-counter drug for anti-obesity agents. In 2008, the Ministry of Health of my country approved L-arabinose as a new resource food in Announcement No. 12, with the scope of use being "all kinds of food, but excluding infant food". It can rapidly undergo Maillard reaction with amino acids under suitable temperature conditions, and its reaction rate is greater than that of glucose, sucrose, and erythritol, further ensuring the high efficiency of browning and flavor requirements of the lactic acid bacteria beverage of the present invention. Attached Figure Description

[0045] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0046] Figure 1 This is a process flow diagram of the brown lactic acid bacteria beverage described in this invention. Detailed Implementation

[0047] In the following embodiments of the present invention, the selected defatting powder was tested according to GB 19644, and it can be used after passing the test.

[0048] Example 1

[0049] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0050] (1) Preparation of fermented milk

[0051] Accurately weigh defatted powder at a ratio of 12 wt%, and weigh lactose hydrolase at a ratio of 0.2 wt%. Preheat the water for mixing to 50°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 40 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 50°C for 35 minutes to hydrate, and then pasteurize at 85°C for 300 seconds.

[0052] After sterilization, the fermentation substrate is cooled to 43°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.5 U / kg of fermentation substrate. The fermentation temperature is controlled at 43°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0053] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 40 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0054] (2) Secondary batching

[0055] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components by mass: 19 wt% fermented milk, 0.3 wt% soybean polysaccharide, 0.15 wt% pectin, 4 wt% arabinose, 0.01 wt% sucralose, 0.15 wt% citric acid, and water to make up to 100%.

[0056] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 30 times their weight of hot water at 65°C. Stir at 25 rpm for 20 minutes. When the stabilizer mixture cools to 35°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 25 rpm for 15 minutes. Then, homogenize at 96°C and 100 bar to obtain the milk base material.

[0057] (3) Ultra-high temperature sterilization browning

[0058] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 157°C for 12 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0059] Example 2

[0060] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0061] (1) Preparation of fermented milk

[0062] Accurately weigh defatted powder at a ratio of 12 wt%, and weigh lactose hydrolase at a ratio of 0.2 wt%. Preheat the water for mixing to 50°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 40 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 50°C for 35 minutes to hydrate, and then pasteurize at 85°C for 300 seconds.

[0063] After sterilization, the fermentation substrate is cooled to 43°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.5 U / kg of fermentation substrate. The fermentation temperature is controlled at 43°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0064] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 40 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0065] (2) Secondary batching

[0066] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components by mass: 19 wt% fermented milk, 0.3 wt% soybean polysaccharide, 0.15 wt% pectin, 6 wt% arabinose, 0.01 wt% sucralose, 0.15 wt% citric acid, and water to make up to 100%.

[0067] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 30 times their weight of hot water at 65°C. Stir at 25 rpm for 20 minutes. When the stabilizer mixture cools to 35°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 25 rpm for 15 minutes. Then, homogenize at 96°C and 100 bar to obtain the milk base material.

[0068] (3) Ultra-high temperature sterilization browning

[0069] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 157°C for 12 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0070] Example 3

[0071] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0072] (1) Preparation of fermented milk

[0073] Accurately weigh defatted powder at a ratio of 12 wt%, and weigh lactose hydrolase at a ratio of 0.2 wt%. Preheat the water for mixing to 50°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 40 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 50°C for 35 minutes to hydrate, and then pasteurize at 85°C for 300 seconds.

[0074] After sterilization, the fermentation substrate is cooled to 43°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.5 U / kg of fermentation substrate. The fermentation temperature is controlled at 43°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0075] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 40 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0076] (2) Secondary batching

[0077] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components by mass: 19 wt% fermented milk, 0.3 wt% soybean polysaccharide, 0.15 wt% pectin, 4 wt% arabinose, 0.01 wt% sucralose, 0.15 wt% citric acid, and water to make up to 100%.

[0078] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 30 times their weight of hot water at 65°C. Stir at 25 rpm for 20 minutes. When the stabilizer mixture cools to 35°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 25 rpm for 15 minutes. Then, homogenize at 96°C and 100 bar to obtain the milk base material.

[0079] (3) Ultra-high temperature sterilization browning

[0080] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 157°C for 15 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0081] Example 4

[0082] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0083] (1) Preparation of fermented milk

[0084] Accurately weigh defatted powder at a ratio of 12 wt%, and weigh lactose hydrolase at a ratio of 0.2 wt%. Preheat the water for mixing to 50°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 40 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 50°C for 35 minutes to hydrate, and then pasteurize at 85°C for 300 seconds.

[0085] After sterilization, the fermentation substrate is cooled to 43°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.5 U / kg of fermentation substrate. The fermentation temperature is controlled at 43°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0086] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 40 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0087] (2) Secondary batching

[0088] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components by mass: 19 wt% fermented milk, 0.3 wt% soybean polysaccharide, 0.15 wt% pectin, 4 wt% arabinose, 0.01 wt% sucralose, 0.15 wt% citric acid, and water to make up to 100%.

[0089] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 30 times their weight of hot water at 65°C. Stir at 25 rpm for 20 minutes. When the stabilizer mixture cools to 35°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 25 rpm for 15 minutes. Then, homogenize at 96°C and 100 bar to obtain the milk base material.

[0090] (3) Ultra-high temperature sterilization browning

[0091] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 157°C for 9 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0092] Example 5

[0093] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0094] (1) Preparation of fermented milk

[0095] Accurately weigh defatted powder at a ratio of 10 wt%, and weigh lactose hydrolase at a ratio of 0.1 wt%. Preheat the water for mixing to 45°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 30 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 45°C for 30 minutes to hydrate, and then pasteurize at 83°C for 300 seconds.

[0096] After sterilization, the fermentation substrate is cooled to 42°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.3 U / kg of fermentation substrate. The fermentation temperature is controlled at 42°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0097] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 30 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0098] (2) Secondary batching

[0099] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components by mass: 18 wt% fermented milk, 0.4 wt% soybean polysaccharide, 0.1 wt% pectin, 5 wt% arabinose, 0.008 wt% sucralose, 0.2 wt% citric acid, and water to make up to 100%.

[0100] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 30 times their weight of hot water at 60°C. Stir at 20 rpm for 20 minutes. When the stabilizer mixture cools to 30°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 20 rpm for 15 minutes. Then, homogenize at 95°C and 40 bar to obtain the milk base material.

[0101] (3) Ultra-high temperature sterilization browning

[0102] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 152°C for 12 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0103] Example 6

[0104] like Figure 1 The flowchart shown illustrates the preparation method of the brown lactic acid bacteria beverage described in this embodiment, which includes the following steps:

[0105] (1) Preparation of fermented milk

[0106] Accurately weigh defatted powder at a ratio of 13 wt%, and weigh lactose hydrolase at a ratio of 0.3 wt%. Preheat the water for mixing to 55°C and set aside. Add the defatted powder and lactose hydrolase to the water for mixing (add water to make up to 100 wt%), and stir at 50 rpm for 15 minutes to ensure the raw materials dissolve. Let the resulting fermentation base stand at 55°C for 40 minutes to hydrate, and then pasteurize at 87°C for 300 seconds.

[0107] After sterilization, the fermentation substrate is cooled to 44°C, and fermentation inoculants (Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei in a mass ratio of 1:2:2) are added at a rate of 0.8 U / kg of fermentation substrate. The fermentation temperature is controlled at 44°C. The environment must be kept sterile during the addition of the inoculants. During fermentation, after 10 hours, samples are taken to observe and measure the acidity and pH of the product. If the product has formed a good gel structure, with a smooth, flat mirror-like surface, and a pH between 3.6 and 4.0, and an acidity between 140 and 160, fermentation can be stopped; otherwise, fermentation should continue.

[0108] After the above fermentation is completed, the resulting fermented milk is subjected to demulsification treatment. The demulsification stirring speed is 50 rpm and the demulsification time is 15 min. The demulsified yogurt is temporarily stored in a sterile container at a storage temperature of ≤7℃±1℃.

[0109] (2) Secondary batching

[0110] In this embodiment, the total amount of raw materials for preparing the brown lactic acid bacteria includes the following components in terms of mass content: 20wt% fermented milk, 0.2wt% soybean polysaccharide, 0.2wt% pectin, 5wt% arabinose, 0.012wt% sucralose, 0.1wt% citric acid, and water to make up to 100%.

[0111] Accurately weigh the selected amounts of soybean polysaccharide and pectin, and add them to 70°C hot water at 30 times their weight of the raw materials. Stir at 30 rpm for 20 minutes. When the stabilizer mixture solution cools to 40°C, add the selected amounts of fermented milk, arabinose, and sucralose to the mixture solution, and add water to make up to 100% (excluding the water used for the citric acid solution in the subsequent acid addition step). Stir at 30 rpm for 15 minutes. Then, homogenize at 98°C and 200 bar to obtain the milk base material.

[0112] (3) Ultra-high temperature sterilization browning

[0113] The emulsion base material is subjected to ultra-high temperature sterilization and browning treatment at 152°C for 12 seconds, until the solution reaches approximately 750°C (Pantone color chart). Subsequently, it is acidified using an aseptic pre-acidification system, by adding a selected amount of citric acid solution online to adjust the acidity of the system, maintaining the final product acidity between 38-42°T. Aseptic cold filling technology is used, i.e., aseptic filling is carried out at 20-25°C, with a nitrogen concentration of 99.99%, a nitrogen pressure of 1.5±0.2 bar, and a nitrogen flow rate of 1.5±0.2 slm.

[0114] Example 7

[0115] The preparation method of the brown lactic acid bacteria beverage described in this embodiment is the same as that in Embodiment 1, except that arabinose is not added, but 2 wt% erythritol is added according to the sweetness. The sweetness of the lactic acid bacteria at this addition ratio is similar to that of adding 4 wt% arabinose.

[0116] Example 8

[0117] The preparation method of the brown lactic acid bacteria beverage described in this embodiment is the same as that in Embodiment 1, except that the lactose hydrolase is not added for lactose hydrolysis.

[0118] Example 9

[0119] The preparation method of the brown lactic acid bacteria beverage described in this embodiment is the same as that in Embodiment 1, except that the soybean polysaccharide and pectin stabilizing system is replaced with a 0.3wt% CMC FM9 and 0.2wt% PGA stabilizing system.

[0120] Comparative Example 1

[0121] The preparation method of the brown lactic acid bacteria beverage described in this comparative example follows the traditional lactic acid bacteria beverage processing method, that is, the traditional method of browning before fermentation, and specifically includes the following steps:

[0122] (1) Preparation of fermented milk

[0123] After dissolving skim milk powder in water at a ratio of 12 wt%, add 1.5 wt% glucose and keep the dissolved skim milk powder at 50°C for 35 minutes to hydrate. Then, heat the liquid to 96°C and keep it at 3 hours for browning. After obtaining the browned liquid, cool it down to 43°C and add Lactobacillus paracasei (0.5 U / kg) for fermentation to obtain fermented milk that meets the requirements.

[0124] (2) Secondary batching

[0125] Using a combination of soybean polysaccharide and pectin for stability, 0.5% soybean polysaccharide and 0.2% pectin were dissolved in 30 times their volume of hot water at 60-70℃, followed by the addition of 7% white sugar and the addition of fermented milk to a final volume of 1000 kg. After thorough mixing, flavoring was added, followed by sterilization and bottling.

[0126] Comparative Example 2

[0127] The preparation method of the brown lactic acid bacteria beverage described in this comparative example is the same as that in Example 2, except that in step (3), after the secondary ingredient preparation, an online acid adjustment step is performed before the ultra-high pressure sterilization browning treatment.

[0128] Comparative Example 3

[0129] The preparation method of the brown lactic acid bacteria beverage described in this comparative example is the same as that in Example 2, the only difference is that in step (3), after the secondary ingredient preparation, the ultra-high pressure sterilization temperature is 122℃ and 4s, which is a common process.

[0130] Experimental Example

[0131] 1. Product property testing

[0132] The properties of the lactic acid bacteria beverages prepared in Examples 1-9 and Comparative Examples 1-3 were tested, and the evaluation indicators included:

[0133] Centrifugal sedimentation rate: Centrifugal sedimentation rate is an important indicator for evaluating the stability of milk beverages. The test steps are as follows: Take 30-40g of sample into a 50mL centrifuge tube, centrifuge at 4000r / min for 20min, pour off the supernatant, invert the centrifuge tube on filter paper and let it stand for 1min, wipe the tube mouth dry and weigh it. The results are presented in the form of mean and variance.

[0134] Particle size analyzer: BECKMAN LA960 laser particle size analyzer, which uses Mie scattering and Fraunhofer laser diffraction theory to detect the particle size of suspensions.

[0135] The test results are shown in Table 1 below.

[0136] Table 1 Product Property Test Results

[0137] Serial Number Particle size μm Centrifugal sedimentation rate % Final product color (Pantone color chart) Example 1 1.67 0.18 A lighter orange-brown, lighter than 7507C, not the color I expected. Example 2 1.51 0.18 Reaching 7507C, achieving the desired color. Example 3 1.77 0.27 A lighter orange-brown, lighter than 7507C, not the color I expected. Example 4 1.62 0.23 A lighter orange-brown, lighter than 7507C, not the color I expected. Example 5 2.19 0.28 Reaching 7507C, achieving the desired color. Example 6 2.51 0.25 Reaching 7507C, achieving the desired color. Example 7 1.97 0.26 A deeper creamy yellow, lighter than 7507C, not the color I expected. Example 8 2.13 0.26 A lighter orange-brown, lighter than 7507C, not the color I expected. Example 9 3.09 0.36 Reaching 7507C, achieving the desired color. Comparative Example 1 2.81 0.37 Reaching 7507C, achieving the desired color. Comparative Example 2 2.11 0.27 A deeper creamy yellow, lighter than 7507C, not the color I expected. Comparative Example 3 1.58 0.20 It is basically milky white, which is not the expected color.

[0138] It is evident that the Maillard reaction occurs under suitable sugar content, temperature, and reaction time. In Example 1, the low arabinose content, and in Examples 3 and 4, the short reaction time or low reaction temperature, all negatively impacted the Maillard reaction, resulting in the final product color not meeting the expected color. In Examples 5 and 6, the ratio of soybean polysaccharide and pectin in the stabilization system affected the particle size and stability of the product. In Example 7, the added erythritol could not undergo a Maillard reaction with the protein, affecting the final product color. In Example 8, the absence of lactase prolonged the fermentation time, increasing protein aggregation and affecting the product particle size. Furthermore, the lack of lactase reduced the amount of reacting sugars in the system, resulting in the color not meeting the expected color. In Example 9, the stabilization system using CMC and gellan gum resulted in a larger final product particle size and higher centrifugal sedimentation rate.

[0139] In Comparative Example 1, since only Lactobacillus paracasei was used for fermentation, the fermented dairy products had a unique aroma. However, Lactobacillus paracasei alone was in the reproduction stage for the first 24 hours of fermentation, with a slow rate of protein decomposition and passage. It needed to enter the rapid acid and aroma production stage after 24 hours. However, the overall fermentation time was long, and the protein particle aggregation was obvious, with a high particle size and sedimentation rate. Comparative Example 2 used a pre-acidification process, which increased the production time. In Comparative Example 3, since a common sterilization process of 122℃ and 4s was used, almost no obvious browning occurred, and the expected product color was not achieved.

[0140] 2. Capacity expansion rate

[0141] Using the traditional pre-browning and pre-acidification process of Lactobacillus paracasei (i.e., the scheme in Comparative Example 1) as a control, the relative production capacity (h) of each example and comparative example scheme was calculated based on the output of a normal 40T production line.

[0142] Each embodiment and comparative example includes the steps of weighing, preparing materials, hydration, pasteurization (or traditional browning), adding microbial strains, fermentation, demulsification, mixing, adding acid, homogenization, ultra-high temperature sterilization (browning), and aseptic filling. Among them, the weighing step is calculated as 1 hour, the preparing materials step as 1 hour, the hydration step as 0.5 hours, the adding microbial strain step as 0.5 hours, the demulsification step as 0.5 hours, the mixing step as 1 hour, the homogenization step as 1 hour, and the aseptic filling step as 1 hour. The remaining pasteurization (or traditional browning), fermentation, adding acid, and ultra-high temperature sterilization (browning) steps are different for each individual.

[0143] The calculation process according to the technical routes of each embodiment and comparative example is shown in Table 2 below.

[0144] Table 2 Calculation of Capacity Increase Rate

[0145]

[0146]

[0147] It is evident that the preparation method of the brown lactic acid beverage described in this invention, which employs ultra-high pressure sterilization and browning after fermentation, effectively improves the efficiency of the entire process and increases production capacity.

[0148] 3. Taste and flavor evaluation experiments were conducted on lactic acid bacteria beverages.

[0149] The taste and flavor of the lactic acid bacteria beverages prepared in Examples 1-9 and Comparative Examples 1-3 were evaluated using the following methods:

[0150] Number of participants: 300;

[0151] Testing method: Tasting dimensions include product preference, sweetness, sourness, smoothness, and flavor. An anonymous scoring method is used, with a maximum score of 10 points for each indicator. The higher the score for each indicator, the better the effect. The tasting results are statistically analyzed.

[0152] Flavor profile: The Maillard flavor is analyzed from multiple dimensions. A professional panel evaluation team evaluates and scores the strength of each dimension of flavor and draws a multi-dimensional flavor profile, which can illustrate the dimensional changes of Maillard flavor and overall flavor in different schemes of this patent.

[0153] The test results are shown in Tables 3 and 4 below.

[0154] Table 3 Sample Test Results

[0155]

[0156]

[0157] Table 4. Overall Product Taste Preference Test Data (300 participants)

[0158]

[0159] It is evident that the Maillard reaction not only affects product color but also significantly impacts flavor. In Example 1, the low arabinose content, and in Examples 3 and 4, the short reaction time or low temperature all negatively affected the Maillard reaction, resulting in a weak Maillard flavor in the final product and impacting the overall flavor. In Examples 5 and 6, the ratio of soybean polysaccharides and pectin in the stabilization system affected the particle size, producing a slightly astringent and burnt taste. In Example 7, the added erythritol could not react with the protein in the Maillard reaction; only galactose, broken down by lactase, reacted, resulting in a very weak Maillard flavor. In Example 8, the lack of lactase and prolonged fermentation time increased protein aggregation, affecting the particle size. The absence of lactase also reduced the amount of reacting sugars in the system, ultimately resulting in a weak Maillard flavor and an astringent taste. In Example 9, the use of CMC and gellan gum in the stabilization system resulted in a high viscosity of the final product, leading to tube sticking during ultra-high temperature sterilization, a burnt flavor, and a viscous texture.

[0160] Comparative Example 1 uses a traditional brown lactic acid bacteria fermentation method, which results in a long fermentation time, significant protein particle aggregation, and a bitter taste. In contrast, Comparative Example 2, because the Maillard reaction requires a neutral or slightly acidic environment, adding acid beforehand lowers the overall pH of the system, affecting the Maillard reaction rate. Comparative Example 3, using a common sterilization process at 122℃ for 4 seconds, showed almost no significant browning, thus affecting the product's flavor.

[0161] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a brown lactic acid bacteria beverage, characterized in that, Includes the following steps: (1) Take defatted powder and add water to make ingredients, sterilize to obtain fermentation base material, add fermentation agent to the fermentation base material, and ferment and demulsify to obtain fermented milk for later use; (2) Add stabilizers and reducing sugars to the fermented milk and mix and homogenize to obtain milk base material; (3) The milk base material is subjected to ultra-high temperature sterilization and browning treatment, and the resulting brown milk is adjusted and filled to obtain the product; Step (1) also includes the step of adding lactose hydrolase to the fermentation base material; In Step (2): the stabilizer includes soybean polysaccharide and pectin; the reducing sugar includes arabinose and sucralose; In Step (3), the temperature of the ultra-high temperature sterilization and browning treatment step is 147-157℃ and the time is 9-15 seconds.

2. The method for preparing the brown lactic acid bacteria beverage according to claim 1, characterized in that, The total amount of the fermentation base includes: 10-13 wt% defatted powder, 0.1-0.3 wt% lactose hydrolase, and water to make up to 100%.

3. The method for preparing the brown lactic acid bacteria beverage according to claim 1, characterized in that, In step (1), the fermentation agent includes a mixed agent of Lactobacillus helveticus, Streptococcus thermophilus, and Lactobacillus paracasei.

4. The method for preparing the brown lactic acid bacteria beverage according to claim 3, characterized in that, The dosage of the fermentation agent is based on the dosage of the fermentation substrate, which is 0.3-0.8 U / kg.

5. The method for preparing the brown lactic acid bacteria beverage according to any one of claims 1-4, characterized in that, In step (1): The fermentation step is carried out at a temperature of 43±1℃, and the final control of the fermentation step is a pH value of 3.6-4.0 and an acidity of 140-160; and / or, The sterilization step is performed at a temperature of 85±2℃ for a sterilization time of 300±20s; and / or, The stirring speed in the demulsification step is 30-50 r / min, and the demulsification time is 15 min; and / or, The ingredient preparation step further includes a step of preheating water to 45-55°C before preparation; and / or, The ingredient preparation step is followed by a hydration treatment step.

6. The method for preparing the brown lactic acid bacteria beverage according to claim 5, characterized in that, The hydration treatment step includes a step of standing hydration at 45-55°C for 30-40 minutes.

7. The method for preparing the brown lactic acid bacteria beverage according to any one of claims 1-4, characterized in that, In step (2), the homogenization temperature is 95-98°C, and the homogenization pressure is 40-200 bar; and / or, In step (2), the temperature of the mixing step is 30-40℃; and / or, Step (2) further includes the step of adding water to the stabilizer to dissolve it.

8. The method for preparing the brown lactic acid bacteria beverage according to claim 7, characterized in that, The temperature of the chemical material is 60-70℃.

9. The method for preparing the brown lactic acid bacteria beverage according to any one of claims 1-4, characterized in that, In step (3), the acid adjustment step includes a sterile online acid adjustment step.

10. The method for preparing the brown lactic acid bacteria beverage according to claim 9, characterized in that, The acidifier used in the acidification step includes citric acid.

11. The method for preparing the brown lactic acid bacteria beverage according to any one of claims 1-4, characterized in that, The brown lactic acid bacteria, based on the total amount of raw materials used in its preparation, comprises the following components in terms of mass content: 18-20 wt% fermented milk, 0.3-0.6 wt% stabilizer, 4.008-6.012 wt% reducing sugar, 0.1-0.2 wt% citric acid, and water to make up to 100%.

12. The method for preparing the brown lactic acid bacteria beverage according to claim 11, characterized in that, The brown lactic acid bacteria, based on the total amount of raw materials used in its preparation, comprises the following components by mass: 18-20 wt% fermented milk, 0.2-0.4 wt% soybean polysaccharide, 0.1-0.2 wt% pectin, 4-6 wt% arabinose, 0.008-0.012 wt% sucralose, 0.1-0.2 wt% citric acid, with water added to make up to 100%.

13. A brown lactic acid bacteria beverage prepared by the method according to any one of claims 1-12.

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