Fermented camel yogurt beverage and preparation method thereof

Abstract

The invention discloses a fermented camel yogurt beverage and a preparation method thereof, and relates to the technical field of fermented dairy products. According to the invention, lactulose is cooperated with a fermentation strain to realize in-vivo and in-vitro dual probiotic synergy, Kluyveromyces marxianus is cooperated with fruit juice to generate natural fragrance, a flavor-guided fermentation technology and a two-stage temperature-controlled fermentation technology are applied, and an ultra-high pressure homogenization technology is combined, so that the flavor-guided fruit juice is obtained. Finally, the fermented camel yogurt beverage which is fine and stable in texture, natural and coordinated in flavor, outstanding in probiotic function, long in shelf life and excellent in weather resistance is obtained.

Description

Technical Field

[0001] This invention relates to the field of fermented dairy product technology, specifically to a fermented camel yogurt beverage and its preparation method. Background Technology

[0002] With increasing health awareness and the diversification of the dairy market, specialty dairy products with unique nutritional value are gaining popularity among consumers. Camel milk, as a natural and healthy milk source, is rich in protein, vitamins, and minerals, and has low allergenicity, making it an ideal raw material for developing high-end fermented dairy products. However, the inherent characteristics of camel milk present significant challenges to its processing. Furthermore, the monotonous flavor and severe post-acidification issues of traditional fermented dairy products also hinder their market promotion. Therefore, developing a fermented camel yogurt beverage that effectively solves the problem of camel milk protein stability while endowing the product with a rich and harmonious flavor and good functional properties has become an urgent technical problem to be solved in this field. Summary of the Invention

[0003] The purpose of this invention is to provide a fermented camel yogurt beverage and its preparation method, so as to solve the problems mentioned in the background art.

[0004] In a first aspect, the present invention provides a fermented camel yogurt beverage, comprising the following ingredients by weight:

[0005] 615-635 portions of sterile water;

[0006] 280-300 servings of raw camel milk;

[0007] 60-80 parts xylitol;

[0008] 5-6 parts of compound stabilizer;

[0009] Sodium citrate 1-1.3 parts;

[0010] Citric acid 0.8-1 part;

[0011] Malic acid 0.5-0.8 parts;

[0012] Lactic acid 2.5-2.8 parts;

[0013] 8-10 servings of juice;

[0014] 0.02-0.03 parts of fermentation starter;

[0015] 10-15 parts of lactulose;

[0016] 0.005-0.01 parts of Kluyveromycin.

[0017] It should be noted that this invention introduces lactulose. Lactulose is a high-quality prebiotic obtained by the isomerization of lactose. It is not digested in the human intestine but can specifically promote the proliferation of beneficial bacteria such as Bifidobacteria and Lactobacillus. In this fermentation system, the addition of lactulose can produce a synergistic effect with the fermentation strains. On the one hand, it provides a preferential carbon source for the fermentation strains, especially Lactobacillus and Lactococcus, which can promote bacterial growth and reproduction, accelerate acid production, shorten the fermentation cycle, and optimize the bacterial community ratio. On the other hand, the lactulose remaining after fermentation enters the human body with the fermented camel yogurt beverage and can continue to exert its prebiotic effects. It works synergistically with the ingested live bacteria to regulate the balance of intestinal flora, achieving a dual proliferation effect in vivo and in vitro, thus giving the fermented camel yogurt beverage continuous intestinal health benefits. In addition, lactulose has a mild sweetness, about 50% of that of sucrose. When combined with xylitol, it can further optimize the sweetness curve of the fermented camel yogurt beverage and reduce unpleasant sweetness.

[0018] As a preferred embodiment of the present invention, the compound stabilizer is two or more of sodium carboxymethyl cellulose, sodium tripolyphosphate, pectin, polyglycerol fatty acid ester, xanthan gum, and gum arabic.

[0019] It should be noted that this invention introduces a compound stabilizer (two or more of sodium carboxymethyl cellulose, sodium tripolyphosphate, pectin, polyglycerol fatty acid esters, xanthan gum, and gum arabic). Pectin / xanthan gum / gum arabic, as a natural polysaccharide, is not only an excellent thickening and stabilizing agent that synergizes with existing protein systems to further enhance the stability and thick texture of fermented camel yogurt drinks, but also acts as a prebiotic. It is not digested in the intestines and selectively promotes the proliferation of beneficial bacteria such as Bifidobacteria commonly found in the gut of healthy individuals. Synergistically, it contributes significant intestinal health benefits to fermented camel yogurt drinks, achieving a dual function of stability and probiotics. Sodium carboxymethyl cellulose primarily provides stability through thickening; sodium tripolyphosphate maintains system stability by chelating metal ions and dispersing proteins; and polyglycerol fatty acid esters act as emulsifiers to prevent fat precipitation. These three components mainly contribute to the physicochemical stability of fermented camel yogurt drinks.

[0020] As a preferred embodiment of the present invention, the juice is one or more of apple juice, mango juice and pineapple juice.

[0021] It should be noted that this invention introduces flavor-guided fermentation technology. By adding Kluyveromyces martensii and synergizing with the fruit juice, the natural generation and enhancement of flavor are achieved. This specific yeast strain can efficiently metabolize specific flavor precursors in fruit juice. For example, it converts amino acids and fatty acids in apple juice into rich natural ester aroma compounds, such as ethyl acetate and ethyl hexanoate. In mango juice, the yeast can metabolize branched-chain amino acids (such as leucine and isoleucine) to produce compounds such as isoamyl acetate, which imparts a tropical fruit aroma. In pineapple juice, it metabolizes short-chain fatty acids such as butyric acid to produce substances such as ethyl butyrate, which give the fermented camel yogurt beverage a fresh fruity aroma. The resulting flavor is endogenous, originating from the fermentation and metabolic process, rather than a simple exogenous addition. It is generated in situ through biological metabolic pathways and is seamlessly integrated with the fruit juice base. This makes the flavor of the fermented camel yogurt beverage more natural, harmonious, and long-lasting, improving the flavor stability of the fermented camel yogurt beverage and increasing consistency between different batches.

[0022] As a preferred embodiment of the present invention, the fermentation strain is any of several of the following: Streptococcus salivarius subsp. thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus fattya, Lactococcus lactis subsp. fattya, and Lactobacillus helveticus.

[0023] As a preferred embodiment of the present invention, the fermentation strain needs to undergo activation pretreatment, and the specific steps are as follows:

[0024] Add the fermentation starter to sterile water at 35°C, add cysteine ​​hydrochloride, and let it stand for 15-25 minutes to activate.

[0025] As a preferred embodiment of the present invention, the ratio of the fermentation strain, sterile water and cysteine ​​hydrochloride is 1g:(200-300)mL:(0.1-0.15)g.

[0026] A second aspect of the present invention provides a method for preparing a fermented camel yogurt beverage, comprising the following steps:

[0027] S1. Add xylitol, lactulose and compound stabilizer to sterile water, stir at 85-90℃ for 15-20 min, cool to 10-15℃ to obtain the ingredient solution;

[0028] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5-8 minutes. Spray mixed acid solution during the stirring process. Add fruit juice and water to make up to the specified volume. Heat to 65-70℃ and homogenize under ultra-high pressure at 150-200MPa. Heat to 90±5℃ and sterilize for 300 seconds. Cool to 30±2℃ and fill the material to obtain the mixed emulsion.

[0029] It should be noted that this invention optimizes the homogenization process by employing ultra-high pressure homogenization technology. Under ultra-high pressure of 150-200 MPa, the fat globules and protein particles in camel milk are sheared and broken down into smaller, more uniform particles with a significantly narrower particle size distribution. This results in an extremely stable and delicate emulsion system, achieving a silky smooth texture and further enhancing the system's physical stability. Simultaneously, the ultra-high pressure homogenization process causes mechanical damage to the cell walls of microorganisms, exhibiting a certain non-thermal sterilization effect. This helps reduce the load on subsequent sterilization processes, providing a technological basis for better preservation of heat-sensitive components.

[0030] S3. Add fermentation starter and ferment the mixed emulsion at 30±2℃ for 18-22 hours until the acidity reaches 60-65°T; then add activated Max Kluyveromyces and continue fermentation at 25±2℃ for 4-6 hours until the acidity reaches or exceeds 70°T to obtain crude beverage.

[0031] It should be noted that this invention employs a two-stage temperature-controlled fermentation process. The first stage of fermentation primarily utilizes lactic acid bacteria, with the main purpose of rapidly producing acid to establish the basic acidity and texture of the fermented camel yogurt beverage. The second stage of fermentation activates the metabolic activity of Kluyveromyces martensii at a relatively low temperature. At this stage, the activity of lactic acid bacteria is slowed down, avoiding carbon source competition and creating optimal conditions for the yeast to fully utilize the flavor precursors in the fruit juice, enabling it to efficiently produce abundant natural ester aroma compounds. This staged fermentation strategy not only ensures the smooth completion of the fermentation process and the achievement of the acidity target but also enables the targeted generation and enhancement of flavor, resulting in a fermented camel yogurt beverage exhibiting a rich, naturally harmonious, and typical fermented flavor and fruity aroma.

[0032] S4. Allow the crude beverage to mature at room temperature for 1-4 hours, and monitor the carbon dioxide content in the container. During the maturation process, the carbon dioxide content in the container must be monitored. If the carbon dioxide content reaches the target range of 0.18-0.25 MPa, it is considered qualified. If it is not qualified, continue maturation until it is qualified.

[0033] As a preferred embodiment of the present invention, the specific preparation steps of the mixed acid solution are as follows:

[0034] Mix the weighed sodium citrate, citric acid, malic acid, lactic acid and 20 parts of sterile water according to the formula, stir at 55℃ until completely dissolved, and keep warm for later use.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] This invention achieves a synergistic effect between prebiotics and probiotics through the addition of lactulose, enhancing the intestinal health function of fermented camel yogurt beverages. Employing flavor-guided fermentation technology and a two-stage temperature-controlled fermentation process, it utilizes the biotransformation of Kluyveromyces martensii to generate natural ester flavor compounds, resulting in a fermented camel yogurt beverage exhibiting a rich, naturally harmonious, and typical fermented flavor and fruity aroma. Simultaneously, the application of ultra-high pressure homogenization technology further improves the texture and mouthfeel of the fermented camel yogurt beverage prepared by this invention and reduces the intensity of heat processing. In summary, the fermented camel yogurt beverage prepared by this invention has the advantages of excellent stability, delicate taste, rich flavor, strong functionality, and consistent quality. Detailed Implementation

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] The sources of some components in the preparation examples, embodiments, and comparative examples are as follows:

[0039] Table 1

[0040] Material source Xylitol Wuhan Jiyesheng Chemical Co., Ltd. Item No. W01297 Lactulose Sichuan Weikeqi Biotechnology Co., Ltd. Product No. wkq-03004 Streptococcus salivarius thermophilus subsp. Beijing BioBio Biotechnology Co., Ltd. Platform ID: bio-72768 Lactobacillus delbrueckii subsp. bulgaricus Beijing BioBio Biotechnology Co., Ltd. Platform ID: bio-67112 Lactococcus lactis subsp. milk fat Beijing BioBio Biotechnology Co., Ltd. Platform ID: bio-03523 Max Kluyveromycin Beijing BioBio Biotechnology Co., Ltd. Platform ID: bio-119798

[0041] Preparation Example 1

[0042] The fermentation starter culture needs to be activated and pretreated. The specific steps are as follows:

[0043] Take 0.3g of Streptococcus salivarius thermophilus subsp., 0.3g of Lactobacillus delbrueckii subsp. bulgaricus and 0.4g of Lactococcus lactis subsp. milk fat at 35℃ and add them to 250mL of sterile water. Add 0.1g of cysteine ​​hydrochloride, let stand for 20min to activate, centrifuge and dry.

[0044] Preparation Example 2

[0045] Kluyveromycin requires activation pretreatment, the specific steps of which are as follows:

[0046] Take 0.5g of Kluyveromyces martensii at 28℃ and add it to 200mL of sterile water. Add 0.1g of glucose, let it stand for 25min to activate, centrifuge, and dry.

[0047] Preparation Example 3

[0048] The specific steps for preparing the mixed acid solution are as follows:

[0049] Mix 1 part sodium citrate, 0.8 parts citric acid, 0.6 parts malic acid, 2.6 parts lactic acid and 20 parts sterile water, stir at 55°C until completely dissolved, and keep warm for later use.

[0050] Example 1

[0051] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0052] 605 portions of sterile water;

[0053] 290 servings of raw camel milk;

[0054] 70 parts xylitol;

[0055] 1.5 parts sodium carboxymethyl cellulose;

[0056] 4 parts pectin;

[0057] 25 parts of mixed acid solution;

[0058] Nine servings of apple juice;

[0059] 0.025 portions of fermentation starter;

[0060] Lactulose 12.5 parts;

[0061] 0.008 parts of Kluyveromycin.

[0062] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0063] S1. Add xylitol, lactulose, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution.

[0064] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add apple juice, add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0065] S3. Add the fermentation starter and ferment the mixed emulsion at 30°C for 20 hours until the acidity reaches 60°T. Then add the activated Max Kluyveromycin and continue fermenting at 25°C for 6 hours until the acidity exceeds 70°T to obtain the crude beverage.

[0066] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0067] The raw materials used in this embodiment are all substances obtained from Preparation Examples 1-3, and the same applies to other embodiments and comparative examples.

[0068] Example 2

[0069] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0070] 595 portions of sterile water;

[0071] 280 servings of raw camel milk;

[0072] 60 parts xylitol;

[0073] 1 part sodium carboxymethyl cellulose;

[0074] 3 parts pectin;

[0075] 25 parts of mixed acid solution;

[0076] 8 servings of apple juice;

[0077] 0.02 portions of fermentation starter;

[0078] 10 parts lactulose;

[0079] 0.005 parts of Max Kluyveromycin.

[0080] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0081] S1. Add xylitol, lactulose, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution.

[0082] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add apple juice, add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0083] S3. Add the fermentation starter and ferment the mixed emulsion at 30°C for 20 hours until the acidity reaches 60°T. Then add the activated Max Kluyveromycin and continue fermenting at 25°C for 6 hours until the acidity exceeds 70°T to obtain the crude beverage.

[0084] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0085] Example 3

[0086] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0087] 615 portions of sterile water;

[0088] 300 servings of raw camel milk;

[0089] 80 parts xylitol;

[0090] 2 parts sodium carboxymethyl cellulose;

[0091] 5 parts pectin;

[0092] 25 parts of mixed acid solution;

[0093] 10 servings of apple juice;

[0094] 0.03 portions of fermentation starter;

[0095] 15 parts lactulose;

[0096] 0.01 parts of Kluyveromycin.

[0097] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0098] S1. Add xylitol, lactulose, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution.

[0099] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add apple juice, add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0100] S3. Add the fermentation starter and ferment the mixed emulsion at 30°C for 20 hours until the acidity reaches 60°T. Then add the activated Max Kluyveromycin and continue fermenting at 25°C for 6 hours until the acidity exceeds 70°T to obtain the crude beverage.

[0101] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0102] Comparative Example 1

[0103] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0104] 605 portions of sterile water;

[0105] 290 servings of raw camel milk;

[0106] 70 parts xylitol;

[0107] 1.5 parts sodium carboxymethyl cellulose;

[0108] 4 parts pectin;

[0109] 22.5 parts of mixed acid solution;

[0110] Nine servings of apple juice;

[0111] 0.025 portions of fermentation starter;

[0112] 0.008 parts of Kluyveromycin.

[0113] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0114] S1. Add xylitol, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution;

[0115] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add apple juice, add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0116] S3. Add the fermentation starter and ferment the mixed emulsion at 30°C for 20 hours until the acidity reaches 60°T. Then add the activated Max Kluyveromycin and continue fermenting at 25°C for 6 hours until the acidity exceeds 70°T to obtain the crude beverage.

[0117] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0118] The difference between this comparative example and Example 1 is that no lactulose was added.

[0119] Comparative Example 2

[0120] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0121] 605 portions of sterile water;

[0122] 290 servings of raw camel milk;

[0123] 70 parts xylitol;

[0124] 1.5 parts sodium carboxymethyl cellulose;

[0125] 4 parts pectin;

[0126] 22.5 parts of mixed acid solution;

[0127] 0.025 portions of fermentation starter;

[0128] Lactulose 12.5 parts;

[0129] 0.008 parts of Kluyveromycin.

[0130] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0131] S1. Add xylitol, lactulose, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution.

[0132] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0133] S3. Add the fermentation starter and ferment the mixed emulsion at 30°C for 20 hours until the acidity reaches 60°T. Then add the activated Max Kluyveromycin and continue fermenting at 25°C for 6 hours until the acidity exceeds 70°T to obtain the crude beverage.

[0134] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0135] The difference between this comparative example and Example 1 is that apple juice was not added.

[0136] Comparative Example 3

[0137] A fermented camel yogurt beverage comprises the following ingredients by weight:

[0138] 605 portions of sterile water;

[0139] 290 servings of raw camel milk;

[0140] 70 parts xylitol;

[0141] 1.5 parts sodium carboxymethyl cellulose;

[0142] 4 parts pectin;

[0143] 22.5 parts of mixed acid solution;

[0144] Nine servings of apple juice;

[0145] 0.025 portions of fermentation starter;

[0146] 12.5 parts lactulose.

[0147] A method for preparing a fermented camel yogurt beverage includes the following steps:

[0148] S1. Add xylitol, lactulose, sodium carboxymethyl cellulose and pectin to sterile water, stir at 90°C for 15 min, and cool to 10°C to obtain the ingredient solution.

[0149] S2. Add raw camel milk to the ingredient solution obtained in S1 and stir for 5 minutes. Spray mixed acid solution during the stirring process. Add apple juice, add water to make up to the specified volume, heat to 65°C, homogenize under ultra-high pressure at 150MPa, heat to 90°C, sterilize for 300 seconds, cool to 30°C, and fill the material to obtain mixed emulsion.

[0150] S3. Add fermentation starter, place the mixed emulsion at 30°C for 26 hours to ferment until the acidity exceeds 70°T, and obtain crude beverage.

[0151] S4. After the crude beverage is aged at room temperature for 3 hours, the aged crude beverage is sterilized again at 80℃ for 10 minutes, cooled to room temperature, and packaged to obtain fermented camel yogurt beverage.

[0152] The difference between this comparative example and Example 1 is that Max Kluyveromycin was not added, and S3 did not use staged temperature-controlled fermentation.

[0153] test:

[0154] I. System Stability Testing

[0155] Take 50 mL of sample into a 100 mL centrifuge tube and store it at 4 °C for 21 days. Centrifuge at 4000 r / min for 15 min, collect the precipitate, and weigh the precipitate.

[0156] Precipitation rate (%) = (mass of precipitate / mass of sample) × 100%.

[0157] The test results are shown in Table 1.

[0158] Table 1

[0159] sample Extraction rate (%) Example 1 1.9 Example 2 1.5 Example 3 2.2 Comparative Example 1 4.5 Comparative Example 2 2.5 Comparative Example 3 4.8

[0160] Results analysis: The precipitation rates of samples in Examples 1-3 were all below 2.5%, while the precipitation rates of Comparative Examples 1 and 3 were both above 4.5%, indicating that the addition of lactulose and the two-stage temperature-controlled fermentation process have a synergistic effect on maintaining the stability of the system.

[0161] II. Viable Bacterial Count Determination

[0162] Referring to GB 4789.35-2016 National Food Safety Standard, Microbiological Examination of Food - Lactic Acid Bacteria Examination, the number of viable lactic acid bacteria in the samples was determined immediately after fermentation (day 0) and after 21 days of storage using the pour culture method.

[0163] The test results are shown in Table 2.

[0164] Table 2

[0165] sample viable bacteria count at day 0 (CFU / mL) 21-day viable cell count (CFU / mL) Example 1 <![CDATA[3.2×10 8 ]]> <![CDATA[5.6×10 7 ]]> Example 2 <![CDATA[2.9×10 8 ]]> <![CDATA[4.8×10 7 ]]> Example 3 <![CDATA[3.5×10 8 ]]> <![CDATA[6.2×10 7 ]]> Comparative Example 1 <![CDATA[3.0×10 8 ]]> <![CDATA[8.1×10 5 ]]> Comparative Example 2 <![CDATA[2.8×10 8 ]]> <![CDATA[3.4×10 6 ]]> Comparative Example 3 <![CDATA[2.6×10 8 ]]> <![CDATA[3.4×10 6 ]]>

[0166] Results analysis: At the end of fermentation, the viable count of lactic acid bacteria in each group of samples reached 1×10⁻⁶. 8 CFU / mL or higher. After 21 days of storage, the viable count of lactic acid bacteria in Examples 1-3 remained at 1×10⁻⁶. 6 The viable count was above CFU / mL, while in Comparative Example 1 it decreased to 1×10⁻⁶. 6 The concentration of CFU / mL is below 1. This indicates that lactulose, as a prebiotic, effectively promotes the proliferation of lactic acid bacteria and maintains a high cell survival rate during the shelf life.

[0167] III. Determination of Physicochemical Indicators

[0168] Acidity (°T): Determined according to GB 5009.239-2016 National Food Safety Standard - Determination of Acidity in Food. Post-acidification assessment: The acidity difference (Δacidity) between 0 days and 21 days of storage was measured.

[0169] The test results are shown in Table 3.

[0170] Table 3

[0171]

[0172]

[0173] Results analysis: The final acidity of all samples met the standard (≥70°T). The Δ acidity of Examples 1-3 was significantly lower than that of Comparative Examples 1-3, indicating that the formulation and process of the present invention effectively delayed the post-acidification process of the samples.

[0174] IV. Flavor Compound Analysis

[0175] The volatile flavor compound ethyl acetate in the finished product was quantitatively analyzed using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). (Detection limit: 0.5 mg / L)

[0176] The test results are shown in Table 4.

[0177] Table 4

[0178] sample Ethyl acetate content (mg / L) Example 1 15.5 Example 2 14.7 Example 3 16.1 Comparative Example 1 12.7 Comparative Example 2 ND Comparative Example 3 ND

[0179] Results Analysis: The content of ethyl acetate detected in the samples of Examples 1-3 was significantly higher than that in Comparative Examples 2 and 3. This indicates that the flavor-guided fermentation technology of fruit juice combined with staged fermentation of Kluyveromyces martensii, used in this invention, successfully achieved the targeted synthesis and enhancement of endogenous flavor substances.

[0180] V. Sensory Evaluation Results

[0181] A sensory evaluation team of 10 people was formed to conduct blind evaluations and score the product’s appearance (30 points), taste / texture (40 points), and flavor (30 points) on a 100-point scale.

[0182] Table 5

[0183] sample Appearance Taste / Texture Flavor Total Score Example 1 28.5±1.2 36.8±1.5 26.9±1.8 92.2±3.1 Example 2 27.8±1.4 35.9±1.7 25.8±1.6 89.5±3.2 Example 3 28.2±1.3 36.5±1.6 26.5±1.7 91.2±3.0 Comparative Example 1 25.1±1.8 33.2±2.1 24.0±2.0 82.3±4.5 Comparative Example 2 27.9±1.5 35.9±1.7 22.5±1.9 86.3±3.8 Comparative Example 3 26.3±1.7 34.1±2.0 23.1±2.2 83.5±4.6

[0184] Results analysis: The scores of the samples in Examples 1-3 were significantly higher than those in Comparative Examples 2 and 3. Among them, Example 1 achieved the highest scores in product stability (high appearance score), smoothness (high taste score), and flavor harmony and intensity (high flavor score), and had the best overall sensory quality.

[0185] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0186] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A fermented camel acid dairy drink, characterized by: The following raw materials are included by weight parts: Sterile water 615-635 parts; Raw camel milk 280-300 parts; Xylitol 60-80 parts; Compound stabilizer 5-6 parts; Sodium citrate 1-1.3 parts; Citric acid 0.8-1 part; Malic acid 0.5-0.8 parts; Lactic acid 2.5-2.8 parts; Fruit juice 8-10 parts; Fermentation strain 0.02-0.03 parts; Lactulose 10-15 parts; Kluyveromyces marxianus 0.005-0.01 parts.

2. The fermented camel milk drink according to claim 1, characterized in that: The compound stabilizer is two or more of sodium carboxymethyl cellulose, sodium tripolyphosphate, pectin, polyglycerol fatty acid ester, xanthan gum and gum arabic.

3. The fermented camel milk drink according to claim 1, characterized in that: The fruit juice is one or several of apple juice, mango juice and pineapple juice.

4. The fermented camel milk drink according to claim 1, characterized in that: The fermentation strain is any of Streptococcus salivarius subsp. thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis, Lactococcus lactis subsp. cremoris and Lactobacillus helveticus.

5. The fermented camel milk drink according to claim 1, characterized in that: The fermentation strain needs to be activated and pretreated, and the specific steps are as follows: Take the fermentation strain and add it to 35℃ sterile water, add cysteine hydrochloride, and stand for 15-25min for activation.

6. The fermented camel milk drink according to claim 5, characterized in that: The dosage ratio of the fermentation strain, sterile water and cysteine hydrochloride is 1g:(200-300)mL:(0.1-0.15)g.

7. The method of claim 1-6, wherein the method of preparing a fermented camel milk drink is characterized by: The following steps are included: S1, add xylitol, lactulose and compound stabilizer to sterile water, stir at 85-90℃ for 15-20min, cool to 10-15℃, and obtain a batching solution; S2, add raw camel milk to the batching solution obtained in S1, stir for 5-8min, spray mixed acid liquid during stirring; add fruit juice, add water to the specified volume, heat to 65-70℃, and perform ultrahigh pressure homogenization treatment at 150-200MPa, heat to 90±5℃, sterilize for 300s, cool to 30±2℃, fill the material, and obtain a mixed emulsion; S3, add fermentation strain, and start the first stage fermentation of the mixed emulsion at 30±2℃ for 18-22h; then add activated Kluyveromyces marxianus, and start the second stage fermentation at 25±2℃ for 4-6h, to obtain a crude product beverage; S4, post-ripen the crude product beverage at room temperature for 1-4h, sterilize the post-ripened crude product beverage again at 78-80℃, cool to room temperature, and package to obtain a fermented camel yogurt beverage.

8. The method for preparing a fermented camel yogurt beverage according to claim 7, characterized in that: In the step S2, the specific configuration steps of the mixed acid liquid are as follows: Mix the weighed sodium citrate, citric acid, malic acid, lactic acid and 20 parts of sterile water according to the ratio, stir at 55℃ until completely dissolved, and keep warm for standby.

9. The method for preparing a fermented camel yogurt beverage according to claim 7, characterized in that: In the step S3, the first stage acidity needs to reach 60-65°T, and the second stage acidity needs to reach or exceed 70°T.

10. The method for preparing a fermented camel yogurt beverage according to claim 7, characterized in that: In the step S4, the carbon dioxide gas content in the container needs to be monitored during the post-ripening stage. If the carbon dioxide gas content reaches the target range of 0.18-0.25MPa, it is qualified. If it is not qualified, continue to post-ripen until it is qualified.

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