Low-temperature yoghurt containing seaweed dietary fibers and preparation method of low-temperature yoghurt

Abstract

The invention relates to the technical field of dairy products, in particular to low-temperature yoghurt containing seaweed dietary fibers and a preparation method of the low-temperature yoghurt. The low-temperature yoghourt containing the seaweed dietary fibers is prepared from the following raw materials in parts by weight: 80-92 parts of dairy products; 5 to 10 parts of sugar; 0.16 to 0.3 part of seaweed dietary fiber; and 0.1 to 0.12 part of a fermentation strain. The invention has the beneficial effects that the sea extract TM (seaweed dietary fiber) is used as a raw material to replace agar, pectin, gelatin, modified starch, CMC, gellan gum and the like which are commonly used in the original yoghourt and belong to food additives to serve as a thickening and stabilizing agent of the yoghourt, so that the taste and the texture of the yoghourt are improved, the water holding rate and the viscosity of the yoghourt are effectively improved, and the flavor of the yoghourt is improved. The milk powder can prevent whey from being separated out, also can supplement dietary fibers, promote intestinal health and increase the nutritional value of the product, and also can meet the needs of consumers and customers for pursuing'clean label 'products at present.

Description

Technical Field

[0001] The invention relates to the technical field of dairy products, and in particular to a low-temperature yogurt containing seaweed dietary fiber and a preparation method thereof. Background Art

[0002] Yogurt is made from raw cow (sheep) milk or milk powder, which is fermented by inoculating Lactobacillus bulgaricus and Streptococcus thermophilus after mixing, homogenization, high-temperature sterilization and other processes. Yogurt can be divided into room temperature yogurt (also known as "sterilized yogurt") and low-temperature yogurt (also known as "live bacteria yogurt") based on whether it has undergone secondary sterilization. Low-temperature yogurt is popular among consumers because of its smooth taste, unique flavor and the presence of a variety of probiotics, which has the effects of promoting intestinal absorption, improving intestinal health and balancing intestinal flora. However, during storage or transportation, yogurt often has undesirable phenomena such as low viscosity, rough texture, poor taste, and whey precipitation. In traditional yogurt production and processing, one or more thickeners and stabilizers are often added to solve the above problems. Commonly used thickeners and stabilizers include agar, sodium alginate, sodium carboxymethyl cellulose, gelatin or modified starch, etc. These raw materials are all food additives and do not meet consumers' requirements for health and clean labels.

[0003] Chinese invention CN117751979A discloses a thickening stabilizer and a preparation method thereof, and a flavored yogurt and a preparation method thereof. The thickening stabilizer comprises stabilizer A and stabilizer B in a mass ratio of 1-10:1-5, and stabilizer A is selected from at least one of propylene glycol alginate, pectin, sodium carboxymethyl cellulose and soybean polysaccharide; the stabilizer B comprises 0-10% citrus fiber, 1-20% calcium carbonate and the remainder of auxiliary materials by mass percentage, and the auxiliary materials are selected from at least one of sodium carboxymethyl cellulose, seaweed dietary fiber, konjac flour, carrageenan and gellan gum. The above yogurt uses additives such as citrus fiber or other stabilizers, auxiliary materials, etc. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a low-temperature yogurt containing seaweed dietary fiber, which completely replaces various additives to play a thickening and stabilizing role, and a preparation method thereof.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: to provide a low-temperature yogurt containing seaweed dietary fiber, which is prepared from raw materials in the following weight ratios: dairy products: 80-92 parts; sugar: 5-10 parts; seaweed dietary fiber: 0.16-0.3 parts; fermentation bacteria: 0.1-0.12 parts.

[0006] Furthermore, in the above-mentioned low-temperature yogurt containing seaweed dietary fiber, the dairy product is raw cow's milk, goat's milk, whole milk powder, skim milk powder or whey powder.

[0007] Furthermore, in the above-mentioned low-temperature yogurt containing seaweed dietary fiber, the sugar is sucrose, maltitol, sorbitol, erythritol, isomaltulose, isomalt, xylitol, arabinose, allulose, lactitol, sucralose, monk fruit extract, steviol glycoside, acesulfame potassium, neotame or adventitone.

[0008] Furthermore, in the above-mentioned low-temperature yogurt containing seaweed dietary fiber, the fermentation bacteria are selected from: one or more of Lactobacillus bulgaricus, Bifidobacterium lactis, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides, Lactococcus lactis subsp. diacetyl, Lactococcus lactis subsp. lactis, and Lactobacillus rhamnosus.

[0009] Furthermore, in the above-mentioned low-temperature yogurt containing seaweed dietary fiber, the dairy product is raw cow's milk; the dairy product is raw cow's milk; the sugar is sucrose; and the fermentation bacteria are Lactobacillus bulgaricus and Streptococcus thermophilus in a mass ratio of 2:3.

[0010] Another technical solution provided by the present invention is: providing a method for preparing the above-mentioned low-temperature yogurt containing seaweed dietary fiber, comprising the following steps: S1: Weigh each raw material according to its weight ratio; S2: adding the preheated dairy product into the mixture, mixing and stirring to obtain a mixed material; the mixture is a mixture of sugar and seaweed dietary fiber; S3: homogenizing the obtained mixed material; S4: sterilizing the product obtained in step S3; S5: The product obtained in step S4 is cooled to 37-40° C.; S6: adding fermentation bacteria to the product obtained in step S5 and fermenting for 7-8 hours. After fermentation, refrigerating the obtained sample at 2-4° C. to obtain low-temperature yogurt containing seaweed dietary fiber.

[0011] Furthermore, the preparation method of the low-temperature yogurt containing seaweed dietary fiber specifically comprises the following steps: S1: Weigh each raw material according to its weight ratio; S2: preheating the dairy product to 55-60° C., adding the mixture, and mixing and stirring to obtain a mixed material; the mixture is a mixture of sugar and seaweed dietary fiber; S3: Use a high-speed shearing dispersing homogenizer to homogenize the obtained mixed material at 55-60°C and 10000-12000r for 5-8min; S4: The product obtained in step S3 is heated to 85-90°C for sterilization for 10-15 minutes; S5: The product obtained in step S4 is cooled to 37-40° C.; S6: After adding the fermentation bacteria to the product obtained in step S5, the temperature is controlled at 40°C-43°C and the humidity is maintained at 75-80%, and the fermentation is performed for 7-8 hours. After the fermentation is completed, the obtained sample is refrigerated at 2-4°C to obtain a low-temperature yogurt containing seaweed dietary fiber.

[0012] Furthermore, the method for preparing the low-temperature yogurt containing seaweed dietary fiber further comprises the steps of: S7: Stir the low-temperature yogurt obtained in step 6 evenly, with a mechanical stirring speed of 50-60 r / min, and stir for 2-3 min; S8: aseptically filling the stirred low-temperature yogurt; S9: refrigerate the low-temperature yogurt obtained in step S8 at 4°C to 8°C to stop its continued fermentation, and the refrigeration time is 12 to 14 hours.

[0013] The beneficial effects of the present invention are: the present invention uses sea extract TM (Seaweed dietary fiber) is used as a raw material to replace agar, pectin, gelatin, modified starch, CMC, gellan gum and other food additives commonly used in yogurt as a thickener and stabilizer for yogurt. It not only improves the taste and texture of yogurt, effectively increases the water holding rate and viscosity of yogurt, avoids whey precipitation, but also supplements dietary fiber, promotes intestinal health, and increases the nutritional value of the product. At the same time, it can also meet the current needs of consumers and customers for "clean label" products. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a graph showing the water holding rate of low-temperature yogurt according to a specific embodiment of the present invention; Figure 2 This is a viscosity measurement diagram of low-temperature yogurt according to a specific embodiment of the present invention; Figure 3 This is a diagram for measuring the pH value of low-temperature yogurt according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0015] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0016] Seaweed TM (Seaweed dietary fiber) refers to: a food raw material obtained from one or more seaweeds through pretreatment, homogenization, enzymolysis, drying, crushing and other processes, with a dietary fiber content of ≥50% (obtained by the processing method of patent application number: 202311760152.7) Yogurt viscosity: refers to the resistance of yogurt to fluid flow under certain conditions (such as temperature and shear rate), and is an important factor affecting the taste and quality of yogurt. Its viscosity is related to the physical and chemical properties of the yogurt, such as the content of milk protein, lactose and other ingredients, calcium ion concentration, pH value, etc.

[0017] Yogurt water holding rate: It is an important indicator to measure the quality and stability of yogurt. It reflects the ability of yogurt to prevent water loss and has a direct impact on the shelf life of yogurt. It mainly reflects the amount of whey precipitation. The calculation formula is: water holding rate = (M3-M1) / (M2-M1)*100; where: the weight of the centrifuge tube is recorded as M1, the weight of yogurt + centrifuge tube is recorded as M2, and the weight after pouring out the precipitated liquid is recorded as M3.

[0018] Yogurt pH value: It is an important index for evaluating the taste of yogurt. The present invention mainly verifies whether different thickening and stabilization changes have an effect on the fermentation of yogurt.

[0019] The seaweed dietary fiber used in the present application can be the seaweed dietary fiber prepared by the Chinese invention with publication number CN117530410. The seaweed dietary fiber used in the specific embodiment of the present invention is prepared as follows: S1. Alkali treatment: Gracilaria was added to tap water, soaked and washed to remove the accompanying mud and shell impurities; the washed seaweed was added to 5% wt of sodium hydroxide solution, heated to 85 degrees, and stirred for 4 hours; S2. Washing: Soak the algae after alkali treatment in tap water, drain the water, repeat until the washing solution is neutral, and soak in clean water for 30 minutes; S3. Bleaching: Soak the algae in a 1%wt sodium hypochlorite solution at room temperature and stir for 30 minutes; S4. Washing: Rinse the bleached algae with tap water until there is no obvious odor; S5. Acidification: Immerse the washed algae in 1% wt room temperature oxalic acid solution and stir for 30 min; S6. Washing: Soak and wash the acidified algae in tap water, repeating the process until it becomes neutral; S7. Grinding and homogenizing: adding the washed and acidified algae into a grinder and grinding and homogenizing until there are no obvious particles; S8. Enzyme hydrolysis: add a certain amount of clean water, heat to 50 degrees, add 1.5% cellulase and 1.5% pectinase, stir and react for 3 hours, then add 1.5% papain and react for 3 hours. After the enzymatic hydrolysis is completed, heat to 95 degrees to inactivate; S9. Drying and crushing: Dry the enzymatic hydrolysate at 60 degrees for one day, and grind it into powder with a crusher to 100 mesh to obtain the sea extract. TM (Seaweed dietary fiber).

[0020] Example 1 A method for preparing low-temperature yogurt containing seaweed dietary fiber comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.08g of seaweed dietary fiber respectively, and mix the sucrose and seaweed dietary fiber evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0021] Example 2 A method for preparing low-temperature yogurt containing seaweed dietary fiber comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.12g of seaweed dietary fiber respectively, and mix the sucrose and seaweed dietary fiber evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0022] Example 3 A method for preparing low-temperature yogurt containing seaweed dietary fiber comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.16g of seaweed dietary fiber respectively, and mix the sucrose and seaweed dietary fiber evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0023] Example 4 A method for preparing low-temperature yogurt containing seaweed dietary fiber comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.3g of seaweed dietary fiber respectively, and mix the sucrose and seaweed dietary fiber evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling. Place it in a refrigerator at 4°C and continue to ripen for about 12 hours to obtain the final product.

[0024] Comparative Example 1 A method for preparing low-temperature yogurt comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose respectively. Add sucrose to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation bacteria (the fermentation bacteria are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation bacteria is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, with a mechanical stirring rate of 50r / min and a stirring time of 3min. Perform aseptic filling. Put it in a refrigerator at 4°C for about 12h to obtain the final product.

[0025] Comparative Example 2 A method for preparing low-temperature yogurt comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.16g of citrus fiber respectively, and mix the sucrose and citrus fiber evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation bacteria (the fermentation bacteria are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation bacteria is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling. Place it in a refrigerator at 4°C and continue to ripen for about 12 hours to obtain the final product.

[0026] Comparative Example 3 A method for preparing low-temperature yogurt comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.16g of imported seaweed powder respectively, and mix the sucrose and imported seaweed powder evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0027] Comparative Example 4 A method for preparing low-temperature yogurt comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.16g of a domestic seaweed powder respectively, and mix the sucrose and domestic seaweed powder evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0028] Comparative Example 5 A method for preparing low-temperature yogurt comprises the following steps: Weigh 91.72g of raw milk according to the formula. Preheat the raw milk to about 60°C. Weigh 8g of sucrose and 0.16g of instant agar respectively, and mix the sucrose and instant agar evenly. Add the sucrose mixture to the preheated raw milk and perform high-speed shearing at 10000r for 5min. After shearing, place it at 90°C for sterilization for about 15min. Then let it stand and cool to 40°C. Weigh 0.12g of mixed fermentation strains (the fermentation strains are Lactobacillus bulgaricus and Streptococcus thermophilus with a mass ratio of 2:3, and the addition amount of the fermentation strains is 0.02dcu / 100ml), inoculate, and then place it in a fermentation box at a temperature of 42°C and a humidity of 78% for fermentation for about 8h. After fermentation, put the sample in a refrigerator at 4°C for about 20min to terminate the fermentation. Stir again, the mechanical stirring rate is 50r / min, and the stirring time is 3min. Perform aseptic filling and place in a refrigerator at 4°C for further post-ripening for about 12 hours to obtain the final product.

[0029] The comparative analysis of the above embodiment and the comparative example is as follows: Example 1: The amount of seaweed dietary fiber added is 0.08%; Example 2: The amount of seaweed dietary fiber added is 0.12%; Example 3: The amount of seaweed dietary fiber added is 0.16%; Example 4: Seaweed dietary fiber added in an amount of 0.3%; Comparative Example 1: Blank (no thickener or stabilizer added); Comparative Example 2: citrus fiber 0.16%; Comparative Example 3: Imported seaweed powder 0.16%; Comparative Example 4: 0.16% of a certain domestic seaweed powder, Comparative Example 5: 0.16% of a certain domestic instant agar.

[0030] Water holding rate determination method: Take about 10g of yogurt into a centrifuge tube and centrifuge for 20 minutes at a centrifugal speed of 4000r / min (centrifugal force: 1750g). After centrifugation, let it stand for 10 minutes, pour out the precipitated liquid, and weigh it. The weight of the centrifuge tube is recorded as M1, the weight of yogurt + centrifuge tube is recorded as M2, and the weight after pouring out the precipitated liquid is recorded as M3. Calculation formula: Water retention rate = (M3-M1) / (M2-M1)*100 Viscosity measurement method: Wait for the yogurt to return to room temperature before testing. Take about 30 ml of yogurt into a 50 ml centrifuge tube, select rotor 3, and rotate at 0.6 rpm for 10 minutes, record the viscosity value, repeat the test 3 times, and take the average value.

[0031] pH value determination method: The pH meter was calibrated before measuring the samples, and the pH value of the yogurt samples was directly measured. Each sample was measured 3 times in parallel, and the average value was taken, with the value retained to 2 decimal places.

[0032] See also Figure 1 , water holding rate is an important indicator to measure the quality and stability of yogurt. It reflects the ability of yogurt to prevent water loss, has a direct impact on the shelf life of yogurt, and avoids the phenomenon of whey precipitation. As can be seen from the above figure, in Examples 1, 2, 3, and 4, the water holding rate is significantly improved with the increase in the amount of seaweed dietary fiber added. When the amount of seaweed dietary fiber added is about 0.16%, there is basically no phenomenon of whey precipitation. Compared with Comparative Example 1, the addition of seaweed dietary fiber in Example 1 can significantly improve the water holding rate of yogurt. Compared with Comparative Examples 2, 3, 4, and 5, Example 3 shows that the addition of seaweed dietary fiber can significantly improve the water holding rate of yogurt under the same thickening, stabilizer / natural dietary fiber / seaweed powder addition amount. At the same time, when the amount of citrus fiber added in Comparative Example 2 exceeds a certain amount, it will significantly affect the taste and flavor of yogurt. The good water-holding performance of yogurt is mainly reflected in the mutual combination of the stabilizer with the protein, milk fat, water and other components in the milk or the ability to improve its stability. As the milk is heated, mechanically stirred, and the pH value changes during the various processing steps of yogurt, the balance between protein, milk fat and water is broken, which will cause the precipitation of water and whey. Adding a stabilizer can avoid this phenomenon. This shows that seaweed dietary fiber can more easily protect the balance between protein, milk fat and water in yogurt.

[0033] See also Figure 2 , seaweed dietary fiber is not only rich in dietary fiber components, but also has thickening and stabilizing effects. As can be seen from the above figure, in Examples 1, 2, 3, and 4, as the amount of seaweed dietary fiber added increases, the viscosity of the yogurt will also increase accordingly in the same proportion, and the viscosity is positively correlated with the amount of seaweed dietary fiber added. Compared with Comparative Example 1, the addition of seaweed dietary fiber in Example 3 has a significant effect on the thickening of yogurt. Compared with Comparative Examples 2, 3, 4, and 5, Example 3 has a better thickening effect of seaweed dietary fiber at the same amount of addition. This shows that components such as protein and fat in yogurt can combine with seaweed dietary fiber to form a tighter network structure system, thereby achieving a better thickening effect.

[0034] See also Figure 3 The pH value of yogurt is an important indicator that has a great influence on the taste of yogurt. The pH value measured in this experiment is mainly to verify the effect of adding seaweed dietary fiber on the fermentation acid production of bacteria. The pH values ​​of yogurt made in the embodiment and the comparative example are both around 4.3, indicating that the addition of seaweed dietary fiber has no effect on the fermentation of bacteria.

[0035] Please refer to Table 1 and Table 2 for the sensory evaluation analysis of the low-temperature yogurt obtained in the above-mentioned embodiment of the present invention and the comparative example.

[0036] Table 1 Sensory evaluation table of low-temperature yogurt

[0037] Table 2 Statistics of sensory evaluation of low-temperature yogurt

[0038] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A low-temperature yogurt containing seaweed dietary fiber, characterized in that: The invention is prepared from the following raw materials in the following weight ratios: 80-92 parts of dairy products; 5-10 parts of sugar; 0.16-0.3 parts of seaweed dietary fiber; and 0.1-0.12 parts of fermentation bacteria.

2. The low-temperature yogurt containing seaweed dietary fiber according to claim 1, characterized in that: The dairy product is raw cow's milk, goat's milk, whole milk powder, skimmed milk powder or whey powder.

3. The low-temperature yogurt containing seaweed dietary fiber according to claim 1, characterized in that: The sugar is sucrose, maltitol, sorbitol, erythritol, isomaltulose, isomalt, xylitol, arabinose, psicose, lactitol, sucralose, monk fruit extract, steviol glycoside, acesulfame potassium, neotame or adventitone.

4. The low-temperature yogurt containing seaweed dietary fiber according to claim 1, characterized in that: The fermentation bacteria are selected from: one or more of Lactobacillus bulgaricus, Bifidobacterium lactis, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides, Lactococcus lactis subsp. diacetyl, Lactococcus lactis subsp. lactis, and Lactobacillus rhamnosus.

5. The low-temperature yogurt containing seaweed dietary fiber according to claim 1, characterized in that: The dairy product is raw cow's milk; the dairy product is raw cow's milk; the sugar is sucrose; and the fermentation bacteria are Lactobacillus bulgaricus and Streptococcus thermophilus in a mass ratio of 2:

3.

6. The method for preparing the low-temperature yogurt containing seaweed dietary fiber according to any one of claims 1 to 5, characterized in that: The steps include: S1: Weigh each raw material according to its weight ratio; S2: adding the preheated dairy product into the mixture, mixing and stirring to obtain a mixed material; the mixture is a mixture of sugar and seaweed dietary fiber; S3: homogenizing the obtained mixed material; S4: sterilizing the product obtained in step S3; S5: The product obtained in step S4 is cooled to 37-40° C.; S6: adding fermentation bacteria to the product obtained in step S5 and fermenting for 7-8 hours. After fermentation, refrigerating the obtained sample at 2-4° C. to obtain low-temperature yogurt containing seaweed dietary fiber.

7. The method for preparing low-temperature yogurt containing seaweed dietary fiber according to claim 6, characterized in that: The specific steps include: S1: Weigh each raw material according to its weight ratio; S2: preheating the dairy product to 55-60° C., adding the mixture, and mixing and stirring to obtain a mixed material; the mixture is a mixture of sugar and seaweed dietary fiber; S3: Use a high-speed shearing dispersing homogenizer to homogenize the obtained mixed material at 55-60°C and 10000-12000r for 5-8min; S4: The product obtained in step S3 is heated to 85-90°C for sterilization for 10-15 minutes; S5: The product obtained in step S4 is cooled to 37-40° C.; S6: After adding the fermentation bacteria to the product obtained in step S5, the temperature is controlled at 40°C-43°C and the humidity is maintained at 75-80%, and the fermentation is performed for 7-8 hours. After the fermentation is completed, the obtained sample is refrigerated at 2-4°C to obtain a low-temperature yogurt containing seaweed dietary fiber.

8. The method for preparing low-temperature yogurt containing seaweed dietary fiber according to claim 7, characterized in that: Also includes the steps: S7: Stir the low-temperature yogurt obtained in step S6 evenly, with a mechanical stirring speed of 50-60 r / min, and stir for 2-3 min; S8: aseptically filling the stirred low-temperature yogurt; S9: refrigerate the low-temperature yogurt obtained in step S8 at 4°C to 8°C to stop its continued fermentation, and the refrigeration time is 12 to 14 hours.

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