Yoghourt ice cream stabilizing system, yoghourt ice cream and preparation method of yoghourt ice cream

Abstract

The invention belongs to the technical field of frozen food, and discloses a yoghourt ice cream stable system, yoghourt ice cream and a preparation method thereof. The stable system comprises dietary fibers, protein glutaminase and glutamine transaminase, and the stable system can improve the taste fineness and stability of the yoghourt ice cream and ensure that the ice cream product has high puffing rate and melting resistance. The yoghourt ice cream comprises the stable system, the raw materials of the yoghourt ice cream are simple and easy to obtain, the product taste and texture are good, and the system stability is high. According to the preparation method disclosed by the invention, the yogurt ice cream is prepared in a manner of fermenting all base materials, a traditional preparation process of adjusting acid without fermentation or adding part of fermented yogurt is replaced, and a full fermentation process of the materials is added, so that on one hand, molecules of casein are connected with each other to form a more stable three-dimensional network structure, and the stability of the product is improved; on the other hand, the adverse effects of lactose precipitation and melting resistance caused by lactose are greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of frozen food, and in particular to a yogurt ice cream stabilizing system, yogurt ice cream and a preparation method thereof. Background Art

[0002] Yogurt ice cream is a delicious and healthy food with rich flavors and nutritional value. Compared with traditional ice cream, yogurt ice cream usually contains lower fat and sugar, which can meet consumers' pursuit of healthy diet; it is also rich in probiotics, which helps to improve intestinal health and enhance immunity; and it has rich and diverse flavors, and is usually sold in cups or sticks, which is easy to carry and eat. Under the combined effect of the above factors, yogurt ice cream is becoming more and more popular among consumers. Although yogurt ice cream has many advantages, most of them use artificial acidification or secondary ingredients to adjust the acidity during the preparation process, but the above two methods still have certain defects, resulting in the effect of yogurt ice cream is not ideal.

[0003] Artificially acidified yogurt ice cream has a large difference in taste restoration, and the large amount of acid added during artificial acidification can easily cause product protein denaturation, and more stabilizers need to be added to ensure the stability and melting resistance of the ice cream product under lower acidity conditions. This results in uneven product quality and a not-so-pure taste.

[0004] Secondary batching type yogurt ice cream is mainly acidified by adding part of fermented yogurt, and the ingredients need to be prepared separately, which means that half of the base material has to bear the entire stabilizer system, which needs to have strong acid resistance and high requirements for the stability system of yogurt ice cream. In addition, the use of secondary batching may also form a freezing point difference due to the incompatibility of fermented yogurt and other ingredients in the secondary batching, resulting in the formation of large ice crystals in the product, which greatly affects the taste and quality of the product. Summary of the invention

[0005] The purpose of the present invention is to provide a yogurt ice cream stabilizing system, which can improve the taste and stability of yogurt ice cream and ensure that the ice cream product has a strong expansion rate and anti-melting property.

[0006] The technical solution adopted to achieve the purpose of the present invention is: a yogurt ice cream stabilization system, including dietary fiber and protein glutaminase.

[0007] Furthermore, it also includes glutamine aminotransferase.

[0008] Furthermore, the dietary fiber is citrus fiber, and the weight ratio of citrus fiber to protein glutaminase is (1-3): (0.2-0.5).

[0009] Furthermore, the dietary fiber is citrus fiber, and the weight ratio of citrus fiber, protein glutaminase and glutamine transaminase is (1-3): (0.2-0.5): (0.2-0.5).

[0010] In the present invention, the dietary fiber can be citrus fiber or orange fiber, and citrus fiber is preferred in the present invention. Citrus fiber is a natural dietary fiber extracted from citrus, which can be used as a fat substitute in yogurt ice cream to reduce the fat content in the product, while maintaining or improving the texture and sensory properties of the product, and has good acid resistance, making the product full and silky. Citrus fiber also has gelling, water retention and thermal stability. Using it as a raw material for ice cream yogurt helps to enhance the stability of yogurt ice cream, and can prevent the formation and growth of ice crystals during the production and storage of ice cream, thereby maintaining the delicate taste of the product and extending the shelf life.

[0011] The protein glutaminase (hereinafter referred to as PG enzyme) in the present invention can specifically act on the glutamine group of protein, and is also the first natural food enzyme preparation that can improve the solubility of protein under low pH conditions. The PG enzyme is applied to the yogurt ice cream of the present invention, which can hydrolyze the glutamine residues of the protein side chains in the raw materials to generate ammonia and protein-L-glutamate without acting on other ingredients in the yogurt ice cream; and the PG enzyme also has the effects of improving protein utilization, improving emulsification, improving odor and reducing allergenicity. The invention can improve protein utilization, emulsification and reduce the rough taste caused by milk powder by adding PG enzyme to the yogurt ice cream raw materials, so that the product tastes more delicate and smooth.

[0012] The combined effect of PG enzyme and citrus fiber can further optimize the taste and texture of yogurt ice cream. Specifically, PG enzyme improves the solubility and emulsification of protein, while citrus fiber increases the consistency and smoothness of the product. The two complement each other, making yogurt ice cream more delicate and taste better. In addition, PG enzyme enhances the water holding capacity of the product by optimizing the protein structure, while citrus fiber prevents whey precipitation through its water retention performance. The two work together to keep yogurt ice cream of better quality during storage and transportation.

[0013] The glutamine aminotransferase (hereinafter referred to as TG enzyme) in the present invention is a monomeric protein with a molecular weight of about 38,000 and an active center composed of 331 amino groups, which can catalyze intramolecular and intermolecular covalent cross-linking of protein polypeptides, thereby improving the structure and function of proteins, and having significant effects on foaming, emulsification, emulsification stability, thermal stability, water retention and gelling ability, thereby improving the flavor, taste, texture and appearance of food. The invention can improve the expansion rate, stability and anti-melting of the product by adding TG enzyme to the raw materials of yogurt ice cream.

[0014] The TG enzyme and PG enzyme in the present invention work together to significantly improve the structure and function of the protein in the yogurt ice cream, making it more delicate and smooth; and the addition of citrus fiber further enhances the consistency and smoothness of the product, and the synergistic effect of the three improves the taste and texture of the yogurt ice cream. In addition, TG enzyme improves the stability of yogurt ice cream by enhancing the gel strength and emulsification of protein; PG enzyme improves the solubility of protein, reduces precipitation and stratification; the water retention performance of citrus fiber helps prevent ice crystal formation and maintain the delicate taste and stability of the product. After the three work together and cooperate with other raw materials in the yogurt ice cream raw materials, the expansion rate and anti-melting property of the product can be improved.

[0015] Another object of the present invention is to provide a yogurt ice cream, the raw materials of which are simple and easily available, the product taste and texture are good, and the system stability is high.

[0016] The technical solution adopted to achieve another object of the present invention is: a yogurt ice cream, comprising the above-mentioned stabilizing system.

[0017] Furthermore, it also includes a yogurt ice cream base and a leavening agent.

[0018] Furthermore, the yogurt ice cream base includes whole milk powder and / or raw milk, white sugar, cream, maltodextrin and polydextrose.

[0019] In recent years, as consumers' health awareness and understanding of food ingredients continue to increase, the public has begun to pay attention to the health and nutrition of their daily diet. In the context of the public's dietary needs becoming more healthy and rational, "clean labels" with keywords such as "natural", "transparent" and "simple ingredients" have gradually become an important feature for food and beverages to gain public trust. According to a Mintel survey, 86% of Chinese consumers said they would like to see a simpler and easier-to-understand ingredient list. The raw materials in this invention are simple in source, with few additives, green and healthy, and high in nutritional content, which can meet the public's dietary health and nutritional needs.

[0020] The whole milk powder or raw milk, white sugar, cream, maltodextrin and starter in the present invention are all existing common raw materials. Among them, the starter can be selected from the common yogurt starter containing multiple probiotics, such as thermophilic Streptococcus salivarius, Lactobacillus delbrueckii subspecies bulgaricus, Bifidobacterium animalis, etc.

[0021] The polydextrose in the present invention is a water-soluble dietary fiber with a low caloric value and a lower freezing point, which is higher than that of a sucrose solution of the same concentration, and has good shape retention and anti-crystallization properties. When added to yogurt ice cream, it can maintain the necessary volume and improve the texture and taste. In addition, polydextrose in yogurt ice cream also has the effect of enhancing stability, which can reduce the formation of ice crystals, thereby maintaining the delicate taste of the product and extending the shelf life.

[0022] The polydextrose and citrus fiber in the present invention both have the function of improving the taste and texture of the product. Among them, polydextrose can increase the viscosity and smoothness of the food, while citrus fiber can provide a full taste and a fresh flavor. The combination of the two can make the taste of the yogurt ice cream more delicate and smooth while maintaining a certain chewing feeling.

[0023] Another object of the present invention is to provide a method for preparing yogurt ice cream, which is easy to prepare and suitable for large-scale production.

[0024] The technical solution adopted to achieve another object of the present invention is: a method for preparing yogurt ice cream, which specifically comprises the following steps: adding a stabilizing system to the yogurt ice cream base, and then adding a leavening agent for fermentation.

[0025] Furthermore, the fermentation temperature is 40-45°C, and the fermentation time is 6-8h.

[0026] The beneficial effects of the present invention are:

[0027] 1. The PG enzyme and citrus fiber of the present invention work together as a stabilizing system, which can optimize the taste and texture of yogurt ice cream, and can enhance the water holding capacity and water retention performance of the product, so that the yogurt ice cream maintains better quality during storage and transportation.

[0028] 2. The TG enzyme, PG enzyme and citrus fiber in the present invention work together as a stabilizing system, which can make the product more delicate and smooth, further improve the taste and texture of yogurt ice cream, and the three work together with other raw materials in the raw materials to improve the expansion rate and anti-melting property of the product.

[0029] 3. The polydextrose and citrus fiber in the present invention both have the function of improving the taste and texture of the product. The combination of the two can make the taste of the yogurt ice cream more delicate and smooth while maintaining a certain chewing feeling.

[0030] 4. The preparation method of the present invention prepares yogurt ice cream by fermenting all the base materials, replacing the traditional production process of not fermenting and acidifying or adding partially fermented yogurt to increase the full fermentation process of the material. On the one hand, the casein molecules of the preparation method of the present invention will be connected to each other to form a more stable three-dimensional network structure, thereby improving the stability of the product; on the other hand, it also greatly reduces the adverse effects of lactose precipitation and the impact on anti-melting properties caused by lactose.

[0031] 5. The stabilizing system and raw materials of the present invention are natural, transparent, simple in composition, simple in raw materials, less in additives, green and healthy, and high in nutritional content, which can meet the public's dietary health and nutritional needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0033] Figure 1 This is a comparison chart of the effects of PG enzyme and citrus fiber on particle size.

[0034] Figure 2 This is a comparison chart of the effects of PG enzyme and citrus fiber on product texture.

[0035] Figure 3 This is a comparison chart of the impact of the TG stabilization system on product stability.

[0036] Figure 4 It is the trend diagram of G′ of each group changing with temperature.

[0037] Figure 5 This is the trend diagram of G" of each group changing with temperature.

[0038] Figure 6 This is a comparison chart of the effect of the stabilization system on the product expansion rate.

[0039] Figure 7 This is a comparison chart of the impact of the stabilization system on the product's resistance to melting.

[0040] Figure 8 This is a comparison chart of the sensory scores of each group.

[0041] In the above figures, the “*” mark indicates p<0.05; the “**” mark indicates p<0.01; the “***” mark indicates p<0.001; and the “****” mark indicates p<0.0001. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Example 1

[0045] A yogurt ice cream comprises the following raw materials in parts by weight per 1000 parts by weight: 150 parts of whole milk powder, 70 parts of white sugar, 180 parts of light cream, 45 parts of maltodextrin, 0.03 parts of leavening agent, 35 parts of polydextrose, 2 parts of citrus fiber, and the balance is water.

[0046] The preparation method of the yogurt ice cream specifically comprises the following steps:

[0047] Step S1, ingredients, weigh the corresponding weight portions of raw materials, add citrus fiber to the yogurt ice cream base, and then sequentially perform material preparation, homogenization and sterilization. In this step, the material preparation step is: add 53°C warm water to the yogurt ice cream base system and stir for 15 minutes until it is uniform. The homogenization step is: heat the yogurt ice cream base system to 65°C and then homogenize at 18Mpa. The sterilization method adopts pasteurization.

[0048] Step S2, inoculation and fermentation, adding a fermentation agent to the yogurt ice cream base system for fermentation. Specifically, adding enzymes and fermentation bacteria to the homogenized and sterilized yogurt ice cream base, and fermenting at 42° C. for 7 hours.

[0049] In this step, the starter is a fermentation strain, and one or a combination of two or more of Streptococcus salivarius thermophilus subsp., Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium animalis, Lactobacillus acidophilus, and Lactobacillus delbrueckii thermophilus can be selected. In this embodiment, Lactobacillus delbrueckii thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are preferably compounded in a ratio of 1:1.

[0050] Step S3, sequentially shearing, homogenizing, cooling, aging and puffing the fermented system. Specifically, the fermented curd is stirred and sheared, and then homogenized again to make the viscosity of the yogurt ice cream base reach an appropriate value, cooled to 4°C, slowly stirred, and aged for more than 2 hours. Then, the homogenized freezing machine is frozen and puffed, and the puffing rate is 30-60%, preferably 45%.

[0051] Embodiment 2-4

[0052] Compared with Example 1, Examples 2-4 are different mainly in the types of raw materials and the preparation methods. The specific differences are as follows.

[0053] 1. Raw materials

[0054] The products of Examples 2-4 include the following raw materials in every 1000 parts by weight: 150 parts of whole milk powder, 70 parts of white sugar, 180 parts of light cream, 45 parts of maltodextrin, 0.03 parts of leavening agent, and 35 parts of polydextrose.

[0055] Based on the above raw materials, the main differences of Examples 2-4 are as follows:

[0056] Example 2 also includes 0.3 parts of PG enzyme, but does not include citrus fiber, and the balance is water;

[0057] Example 3 includes 0.3 parts of PG enzyme, 2 parts of citrus fiber, and the balance is water;

[0058] Example 4 includes neither PG enzyme nor citrus fiber, and the balance is water.

[0059] For the convenience of comparison, this example further distinguishes the raw materials of the above examples 1-4 into a comparison table, as shown in the following Table 1.

[0060] Table 1 Comparison of raw materials for Examples 1-4

[0061] raw material Example 1 Example 2 Example 3 Example 4 Whole milk powder / serving 150 150 150 150 White sugar / part 70 70 70 70 Cream / portion 180 180 180 180 Maltodextrin / serving 45 45 45 45 Polydextrose / serving 35 35 35 35 Leavening agent / serving 0.03 0.03 0.03 0.03 Citrus fiber / serving 2 / 2 / PG enzyme / serving / 0.3 0.3 /

[0062] 2. Preparation method

[0063] The preparation methods of Examples 2-4 are almost the same as those of Example 1, except that the raw materials added in step S1 and the enzymes added in step S3 are different. The specific differences between Examples 1-4 are as follows:

[0064] In Example 1, the stabilizing system added to the yogurt ice cream base in step S1 contains citrus fiber; and in the fermentation process of step S2, only fermentation bacteria are added without adding enzymes.

[0065] In Example 2, the stabilizing system added to the yogurt ice cream base in step S1 does not contain citrus fiber; and PG enzyme is added at the same time as the fermentation bacteria is added during the fermentation process in step S2.

[0066] In Example 3, the stabilizing system added to the yogurt ice cream base in step S1 contains citrus fiber; and PG enzyme is added at the same time as the fermentation bacteria is added during the fermentation process in step S2.

[0067] In Example 4, the stabilizing system added to the yogurt ice cream base in step S1 does not contain citrus fiber; and in the fermentation process of step S2, only fermentation bacteria are added without adding enzymes.

[0068] The raw materials of Examples 1-4 are processed according to their corresponding processing steps to obtain yogurt ice cream products.

[0069] 1. Detect the particle size of the products of Examples 1-4

[0070] The samples corresponding to Examples 1-4 were respectively taken for particle size detection, so as to obtain the influence relationship between PG enzyme and citrus fiber on particle size. The samples taken in Examples 1-4 were named sample A1, sample A2, sample A3 and sample A4, respectively, and the detection results of samples A1-A4 are as follows: Figure 1 shown.

[0071] (Note: After getting the test results, in order to facilitate comparison, Figure 1 In the bar graph, samples A1-A4 are not plotted in order, but in the order of sample A1, sample A3, sample A2, and sample A4. )

[0072] according to Figure 1 The results show that compared with sample A4 without PG enzyme, the particle size of sample A2 with PG enzyme added is significantly reduced, and the difference is significant (p < 0.001), which indicates that the addition of PG enzyme significantly reduces the particle size of the product and the product tastes more delicate.

[0073] In addition, comparing sample A1 and sample A3, sample A1 only added citrus fiber, and sample A3 added citrus fiber and PG enzyme at the same time. The same analysis showed that adding PG enzyme can significantly reduce the particle size of the product, and the difference is significant (p < 0.01). However, it may be because the particle size of citrus fiber is coarse, and the particle size after PG enzyme reduction is slightly higher than that of sample A3.

[0074] In addition, the particle size has an important influence on the stability, appearance, rheological properties and performance of the final product of the emulsion. The smaller the particle size of the emulsified particles, the more stable the emulsion system formed, which indicates that the addition of PG enzyme can improve the stability of the emulsion.

[0075] 2. Test the texture of the product in Example 1.4

[0076] The samples corresponding to Examples 1-4 were respectively taken for texture testing to obtain the influence relationship between PG enzyme and citrus fiber on texture. The samples taken in Examples 1-4 were named sample B1, sample B2, sample B3 and sample B4, and the test results of samples B1-B4 are as follows: Figure 2 shown.

[0077] according to Figure 2 The results show that the blank group sample B4 without adding PG enzyme and citrus fiber has the highest hardness, reaching 87.97g, reflecting a harder taste; while the texture of sample B1 after adding citrus fiber is significantly reduced (p < 0.01), which indicates that adding citrus fiber can improve product texture.

[0078] Sample B3 is a sample B1 with PG enzyme added. Figure 2 It was found that the addition of PG enzyme could significantly reduce the texture and roughness of citrus fiber (p < 0.001).

[0079] In addition, compared with sample B2 to which only PG enzyme was added, and sample B4 to which no system (i.e., citrus fiber and PG enzyme) was added, sample B3, by adding PG enzyme at the same time as citrus fiber, could significantly improve the product texture and significantly improve the product taste.

[0080] Example 5

[0081] Compared with Example 1, Example 5 mainly differs in the types of raw materials and the preparation method. The specific differences are as follows.

[0082] 1. Raw materials

[0083] The products of Example 5 and Example 1 include the following raw materials in parts by weight per 1000 parts by weight of raw materials: 150 parts of whole milk powder, 70 parts of white sugar, 180 parts of light cream, 45 parts of maltodextrin, 0.03 parts of leavening agent, 35 parts of polydextrose, and 2 parts of citrus fiber.

[0084] Based on the above raw materials, the main differences between Example 5 and Example 1 are as follows:

[0085] Example 1 includes neither PG enzyme nor TG enzyme, and the balance is water;

[0086] Example 5 further includes 0.3 parts of PG enzyme, 0.3 parts of TG enzyme, and the balance is water.

[0087] For the convenience of comparison, this example further distinguishes the raw materials of the above examples 1-5 to make a comparison table (since the amounts of whole milk powder, white sugar, cream, maltodextrin, leavening agent and polydextrose are the same, only the differences are shown in the table), as shown in Table 2 below.

[0088] Table 2 Comparison of raw materials for Examples 1-5

[0089] raw material Example 1 Example 2 Example 3 Example 4 Example 5 Citrus fiber / serving 2 / 2 / 2 PG enzyme / serving / 0.3 0.3 / 0.3 TG enzyme / portion / / / / 0.3

[0090] 2. Preparation method

[0091] The preparation method of Example 5 is almost the same as that of Example 1, except that the enzyme added in step S3 is different. The specific differences between Example 1 and Example 5 are as follows:

[0092] In Example 1, in the fermentation process of step S2, only fermentation bacteria are added without adding enzymes.

[0093] In Example 5, PG enzyme and TG enzyme are added at the same time as the fermentation bacteria are added during the fermentation process of step S2.

[0094] The raw materials of Example 5 are processed according to the corresponding processing steps to obtain yogurt ice cream products.

[0095] 1. Testing the Clarity Index of the Products of Examples 1-5

[0096] The samples corresponding to Examples 1-5 were respectively taken for clarification index detection, so as to compare the role of TGase in improving product stability. The samples taken in Examples 1-5 were named sample C1, sample C2, sample C3, sample C4 and sample C5, and the test results of samples C1-C5 are as follows: Figure 3 shown.

[0097] according to Figure 3 As can be seen from the results, the stability of each group was tested in the present invention. It was found that the sample C4 without adding a stabilizing system had the highest clarification index, indicating that its stability was the worst. The stability of the remaining groups was significantly improved compared with sample C4 (p < 0.001, p < 0.0001). This shows that adding citrus fiber and PG enzyme can improve product stability, and the effect of using citrus fiber and PG enzyme at the same time is more obvious. This may be because citrus fiber is separated from citrus fruits and has strong acid resistance, so it is appropriate to use it as an emulsifying stabilizer for yogurt ice cream.

[0098] In addition, TG has better stability when used in combination with citrus fiber and PG enzyme. The addition of TG enzyme in sample C5 significantly improves the stability compared with sample C3 (p < 0.0001). This may be due to the combined effect of enzyme and citrus fiber, which improves the stability of the product.

[0099] 2. Test the rheological properties of the product in Example 1.5

[0100] The samples corresponding to Examples 1-5 were respectively taken for rheological property testing, and the rheological properties of the samples in Examples 1-5 were specifically tested at -10°C to 10°C, so as to clarify the gel properties of the stabilizing system and its mechanism of action in helping the product to improve stability. The samples taken in Examples 1-5 were named Sample D1, Sample D2, Sample D3, Sample D4 and Sample D5, respectively.

[0101] The present invention uses a rheometer to compare the elastic modulus G' of each group of samples in the range of -10℃-10℃. G' represents the ability of the material to rebound to its original shape when subjected to dynamic force. The lower the G', the softer the material and the worse its ability to resist deformation. The higher the G', the higher the strength of the gel and the better its ability to fully recover its shape. The test results of samples D1-D5 are as follows: Figure 4 shown.

[0102] according to Figure 4 The results show that, as a whole, the G' of each group changes slightly with decreasing temperature, and the curve is relatively gentle, which indicates that as the temperature decreases, the gelation process of each group progresses slowly or the gel strength is not high, which reflects that the temperature has little effect on the viscosity of the product, and the viscosity of the system is relatively stable. In addition, there are obvious differences in the elastic strength of the G' gels of each group of samples D1-D5. The G' value of sample D4 without a stabilizing system is the largest, indicating that its tissue state is the hardest; sample D3 is significantly reduced after adding PG enzyme and citrus fiber, and sample D5 is the entire stabilizing system (i.e., citrus fiber, PG enzyme and TG enzyme), and its G' value is the smallest, which indicates that the system of sample D5 with citrus fiber, PG enzyme and TG enzyme added is the softest and has the best taste.

[0103] 3. Test the viscosity modulus of the product in Example 1.5

[0104] The corresponding samples of Examples 1-5 were respectively tested for the viscosity modulus (i.e., G″ value), where G″ describes that the material cannot recover its shape after the pure stress is removed, which is related to the liquid behavior of the gel and allows the gel to deform and flow to a certain extent during the injection process. The present invention names the samples taken from Examples 1-5 as Sample E1, Sample E2, Sample E3, Sample E4, and Sample E5, respectively, and the specific test results of Samples E1-E5 are shown in Table 5 below.

[0105] according to Figure 4The results show that the trend of G″ and the values ​​of each group are the same as the trend of G′. The G″ value of sample E4 without adding the system is the highest, and the G″ value of sample E5 with adding the complete stable system (i.e. citrus fiber, PG enzyme and TG enzyme) is the lowest, which indicates that the system of sample E5 with citrus fiber, PG enzyme and TG enzyme added has a refreshing and delicate taste.

[0106] 4. Test the expansion rate of the product in 3.5

[0107] Example 3 includes a stabilizing system, and the stabilizing system includes citrus fiber and PG enzyme

[0108] In Example 4, no stabilizing system was added;

[0109] Example 5 comprises a stabilizing system, and the stabilizing body comprises citrus fiber, PG enzyme and TG enzyme.

[0110] The samples corresponding to Examples 3-5 were respectively taken for expansion rate test, so as to test the influence of the stabilization system on the expansion rate of the product. The samples taken from Examples 3-5 were named as Sample F1, Sample F2 and Sample F3, and the expansion rate of Samples F1-F3 was measured respectively.

[0111] Take a certain volume of ice cream slurry before freezing and an equal volume of finished ice cream, weigh their masses respectively, and calculate the expansion rate of ice cream using the formula:

[0112]

[0113] Specific measurement results such as Figure 6 shown.

[0114] (Note: After getting the test results, in order to facilitate comparison, Figure 6 In the bar graph, samples F1-F3 are not plotted in order, but in the order of sample F2, sample F1, and sample F3.)

[0115] according to Figure 6 The results show that compared with sample F2 without adding a stabilizing system, the puffing of yogurt ice cream products in the group of sample F1 with PG enzyme and citrus fiber increased significantly (p < 0.001), which may be related to the combined action of citrus fiber and PG enzyme. Because both citrus fiber and PG enzyme have certain emulsification properties, and PG enzyme improves the state of protein, it can increase the contact of yogurt ice cream base with more air during freezing and puffing, thereby increasing the puffing rate. On the other hand, the addition of TG in sample F3 also brings a small increase in the puffing rate (p < 0.05), which may be because after TG enzyme acts on protein, it increases the foaming property of protein, thereby increasing the puffing rate.

[0116] 5. Testing implementation 3.5 Melting rate of products

[0117] Example 3 includes a stabilizing system, and the stabilizing system includes citrus fiber and PG enzyme

[0118] In Example 4, no stabilizing system was added;

[0119] Example 5 comprises a stabilizing system, and the stabilizing body comprises citrus fiber, PG enzyme and TG enzyme.

[0120] The samples corresponding to Examples 3-5 were respectively taken for melting rate test, so as to test the influence of the stabilization system on the melting rate of the product. The samples taken from Examples 3-5 were named as Sample G1, Sample G2 and Sample G3, and the expansion rate of Samples G1-G3 was measured respectively.

[0121] The samples of Examples 3-5 were hardened at -39°C for 24 hours and then taken out of the mold. A certain mass of ice cream products were placed on the screen and melted in an oven at 25°C. The time when the first drop of ice cream dripped was recorded and recorded as M. 0 After 150 minutes, record the mass of ice cream dripping, that is, the mass of ice cream melted, and calculate the melting rate of ice cream by the following formula:

[0122]

[0123] Specific measurement results such as Figure 7 shown.

[0124] (Note: After getting the test results, in order to facilitate comparison, Figure 7 In the bar graph, samples G1-G3 are not plotted in order, but in the order of sample G3, sample G1, and sample G2.)

[0125] according to Figure 7 The results show that sample G2 without the addition of a stabilizing system melts the fastest, with the first drop melting time being 23.0% faster than sample G1 (p < 0.01) and 34.3% faster than sample G3 (p < 0.01), and the differences are significant.

[0126] In addition, the present invention tests the melting rate of each group of samples. Compared with sample G2 without adding a stabilizing system, the melting resistance of sample G1 is increased by 21.1% (p < 0.001), and the melting resistance of sample G3 is increased by 31.6% (p < 0.001).

[0127] In addition, compared with sample G1, sample G3 with additional TG enzyme added had an anti-melting property improved by 10.9% (p < 0.05) compared with sample G1, which indicates that the stable system formed by citrus fiber, PG enzyme and TG enzyme has a significant effect on the anti-melting property of yogurt ice cream products and helps to improve the anti-melting property.

[0128] 6. Conduct sensory evaluation on products implemented in 3-5

[0129] Example 3 includes a stabilizing system, and the stabilizing system includes citrus fiber and PG enzyme

[0130] In Example 4, no stabilizing system was added;

[0131] Example 5 comprises a stabilizing system, and the stabilizing body comprises citrus fiber, PG enzyme and TG enzyme.

[0132] The samples corresponding to Examples 3-5 were respectively taken for sensory evaluation. The samples taken from Examples 3-5 were named as Sample H1, Sample H2 and Sample H3, and the sensory evaluation was performed on Samples H1-H3 respectively.

[0133] The samples of Examples 3-5 were placed in a -18°C freezer for 24 hours before being taken out. Ten evaluators who were familiar with ice cream products and had undergone sensory training were invited to score the ice cream according to the sensory evaluation criteria in Table 3. The average score was calculated after removing the highest and lowest scores. Finally, the total sensory score was calculated, and the samples were ranked according to preference.

[0134] Table 7 Sensory evaluation standards for yogurt ice cream

[0135]

[0136]

[0137] The sensory evaluation of samples H1-H3 was carried out from four dimensions: viscosity, smoothness, melting in the mouth, and granularity, and samples H1-H3 were scored according to the standards. The specific sensory results are as follows: Figure 8 shown.

[0138] (Note: After getting the test results, in order to facilitate comparison, Figure 8 In the bar graph, samples H1-H3 are not plotted in order, but in the order of sample H2, sample H1, and sample H3.)

[0139] according to Figure 8 The results show that, from the perspective of the four dimensions, sample H2 without the addition of a stabilizing system scored lower than sample H1 and sample H3, which also reflects the poor taste of sample H2. In terms of viscosity and smoothness, sample H3 with the addition of TG enzyme is better than sample H1, while sample H1 is better than sample H3 in terms of melt-in-the-mouth and granularity, which indicates that TG enzyme and PG enzyme affect the taste of the product at different levels, and have a greater impact on the overall taste of the product.

[0140] Based on the above embodiments and test results, it can be concluded that the yogurt ice cream stabilizing system, yogurt ice cream formula and preparation process provided by the present invention are important for developing a new type of yogurt ice cream with a clean label, and the produced product can maintain a pure fermented taste, a delicate and smooth texture and good anti-melting properties, which is of great significance to the development of yogurt ice cream products.

[0141] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the scope of the present invention should be included in the protection scope of the present invention.

Claims

1. A yogurt ice cream stabilization system, characterized in that: Includes dietary fiber and protein glutaminase.

2. The yogurt ice cream stabilizing system according to claim 1, characterized in that: Including transglutaminase.

3. The yogurt ice cream stabilizing system according to claim 1, characterized in that: The dietary fiber is citrus fiber, and the weight ratio of citrus fiber to protein glutaminase is (1-3): (0.2-0.5).

4. The yogurt ice cream stabilizing system according to claim 2, characterized in that: The dietary fiber is citrus fiber, and the weight ratio of citrus fiber, protein glutaminase and glutamine transaminase is (1-3): (0.2-0.5): (0.2-0.5).

5. A yogurt ice cream, characterized in that: The stabilizing system comprises the stabilizing system according to any one of claims 1 to 4.

6. The yogurt ice cream according to claim 5, characterized in that: Also included is a yogurt ice cream base and a starter culture.

7. The yogurt ice cream according to claim 6, characterized in that: The yogurt ice cream base comprises whole milk powder and / or raw milk, white granulated sugar, cream, maltodextrin and polydextrose.

8. The yogurt ice cream according to claim 6 or 7, characterized in that: The fermentation agent comprises one or a combination of two or more of Streptococcus salivarius thermophilus subspecies, Lactobacillus delbrueckii subspecies bulgaricus, Bifidobacterium animalis, Lactobacillus acidophilus and Lactobacillus delbrueckii thermophilus.

9. A method for preparing the yogurt ice cream as claimed in claims 5 to 8, characterized in that: The specific steps include: A stabilizing system is added to the yogurt ice cream base, and then a fermentation agent is added for fermentation.

10. The method for preparing yogurt ice cream according to claim 9, characterized in that: The fermentation temperature is 40-45°C and the fermentation time is 6-8 hours.

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