Degreased yoghourt and preparation method thereof

Abstract

The invention provides defatted yoghourt and a preparation method thereof. The viscosity of the degreased yoghurt is 2300-2900 mPa.s, the fat content is 1.5 + / -0.2 g / 100g, and the whey separation height is 3-5 mm / 100g. The defatted yoghurt is low in fat content, thick in taste, high in stability and free of whey precipitation.

Description

Technical Field

[0001] The invention relates to a defatted yogurt, in particular to a defatted yogurt and a preparation method thereof, belonging to the field of food. Background Art

[0002] Skim yogurt is a yogurt product made by fermenting skim milk as the raw material. It has a relatively low fat content and a high protein content. It is suitable for providing rich nutrition for people who limit fat intake and pay attention to their body shape.

[0003] However, the milky flavor of yogurt mainly comes from the fat in milk. Since skimmed yogurt contains relatively little fat, its milky flavor is weaker and its taste is thinner than that of full-fat yogurt, resulting in a poor consumer experience.

[0004] Therefore, skimmed yogurt, which retains the milky flavor and rich taste of full-fat yogurt but contains less fat, is expected to fill the market gap. Summary of the invention

[0005] The invention provides a defatted yogurt with low fat content, thick taste, less whey precipitation and good product stability during the shelf life.

[0006] The invention also provides a method for preparing defatted yogurt, which has a simple process flow and is easy to operate; the defatted yogurt prepared by the method has a low fat content, a thick taste within the shelf life, and good product stability.

[0007] The invention provides a defatted yogurt, which has a viscosity of 2300-2900 mPa·s, a fat content of 1.5±0.2 g / 100 g, and a whey separation height of 3-5 mm / 100 g.

[0008] The skim yogurt as described above, wherein the raw materials of the skim yogurt include, by mass percentage: 85%-95% skim raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant;

[0009] The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber;

[0010] The viable count of the fermentation agent is 10 11 -10 12 cfu / g.

[0011] The skimmed yogurt as described above, wherein the emulsified citrus fiber is prepared by at least a method comprising the following process: at 78°C, the citrus fiber and the emulsifier are mixed at 3300 r / min for 7 minutes to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.8.

[0012] The skim yogurt as described above, wherein the emulsifier comprises at least one of mono- and di-glycerol fatty acid esters and sucrose fatty acid esters.

[0013] The skim yogurt as described above, wherein the food adjuvant comprises at least one of a sweetener, jam and a stabilizer.

[0014] In the skim yogurt as described above, the sweetening substance comprises at least one of glucose, white sugar, fructose, fructose syrup, maltose, xylitol, acesulfame potassium, aspartame, sucralose and cyclamate.

[0015] The skim yogurt as described above, wherein the starter comprises at least one of thermophilic Streptococcus, bulgaricus, Bifidobacterium lactis and Lactobacillus rhamnosus.

[0016] The present invention also provides a method for preparing any of the above-mentioned defatted yogurt, comprising the following steps:

[0017] 1) mixing a raw material system including skimmed raw milk and food adjuvants with emulsified citrus fiber to obtain a first material;

[0018] 2) homogenizing and sterilizing the first material to obtain a second material;

[0019] 3) adding a starter to the second material and fermenting, and terminating the fermentation when the fermentation acidity is 70°T to 75°T to obtain the skim yogurt;

[0020] The raw materials of the skimmed yogurt include, by mass percentage, 80%-85% skimmed raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant;

[0021] The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber;

[0022] The viable count of the fermentation agent is 10 11 -10 12 cfu / g.

[0023] The preparation method as described above, wherein the emulsified citrus fiber is prepared by a method comprising at least the following processes: 78, mixing the citrus fiber and the emulsifier at 3300n for 7 minutes to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.8.

[0024] The preparation method as described above, wherein, before step 1), further comprises subjecting the skimmed raw milk to browning treatment.

[0025] The skimmed yogurt provided by the invention has a fat content of 1.5±0.2 g / 100 g within the shelf life, which is significantly lower than the fat content of full-fat yogurt and is suitable for providing rich nutrition to people who limit fat intake and pay attention to their body shape; the skimmed yogurt has a viscosity of 2300-2900 mPa·s and a thick mouthfeel; the whey precipitation height per 100 g of the product is 3-5 mm, the whey precipitation is less, and the product stability is good. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are 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.

[0027] The first aspect of the present invention provides a defatted yogurt having a viscosity of 2300-2900 mPa·s, a fat content of 1.5±0.2 g / 100 g, and a whey precipitation height of 3-5 mm / 100 g.

[0028] The above-mentioned skimmed yogurt is a yogurt product made by fermenting skimmed raw milk as raw material. Its fat content is 1.5±0.2g / 100g, which is significantly lower than the fat content of full-fat yogurt (the fat content is generally ≥4.8g / 100g). While satisfying consumers' appetite, it avoids adding burden to the human body due to high fat. It is suitable for people who limit fat intake and pay attention to their body shape.

[0029] The viscosity of yogurt can be used to characterize the fat and thick taste of the product. The viscosity of the skim yogurt of the present invention is 2300-2900 mPa·s, and the product is thick, indicating that the skim yogurt of the present invention has a fat mouthfeel similar to that of full-fat yogurt, and has a thick mouthfeel.

[0030] The whey precipitation height is 3-5mm / 100g, the whey precipitation is relatively small, and the product stability is good, which in turn helps to improve the flavor and taste of the product.

[0031] The skimmed yogurt of the present invention has a low fat content. On the premise of satisfying the appetite of consumers, it avoids adding burden to the human body due to high fat, and is suitable for people who limit fat intake and pay attention to their body shape. Although the skimmed yogurt has a low fat content, it still has a thick fat taste similar to that of full-fat yogurt, with good taste and good consumer experience. The skimmed yogurt has good stability and less whey precipitation, which is conducive to ensuring the flavor and taste of the product.

[0032] In some embodiments, the raw materials of the above-mentioned skim yogurt include, by weight percentage: 85%-95% skim raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant;

[0033] The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber;

[0034] The viable count of the above fermentation agent is 10 11 -10 12 cfu / g.

[0035] The above-mentioned skimmed raw milk generally refers to skimmed milk that complies with my country's fresh milk purchasing standard GB6914.

[0036] Generally speaking, due to its low fat content, skimmed yogurt has a weak milky flavor, a thin taste, an unstable product system, and easy whey precipitation, which further deteriorates the flavor and taste of skimmed yogurt.

[0037] The inventors found that when citrus fiber and emulsifier are mixed in a mass ratio of (10-15): (0.5-1) at 75-80°C and 3000-3500r / min for 5-8min, the citrus fiber is emulsified and modified to obtain emulsified citrus fiber. By adding 2%-3% of the emulsified citrus fiber to the raw material system of the above-mentioned skimmed yogurt instead of fat, the above-mentioned series of problems caused by low fat content can be effectively solved, the milky flavor and fat-like thick taste of the skimmed yogurt are enhanced, the product viscosity reaches 2300-2900mPa·s, and the flavor and taste of the skimmed yogurt are effectively improved; the emulsified citrus fiber can be used as a stabilizer for the skimmed yogurt system, significantly improving the stability of the skimmed yogurt, avoiding the problem of whey precipitation in the skimmed yogurt product system, and keeping the whey precipitation height of the product at a relatively low level of 3-5mm / 100g.

[0038] The above-mentioned process of emulsifying and modifying the citrus fiber controls the stirring temperature, stirring frequency and stirring time, as well as the mass ratio of the citrus fiber and the emulsifier, so that the above factors are reasonably matched and work synergistically to obtain an emulsified citrus fiber that helps to improve the flavor, taste and stability of skim yogurt.

[0039] The citrus fiber may be commercially available citrus fiber capsule particles.

[0040] The raw materials of the above-mentioned skimmed yogurt include 85%-95% skimmed raw milk and 0.01%-0.02% starter, and the number of live bacteria in the starter is 10 11 -10 12 cfu / g, the fat content of this skimmed yogurt is 1.5±0.2g / 100g and it is rich in protein, which can provide consumers with rich nutrition and avoid the burden of high fat on the body. The product is also rich in live bacteria, which work synergistically with emulsified citrus fiber to help speed up consumers' intestinal motility and improve constipation problems, and has high health value.

[0041] The skimmed yogurt prepared by the above raw material system uses emulsified citrus fiber to replace part of the fat, so that the fat content of the skimmed yogurt is lower and the protein content is higher, which provides consumers with rich nutrition while avoiding the physical burden caused by high fat; the skimmed yogurt has a high viscosity, a strong milky flavor, a harmonious aroma, a delicate and thick taste like fat, and a uniform taste experience; the emulsified citrus fiber can be used as a stabilizer for skimmed yogurt, which can significantly improve the stability of the product and avoid the problem of whey precipitation. The product is milky white, has a more uniform state, and has a more uniform texture.

[0042] Furthermore, the emulsified citrus fiber is prepared by at least the following process: at 78°C, the citrus fiber and the emulsifier are mixed at 3300r / min for 7min to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.8. The emulsified citrus fiber is used to prepare skim yogurt, which can further improve the milk flavor, delicate and thick taste and stability of skim yogurt, making the milk flavor of skim yogurt richer, the aroma coordinated, the taste more delicate and thick, the taste uniform, the experience better, and the product stability better.

[0043] The emulsifier includes at least one of mono- and di-glycerol fatty acid esters and sucrose fatty acid esters, which makes the product have a strong milk flavor, harmonious aroma, delicate and thick taste, uniform taste, less whey precipitation and higher stability.

[0044] The above-mentioned food adjuvant includes at least one of sweeteners, jam, and stabilizers, which is beneficial to further increase the sweetness, flavor and stability of the above-mentioned skim yogurt.

[0045] Furthermore, the jam can be a sucrose-free jam, which is conducive to obtaining a sucrose-free skim dessert yogurt, increasing the sweetness of the skim yogurt while avoiding increasing the sugar content, thereby reducing the burden on the body.

[0046] The stabilizer includes at least one of sodium carboxymethyl cellulose, carrageenan, konjac gum, gellan gum, xanthan gum, modified starch, pectin, agar, locust bean gum and guar gum.

[0047] It is understandable that the above-mentioned sweeteners include at least one of glucose, white sugar, fructose, fructose syrup, maltose, xylitol, acesulfame potassium, aspartame, sucralose and cyclamate. The raw materials of the above-mentioned sweeteners are widely available and easy to obtain, and have the advantages of low cost and high cost performance.

[0048] Generally, the mass percentage of the above-mentioned sweetening substances in the above-mentioned skim yogurt raw materials is generally 3-10%, so that the skim yogurt has moderate sweetness and sourness, thereby obtaining a skim dessert yogurt.

[0049] In addition, when the above-mentioned sweetening substances include sucralose and acesulfame potassium, the mass ratio of the two can be (0.05-1): (0.3-1.2), which can significantly improve the sweet-sour ratio of skim yogurt, and the product has moderate sweetness and sourness.

[0050] Fructose syrup can be used as a substitute for white sugar or sucrose, ensuring sweetness while reducing the health burden of large amounts of sucrose. When the above-mentioned sweetener includes fructose syrup, its mass percentage is generally 2%-4%, so that the sweetness of skim yogurt reaches a moderate level, presenting a moderate sweet and sour taste, giving consumers a pleasant enjoyment.

[0051] When the above-mentioned fermentation agent includes at least one of thermophilic Streptococcus, Bulgarian Lactobacillus, Bifidobacterium lactis and Lactobacillus rhamnosus, it is beneficial to improve the flavor and taste of skimmed yogurt, and can also make the product have a higher number of live bacteria, which is beneficial to the health of the human intestinal flora and has a higher health value.

[0052] The second aspect of the present invention provides a method for preparing the defatted yogurt of the first aspect, comprising the following steps:

[0053] 1) mixing a raw material system including skimmed raw milk and food adjuvants with emulsified citrus fiber to obtain a first material;

[0054] 2) homogenizing and sterilizing the first material to obtain a second material;

[0055] 3) adding a starter to the second material and fermenting, and terminating the fermentation when the fermentation acidity is 70°T to 75°T to obtain the above-mentioned skimmed yogurt;

[0056] The raw materials of the above-mentioned skimmed yogurt include, by mass percentage, 85%-95% skimmed raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant;

[0057] The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber;

[0058] The viable count of the above fermentation agent is 10 11 -10 12 cfu / g.

[0059] In order to fully mix the various raw materials in the above step 1), the raw materials may be mixed and then stirred at 55° C. for 25 minutes to promote sufficient interaction between the raw materials.

[0060] The purpose of the above homogenization is to prevent the fat from floating up, and the homogenization pressure can be 30 / 180bar.

[0061] The purpose of the above sterilization treatment is to kill miscellaneous bacteria and prevent them from affecting the fermentation of the starter. The sterilization conditions are generally as follows: the sterilization temperature is 95°C and the sterilization time is 300s.

[0062] It is understandable that in the above step 3), the second material should be cooled before adding the fermentation agent, generally cooled to 40-43°C, on the one hand to avoid the temperature of the second material after the above sterilization treatment being too high and unsuitable for the survival of the fermentation agent; on the other hand, adjusting the temperature of the second material to a temperature suitable for the survival and fermentation of the fermentation agent is beneficial to improving the activity of the fermentation agent, thereby improving the fermentation speed and quality.

[0063] The present invention does not impose any particular limitation on the fermentation temperature, and the appropriate fermentation temperature may be determined according to the type of leavening agent.

[0064] The inventors found that when citrus fiber and emulsifier are mixed in a mass ratio of (10-15): (0.5-1) at 75-80°C and 3000-3500r / min for 5-8min, the citrus fiber is emulsified and modified to obtain emulsified citrus fiber, and the emulsified citrus fiber is added into the raw material system of skim yogurt at a mass percentage of 2%-3%. Specifically, the raw material system includes 85%-95% skim raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant. The emulsified citrus fiber can effectively replace fat, solving the problems of skim yogurt having weak milk flavor and thin taste due to its low fat content, unstable product system, easy precipitation of whey, and further deterioration of the flavor and taste of skim yogurt.

[0065] The preparation method has a simple process and is easy to operate. The skim yogurt obtained by the preparation method has a fat content of 1.5±0.2g / 100g and rich protein content, which can provide consumers with rich nutrition while avoiding the increase of body burden due to high fat. The product contains rich live bacteria, which cooperates with the emulsified citrus fiber to help accelerate the intestinal peristalsis of consumers and improve constipation problems, and has high health value. The viscosity of the skim yogurt reaches 2300-2900mPa·s, the product has a strong milky flavor, a harmonious aroma, and a delicate and thick taste like fat. In addition, the emulsified citrus fiber can be used as a stabilizer for the skim yogurt system, significantly improves the stability of the skim yogurt, avoids the problem of whey precipitation, and keeps the whey precipitation height of the product at 3-5mm / 100g.

[0066] Degassing is also required before homogenization in the above step 2) in order to avoid cavitation and damage to the homogenizing equipment.

[0067] In the actual production process, the system after adding the starter in step 3) above needs to pass through a sterile filtration device into a nitrogen-filled fermentation tank for fermentation.

[0068] It is understandable that in the actual production process, the above preparation method also includes filling. Filling and sealing need to be carried out in a closed aseptic filling device, and nitrogen is filled in the filling machine to ensure that the filling process will not cause bacteria contamination to the product. Generally, the filled yogurt is placed in a refrigerated state at 6°C for ripening to obtain the filled skim yogurt.

[0069] Furthermore, the emulsified citrus fiber is prepared by at least the following process: at 78°C, the citrus fiber and the emulsifier are mixed at 3300r / min for 7min to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.8. The emulsified citrus fiber is used to prepare skim yogurt, which can further improve the flavor, taste and stability of skim yogurt, making the milk flavor of skim yogurt richer, the aroma more coordinated, the taste more delicate and thick, the taste more uniform, the experience better, and the product stability better.

[0070] In order to increase the flavor and mouthfeel of the skim yogurt, before step 1), the skim raw milk is further subjected to browning treatment.

[0071] In some embodiments, the raw materials of the above-mentioned skimmed yogurt also include white sugar, and the browning process is: after adding glucose to the skimmed raw milk, browning at 130°C for 10 minutes to obtain a brown skimmed milk base, and then replacing the skimmed raw milk with the above-mentioned brown skimmed milk base in step 1).

[0072] It can be understood that during the above-mentioned browning process, the mass ratio of skimmed raw milk and glucose can be 460:1, which is beneficial to improving the browning effect and better improving the flavor and taste of the product.

[0073] Hereinafter, the defatted yogurt of the present invention and the preparation method thereof are described in more detail through specific embodiments.

[0074] Example 1

[0075] A defatted yogurt of the present embodiment includes the following raw materials of quality:

[0076] 929.63g skim milk, 20g emulsified citrus fiber, 0.01g thermophilic streptococcus, 0.01g bulgaricus lactobacillus, 30g fructose syrup, 0.05g sucralose, 0.3g acesulfame potassium, 20g sugar-free jam;

[0077] The method for preparing the above-mentioned defatted yogurt comprises the following steps:

[0078] 1) at 75° C., mixing citrus fiber microcapsule particles and mono- and di-glycerol fatty acid esters, and stirring at 3000 r / min for 5 min, wherein the mass ratio of the citrus fiber microcapsule particles to the mono- and di-glycerol fatty acid esters is 10:0.5, and the masses of the citrus fiber microcapsule particles and the mono- and di-glycerol fatty acid esters are 20 g and 1 g, respectively, to obtain emulsified citrus fiber;

[0079] 2) skimmed milk, high fructose corn syrup, sucralose, acesulfame potassium, sucrose-free dessert jam and the emulsified citrus fiber are mixed, and stirred at 55° C. for 25 minutes to obtain a first material;

[0080] 3) The first material is sequentially degassed at 65° C. and 18 MPa, homogenized at 30 / 180 bar, sterilized at 95° C. for 300 s, and cooled to 40-43° C. to obtain a second material;

[0081] 4) thermophilic streptococcus and bulgaricus lactobacillus are added to the above-mentioned second material, and enter into a fermentation tank that is charged with nitrogen through an aseptic filtration device, ferment at 43 ℃, stop fermentation when the fermentation acidity is 70 ° T ~ 75 ° T, fill and seal in a closed filling machine charged with nitrogen, and ripen at 6 ℃ of refrigeration to obtain the above-mentioned defatted yogurt.

[0082] Example 2

[0083] This embodiment is basically the same as Embodiment 1, except that:

[0084] 1) In the raw materials, 929.15g skim milk and 20g emulsified citrus fiber were replaced with 919.15g brown skim milk base and 30g emulsified citrus fiber;

[0085] 2) In the preparation method, in step 2), before mixing the raw materials, 2 g of glucose was added to 920 g of skim milk, and browned at 130° C. for 10 min to obtain a brown skim milk base, and 919.15 g of the brown skim milk base was used to replace the skim milk in Example 1.

[0086] Example 3

[0087] This embodiment is basically the same as Embodiment 1, except that:

[0088] In the preparation method, the mixing conditions in step 1) are replaced by 80° C., 3500 r / min, 8 min with 75° C., 3000 r / min, 5 min.

[0089] Example 4

[0090] This embodiment is basically the same as Embodiment 1, except that:

[0091] In the preparation method, step 1) replaces mono- and di-glycerol fatty acid esters with sucrose fatty acid esters.

[0092] Example 5

[0093] This embodiment is basically the same as Embodiment 1, except that:

[0094] In the preparation method, the mass ratio of the citrus fiber microcapsule particles to the mono- and di-glycerol fatty acid esters in step 1 is 10:1.

[0095] Example 6

[0096] This embodiment is basically the same as Embodiment 1, except that:

[0097] In the preparation method, the mass ratio of the citrus fiber microcapsule particles to the mono- and di-glycerol fatty acid esters in step 1 is 15:0.5.

[0098] Example 7

[0099] This embodiment is basically the same as Embodiment 1, except that:

[0100] In the preparation method, the mass ratio of the citrus fiber microcapsule particles to the mono- and di-glycerol fatty acid esters in step 1 is 15:1.

[0101] Example 8

[0102] This embodiment is basically the same as Embodiment 1, except that:

[0103] In the preparation method, the mixing conditions in step 1) are replaced by 78° C., 3300 r / min, 7 min instead of 75° C., 3000 r / min, 5 min, and the mass ratio of citrus fiber microcapsule particles and mono- and diglycerol fatty acid esters is modified to 12:0.8.

[0104] Example 9

[0105] This embodiment is basically the same as Embodiment 1, except that:

[0106] In the preparation method, the mass ratio of citrus fiber microcapsule particles to mono- and di-glycerol fatty acid esters in step 1) is 25 g:2.

[0107] Comparative Example 1

[0108] This comparative example is basically the same as Example 1, except that:

[0109] The ingredients do not include emulsified citrus fiber, the remainder is made up by skim milk.

[0110] Comparative Example 2

[0111] This comparative example is basically the same as Example 1, except that:

[0112] In the raw materials, 30 g of citrus fiber capsule particles were used to replace 20 g of emulsified citrus fiber; correspondingly, the mass of skimmed milk was reduced by 10 g.

[0113] Comparative Example 3

[0114] This comparative example is basically the same as Example 1, except that:

[0115] In the raw materials, 30 g of citrus fiber capsule particles and 0.5 g of mono- and di-glycerol fatty acid esters are used to replace 20 g of emulsified citrus fiber; accordingly, the mass of skimmed milk is reduced by 10.5 g.

[0116] Comparative Example 4

[0117] This comparative example is basically the same as Example 1, except that:

[0118] The raw materials are replaced with 917.65g whole milk, 30g light cream, 1.5g compound stabilizer (consisting of 0.5g acetylated distarch adipate and 1g agar), 20g dessert jam to replace 929.15g skim milk, 20g emulsified citrus fiber, and 20g sucrose-free dessert jam.

[0119] Comparative Example 5

[0120] This comparative example is basically the same as Example 1, except that:

[0121] In the preparation method, the mixing conditions in step 1) are replaced by 65° C., 2000 r / min, 3 min. with 75° C., 3000 r / min, 5 min.

[0122] Comparative Example 6

[0123] This comparative example is basically the same as Example 1, except that:

[0124] The mass of the emulsified citrus fiber in the raw material is 10 g, and correspondingly, the mass of the skim milk is increased by 10 g.

[0125] Comparative Example 7

[0126] This comparative example is basically the same as Example 1, except that:

[0127] The mass of the emulsified citrus fiber in the raw material is 40 g, and correspondingly, the mass of the skim milk is reduced by 20 g.

[0128] Comparative Example 8

[0129] This comparative example is basically the same as Example 1, except that:

[0130] In the preparation method, the mass ratio of the citrus fiber microcapsule particles to the mono- and di-glycerol fatty acid esters in step 1) is 1:1.

[0131] Comparative Example 9

[0132] The sample of this comparative example is commercially available full-fat dessert yogurt.

[0133] Comparative Example 10

[0134] This comparative example is basically the same as Example 1, except that

[0135] In the preparation method, the mixing condition in step 1) is replaced by 70°C to 75°C.

[0136] Comparative Example 11

[0137] This comparative example is basically the same as Example 1, except that

[0138] In the preparation method, the mixing condition in step 1) is replaced by 85°C instead of 75°C.

[0139] Comparative Example 12

[0140] This comparative example is basically the same as Example 1, except that

[0141] In the preparation method, the mixing condition in step 1) is replaced by 2500 r / min to 3000 r / min.

[0142] Comparative Example 13

[0143] This comparative example is basically the same as Example 1, except that

[0144] In the preparation method, the mixing condition in step 1) is replaced by 4000 r / min instead of 3000 r / min.

[0145] Comparative Example 14

[0146] This comparative example is basically the same as Example 1, except that

[0147] In the preparation method, the mixing condition in step 1) is replaced by 3 min with 5 min.

[0148] Comparative Example 15

[0149] This comparative example is basically the same as Example 1, except that

[0150] In the preparation method, the mixing condition in step 1) is replaced by 10 min for 5 min.

[0151] Comparative Example 16

[0152] This comparative example is basically the same as Example 1, except that:

[0153] In the raw materials, 20g of emulsified citrus fiber was replaced with 20g of citrus fiber capsule particles.

[0154] Comparative Example 17

[0155] This comparative example is basically the same as Example 1, except that:

[0156] In the raw materials, 19.05 g of citrus fiber capsule particles and 0.95 g of mono- and di-glycerol fatty acid esters were used to replace 20 g of emulsified citrus fiber.

[0157] Test example

[0158] 1. The following parameters of the above-mentioned examples and comparative examples were tested:

[0159] 1) Viscosity: After the sample was placed at 4°C for 21 days, the viscosity was measured using an Anton Paar MCR302 rheometer. The constant shear rate was 50 1 / s, the data points were collected every 60s 1s / point, the temperature was controlled at 20°C, and the average viscosity value was taken. The specific results are shown in Table 1;

[0160] 2) Fat content: The fat content was tested according to GB 5009.6 standard. The specific results are shown in Table 1;

[0161] 3) Whey precipitation height: After the sample was placed at 4°C for 21 days, the whey precipitation height was measured with 100g of product as the standard. The sample was placed on a horizontal laboratory table and the height from the concave liquid surface of the precipitated whey to the milk base plane was measured with a ruler, which was the whey precipitation height. The specific results are shown in Table 1;

[0162] 4) Sensory evaluation: 30 professional evaluators were randomly selected to evaluate the products based on the product's organizational state (whey separation, viscosity, fineness, texture, etc.), color, flavor, taste, etc. on the 21st day of the shelf life. The sensory evaluation standards are shown in Table 2, and the evaluation results are shown in Table 3.

[0163] 2. Test results

[0164] Table 1 Fat content, viscosity, whey separation height

[0165]

[0166]

[0167] The fat content results in Table 1 show that the fat content of the skim yogurt of the present invention is 1.5±0.2 g / 100 g, which is much lower than the fat content of full-fat yogurt, which is 4.8-5.5 g / 100 g;

[0168] The viscosity results in Table 1 show that by adding emulsified citrus fiber, the viscosity of skim yogurt can be effectively improved, which is similar to the viscosity of normal full-fat dessert yogurt. Since the viscosity of skim yogurt can be used to characterize its fat taste, the present invention significantly improves the taste of skim yogurt by emulsifying citrus fiber, so that it achieves a fat-like thick taste similar to normal full-fat dessert yogurt, while satisfying the appetite of consumers, avoiding the body burden caused by high fat. In addition, if the emulsification temperature and emulsification speed in the preparation process of emulsified citrus fiber do not meet the specified range, it will affect the emulsification effect and cause the product viscosity to be low.

[0169] The results of whey precipitation height in Table 1 show that emulsified citrus fiber can be used as a stabilizer for skim yogurt system, which can improve product stability and avoid the occurrence of whey precipitation problems. Skim yogurt products with added emulsified citrus fiber have similar stability to full-fat dessert yogurt products with added conventional stabilizers, which can maintain the stability of the product system during the shelf life and avoid whey precipitation. When the ratio of citrus fiber: emulsifier (10-15): (0.5-1) is 0.5-1, the product has no whey precipitation problem. When the addition amount of the above two raw materials exceeds this range, the product will have whey precipitation problems, which does not meet the product development requirements.

[0170] Table 2 Sensory evaluation standards

[0171]

[0172] Table 3 Sensory evaluation results

[0173]

[0174]

[0175]

[0176]

[0177] Table 3 sensory evaluation results show:

[0178] The skimmed yogurt of Examples 1-9 has good texture, taste and flavor, no whey precipitation, rich milk flavor, harmonious aroma, delicate and thick taste, moderate sweetness and sourness, and uniform taste;

[0179] Comparing Examples 1-9 with Comparative Examples 1-17, it can be seen that the following factors may affect the sensory evaluation of the product:

[0180] 1) Whether the citrus fiber is emulsified: Comparing Examples 1-9 with Comparative Examples 2, 3, 16 and 17, the raw materials of the skim yogurt include citrus fiber that is not emulsified. The skim yogurt has a thin taste and whey precipitation, which affects the shelf life stability of the product;

[0181] 2) Whether to add emulsified citrus fiber: Comparing Examples 1-9 with Comparative Example 1, the products without adding emulsified citrus fiber and only adding emulsifier have a thin taste and uneven taste. At the same time, a large amount of whey is precipitated in the product, which does not meet the product development requirements;

[0182] 3) Preparation process conditions of emulsified citrus fiber: Comparing Examples 1-9 with Comparative Examples 5, 10-15, the emulsification process conditions are 75-80°C for stirring, 3000-35000 r / min for stirring time of 5-8 min, the product has a strong milky flavor, a harmonious aroma, no whey precipitation, a delicate and thick taste, and moderate sweetness and sourness. If this process range is exceeded, the product state and flavor do not meet the development requirements;

[0183] 4) Addition amount of citrus fiber: Comparing Examples 1-9 with Comparative Examples 6-7, when the addition amount of emulsified citrus fiber is 20-30 g / kg, the product has a strong milky flavor, a harmonious aroma, no whey precipitation, a delicate and thick taste, and moderate sweetness and sourness. If the addition amount exceeds this range, the product state and flavor do not meet the development requirements;

[0184] 5) Mass ratio of citrus fiber to emulsifier: Comparing Example 1 with Comparative Example 8, when the ratio of citrus fiber to emulsifier is (10-15): (0.5-1), the product has a strong milky flavor, a harmonious aroma, no whey precipitation, a delicate and thick taste, and a moderate sweetness and sourness. If the addition amount exceeds this range, the product state and flavor do not meet the development requirements;

[0185] 6) Emulsifier type: When the emulsifier is mono- or di-glycerol fatty acid ester or sucrose fatty acid ester, the product has a strong milky flavor and no whey precipitation, meeting the product development needs.

[0186] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A skim yogurt, characterized in that: Its viscosity is 2300-2900 mPa·s, its fat content is 1.5±0.2 g / 100 g, and its whey precipitation height is 3-5 mm / 100 g.

2. The skim yogurt according to claim 1, characterized in that: The raw materials of the skimmed yogurt include, by mass percentage, 85%-95% skimmed raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant; The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber; The viable count of the fermentation agent is 10 11 -10 12 cfu / g.

3. The skim yogurt according to claim 2, characterized in that: The emulsified citrus fiber is prepared by a method comprising at least the following process: at 78° C., the citrus fiber and the emulsifier are mixed at 3300 r / min for 7 minutes to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.

8.

4. The skim yogurt according to claim 2 or 3, characterized in that: The emulsifier includes at least one of mono- and di-glycerol fatty acid esters and sucrose fatty acid esters.

5. The skim yogurt according to any one of claims 2 to 4, characterized in that: The food adjuvant comprises at least one of a sweetener, jam and a stabilizer.

6. The skim yogurt according to claim 5, characterized in that: The sweetener includes at least one of glucose, white sugar, fructose, fructose syrup, maltose, xylitol, acesulfame potassium, aspartame, sucralose and cyclamate.

7. The skim yogurt according to claim 6, characterized in that: The fermentation agent includes at least one of thermophilic streptococcus, bulgaricus lactobacillus, bifidobacterium lactis and lactobacillus rhamnosus.

8. A method for preparing the defatted yogurt according to any one of claims 1 to 7, characterized in that: The following steps are involved: 1) mixing a raw material system including skimmed raw milk and food adjuvants with emulsified citrus fiber to obtain a first material; 2) homogenizing and sterilizing the first material to obtain a second material; 3) adding a starter to the second material and fermenting, and terminating the fermentation when the fermentation acidity is 70°T to 75°T to obtain the skim yogurt; The raw materials of the skimmed yogurt include, by mass percentage, 80%-85% skimmed raw milk, 2%-3% emulsified citrus fiber, 0.01%-0.02% starter, and the remainder is food adjuvant; The emulsified citrus fiber is prepared by a method comprising at least the following steps: mixing citrus fiber and an emulsifier at 3000-3500 r / min for 5-8 min at 75-80° C., wherein the mass ratio of the citrus fiber to the emulsifier is (10-15): (0.5-1), to obtain the emulsified citrus fiber; The viable count of the fermentation agent is 10 11 -10 12 cfu / g.

9. The preparation method according to claim 8, characterized in that: The emulsified citrus fiber is prepared by a method comprising at least the following process: at 78° C., the citrus fiber and the emulsifier are mixed at 3300 r / min for 7 minutes to obtain the emulsified citrus fiber, wherein the mass ratio of the citrus fiber to the emulsifier is 12:0.

8.

10. The preparation method according to claim 8 or 9, characterized in that: Before step 1), the method further includes subjecting the skimmed raw milk to browning treatment.

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