阅读说明：本技术 一种含巧克力爆珠的常温酸奶及其制备方法 (Normal-temperature yoghourt containing chocolate popping beads and preparation method thereof ) 是由 孙颜君 王磊 刘振民 徐致远 苏米亚 莫蓓红 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种含巧克力爆珠的常温酸奶及其制备方法,该常温酸奶包括以下质量百分比的原料：生牛乳80～82％、果胶0.068～0.108％、琼脂0.085～0.135％、结冷胶0.009～0.045％、淀粉6.8～9％、发酵剂0.003～0.008％、白砂糖3.4～7.2％、乳蛋白强化物0.255～0.44％、香精0～0.09％和含巧克力爆珠的果味酱2.054～9.38％。淀粉为玉米淀粉、木薯淀粉以及马铃薯淀粉中的一种或多种；发酵剂包括保加利亚乳杆菌和嗜热链球菌。生牛乳中蛋白含量≥3.0wt％,乳糖含量≥3.0wt％,非脂乳固体含量≥8.1wt％。本发明的常温酸奶含巧克力爆珠,为消费者提供可以咀嚼的酸奶产品,给予消费者健康和方便的全新体验。(The invention discloses normal-temperature yoghourt containing chocolate pops and a preparation method thereof, wherein the normal-temperature yoghourt comprises the following raw materials in percentage by mass: 80-82% of raw milk, 0.068-0.108% of pectin, 0.085-0.135% of agar, 0.009-0.045% of gellan gum, 6.8-9% of starch, 0.003-0.008% of leavening agent, 3.4-7.2% of white granulated sugar, 0.255-0.44% of milk protein fortifier, 0-0.09% of essence and 2.054-9.38% of fruit jam containing chocolate popping beads. The starch is one or more of corn starch, cassava starch and potato starch; the leavening agent comprises Lactobacillus bulgaricus and Streptococcus thermophilus. The protein content in raw milk is more than or equal to 3.0 wt%, the lactose content is more than or equal to 3.0 wt%, and the non-fat milk solid content is more than or equal to 8.1 wt%. The normal-temperature yoghourt contains chocolate popping beads, provides a chewable yoghourt product for consumers, and provides the consumers with a brand-new healthy and convenient experience.)

1. The normal-temperature yoghourt containing the chocolate pops is characterized by comprising the following raw materials in percentage by mass: 80-82% of raw milk, 0.068-0.108% of pectin, 0.085-0.135% of agar, 0.009-0.045% of gellan gum, 6.8-9% of starch, 0.003-0.008% of leavening agent, 3.4-7.2% of white granulated sugar, 0.255-0.44% of milk protein fortifier, 0-0.09% of essence and 2.054-9.38% of fruit jam containing chocolate popping beads.

2. The chocolate popsicle-containing room temperature yogurt according to claim 1, wherein the starch is one or more of corn starch, tapioca starch and potato starch;

the leavening agent comprises Lactobacillus bulgaricus and Streptococcus thermophilus.

3. The room-temperature yogurt containing chocolate pops according to claim 1, wherein the raw milk contains not less than 3.0 wt% of protein, not less than 3.0 wt% of lactose, and not less than 8.1 wt% of nonfat milk solids.

4. The room-temperature yogurt containing chocolate pop beads as claimed in claim 1, wherein the fruit-flavored sauce containing chocolate pop beads contains 30-50% of pop beads, 30-40% of soluble solids and 3.8-4.3 of pH.

5. A method for preparing room-temperature yoghourt containing chocolate popping beads according to any one of claims 1 to 4, wherein the method for preparing the room-temperature yoghourt comprises the following steps:

s1: uniformly mixing the pre-sterilized raw milk with white granulated sugar, pectin, agar, gellan gum, starch and lactoprotein fortifier to obtain a mixed solution;

s2: homogenizing, sterilizing and cooling the mixed solution obtained in the step S1, adding essence and an inoculated starter, and fermenting to obtain a yogurt base material;

s3: and (4) demulsifying the yogurt base material obtained in the step (S2), performing secondary sterilization, mixing the sterilized yogurt base material with the sterilized fruit-flavored sauce containing the chocolate pops, and filling to obtain the chocolate-popping-bead-containing fruit-flavored sauce.

6. The preparation method of normal-temperature yoghourt containing chocolate-popping beads according to claim 5, wherein in the step S1, the pre-sterilization is ultra-high-temperature instant sterilization, the pre-sterilization temperature is 135-137 ℃, and the pre-sterilization time is 3-5S.

7. The method for preparing room-temperature yogurt containing chocolate pops according to claim 5, wherein in step S2, the homogenization is a two-stage homogenization, the pressure of the first-stage homogenization is 200-250 bar, the pressure of the second-stage homogenization is 30-80 bar, and the temperature of the first-stage homogenization and the temperature of the second-stage homogenization are both 65-70 ℃;

in the step S2, pasteurization is carried out, a tubular sterilization mode is adopted, the sterilization temperature is 90-95 ℃, the time is 3-7 min, and the temperature is cooled to 42-45 ℃.

8. The normal-temperature yoghourt containing the chocolate pops according to claim 5, wherein in the step S2, the fermentation time is 6-8 h, and the acidity at the fermentation end point is 75-90 degrees T.

9. The normal-temperature yoghourt containing the chocolate pops according to claim 5, wherein in the step S3, the yoghourt base material is pasteurized, the sterilizing temperature is 70-80 ℃, and the sterilizing time is 10-40S.

10. The method for preparing room-temperature yogurt containing chocolate pop beads according to claim 5, wherein in the step S3, the sterilization temperature of the fruit-flavored sauce containing chocolate pop beads is 100-115 ℃, and the sterilization time is 20-30S.

Technical Field

The invention belongs to the technical field of fermented foods, and particularly relates to normal-temperature yoghourt containing chocolate popping beads and a preparation method thereof.

Background

Since the introduction of the Mosleian brand of the Guangming Dairy industry, various domestic dairy enterprises have been simulated, and the normal-temperature yogurt product occupies a relatively large market share in the Chinese dairy market in recent years. At present, the product extends from original taste to various flavors and contains real vegetable, fruit and grain particle products, the homogenization is serious, and how to further carry out product innovation and lead the next consumption potential of the product is a problem of deep thinking of each dairy enterprise.

In recent years, with the development of the snack food market, consumers' enthusiasm for sweets has increased. Especially in younger consumer groups, chocolate becomes the essential "sweet" in their mouth. According to CBNData report, in Tianmao dessert consumption data of three consecutive years from 2017 to 2019, the chocolate sales scale, the number of consumers and the average consumption amount are steadily increased, and the average consumption amount is continuously increased, so that the Tianmao dessert becomes a favorite dessert variety of more people.

Due to the characteristics of low melting point, high fat content and the like of the chocolate raw materials, the combination of the chocolate and the yoghourt has certain technical difficulty, and the chocolate ingredients can be ensured to have certain shape retention in the yoghourt base material only by special treatment. The low-temperature yogurt product 'Joy day' marketed by Ili company is added with jam containing chocolate product particles, the particles are not subjected to high-temperature treatment in jam processing, and the chocolate particles are subjected to special coating treatment to prevent taste change in a yogurt system, but the particles still have the problems of low melting point, incapability of resisting high temperature and the like. The normal temperature yoghourt product containing chocolate is prepared, and the cocoa powder, the chocolate sauce and the like are added in the conventional ingredient process, so that the development of the granular product containing chocolate ingredients has certain technical difficulty.

The invention aims to solve the problems, the formula, the process and the like of the jam and the yoghourt are optimized to prepare the chocolate bead blasting particles, and the chocolate bead blasting particles are used for normal-temperature drinking yoghourt, wherein the chocolate bead blasting particles are rich in flavor and have better blasting feeling, and consumers can taste particles containing real chocolate ingredients while experiencing the smooth mouthfeel of the yoghourt, so that a chewable yoghourt product is provided for the consumers, and the healthy and convenient brand-new experience is provided for the consumers.

Disclosure of Invention

The invention aims to solve the technical problem that the homogeneity of the conventional normal-temperature yoghourt product is serious, the product containing chocolate particles is not applied to the normal-temperature yoghourt, the chocolate bead-popping particles are prepared by optimizing various aspects such as the formula and the process of jam and yoghourt, can resist high-temperature treatment, can be used for normal-temperature drinking yoghourt, ensures the good formability and the taste of the product in the normal-temperature yoghourt, and has good flavor release of the chocolate bead-popping particles within the quality guarantee period of the yoghourt. The method is simple and easy in process and convenient for industrial production, the prepared product can be placed for 6-9 months at normal temperature, the sensory test of the product is excellent, the product microorganism meets the national standard in the quality guarantee period, the product is stable in property, and the phenomena of layered whey precipitation and the like are avoided.

On one hand, the invention provides normal-temperature yoghourt containing chocolate pops, which comprises the following raw materials in percentage by mass: 80-82% of raw milk, 0.068-0.108% of pectin, 0.085-0.135% of agar, 0.009-0.045% of gellan gum, 6.8-9% of starch, 0.003-0.008% of leavening agent, 3.4-7.2% of white granulated sugar, 0.255-0.44% of milk protein fortifier, 0-0.09% of essence and 2.054-9.38% of fruit jam containing chocolate popping beads.

Further, the starch is one or more of corn starch, tapioca starch and potato starch;

the leavening agent comprises Lactobacillus bulgaricus and Streptococcus thermophilus.

Furthermore, the content of protein in raw milk is more than or equal to 3.0 wt%, the content of lactose is more than or equal to 3.0 wt%, and the content of non-fat milk solid is more than or equal to 8.1 wt%.

Further, in the fruit-flavored sauce containing chocolate popping beads, the content of the popping beads is 30-50%, the content of soluble solids is 30-40%, and the pH is 3.8-4.3.

On the other hand, the invention also provides a preparation method of the normal-temperature yoghourt containing the chocolate poplock beads, which comprises the following steps:

s1: uniformly mixing the pre-sterilized raw milk with white granulated sugar, pectin, agar, gellan gum, starch and lactoprotein fortifier to obtain a mixed solution;

s2: homogenizing, sterilizing and cooling the mixed solution obtained in the step S1, adding essence and an inoculated starter, and fermenting to obtain a yogurt base material;

s3: and (4) demulsifying the yogurt base material obtained in the step (S2), performing secondary sterilization, mixing the sterilized yogurt base material with the sterilized fruit-flavored sauce containing the chocolate pops, and filling to obtain the chocolate-popping-bead-containing fruit-flavored sauce.

Further, in step S1, the pre-sterilization is ultra-high temperature instant sterilization, the pre-sterilization temperature is 135-137 ℃, and the time is 3-5S.

Further, in step S2, homogenizing at a first stage at a pressure of 200-250 bar and at a second stage at a pressure of 30-80 bar at a temperature of 65-70 ℃;

in the step S2, pasteurization is carried out, a tubular sterilization mode is adopted, the sterilization temperature is 90-95 ℃, the time is 3-7 min, and the temperature is cooled to 42-45 ℃.

Further, in step S2, the fermentation time is 6-8 h, and the fermentation end point acidity is 75-90T.

Further, in the step S3, the sterilization of the yogurt base material is pasteurization, the sterilization temperature is 70-80 ℃, and the time is 10-40S.

Further, in step S3, the sterilization temperature of the fruit jam containing chocolate pops is 100-115 ℃, and the sterilization time is 20-30S.

The positive progress effects of the invention are as follows:

the preparation method has the advantages of simple process, easy operation and convenient industrial processing production, the chocolate ingredient exploded bead fruit flavor sauce is innovatively added into the yoghourt product, and the chocolate ingredient exploded bead fruit flavor sauce has better shape retention and better flavor release within the shelf life of the normal-temperature yoghourt through the optimization of the formula and the process. The consumer can enjoy the smoothness of the yoghourt and taste the particle product really containing the chocolate ingredients, so that the chewable yoghourt product is provided for the consumer, and the consumer is provided with a brand new health and convenient experience. Opens up a new direction for normal-temperature drinking yoghurt products with serious homogenization. The prepared product can be placed for 6-9 months at normal temperature, the sensory test of the product is excellent, the product microorganism meets the national standard in the quality guarantee period, the product property is stable, and the phenomena of layered whey precipitation and the like are avoided.

Detailed Description

In order to more clearly illustrate the technical solution of the present invention, the technical solution of the present invention will be further illustrated with reference to the following specific embodiments:

one of the technical schemes provided by the invention is as follows:

the normal-temperature yoghourt containing the chocolate pops comprises the following raw materials in percentage by mass: 80-82.001% of raw milk, 0.068-0.108% of pectin, 0.085-0.135% of agar, 0.009-0.045% of gellan gum, 6.8-9% of starch, 0.003-0.008% of leavening agent, 3.4-7.2% of white granulated sugar, 0.255-0.44% of milk protein fortifier, 0-0.09% of essence and 2.054-9.38% of chocolate popping-containing fruit jam.

The starch is one or more of corn starch, tapioca starch, waxy corn 3.4 rice starch and potato starch.

The milk protein fortifier comprises protein powder.

The leavening agent comprises Lactobacillus bulgaricus and Streptococcus thermophilus.

The content of protein in raw milk is more than or equal to 3.0 wt%, the content of lactose is more than or equal to 3.0 wt%, the content of non-fat milk Solid (SNF) is more than or equal to 8.1 wt%, and the titration acidity is less than or equal to 18 DEG T, wherein the contents are the mass percentage of each component in raw milk.

It should be noted that the goat milk or other animal milks can be used alone or in combination to replace raw cow milk.

In the fruit-flavored sauce containing chocolate popping beads, the content of the popping beads is 30-50%, the content of soluble solids is 30-40%, and the pH is 3.8-4.3.

The fruity sauce containing the chocolate pops can be a finished product sold in the market, and can also be prepared by adopting the method of the third technical scheme to the sixth technical scheme.

The second technical scheme provided by the invention is as follows:

a preparation method of normal-temperature yoghourt containing chocolate pops comprises the following steps:

s1: uniformly mixing part of the pre-sterilized raw milk with white granulated sugar, pectin, agar, gellan gum, starch and lactoprotein reinforcement to obtain a mixed solution;

s2: homogenizing, sterilizing and cooling the mixed solution obtained in the step S1, adding essence and an inoculated starter, and fermenting to obtain a yogurt base material;

s3: and (4) demulsifying the yogurt base material obtained in the step (S2), performing secondary sterilization, mixing the sterilized yogurt base material with the sterilized fruit-flavored sauce containing the chocolate pops, and filling to obtain the chocolate-popping-bead-containing fruit-flavored sauce.

In the step S1, part of the raw milk subjected to pre-sterilization is added, preferably, half of the raw milk is added, the pre-sterilization is ultrahigh-temperature instantaneous sterilization, the pre-sterilization temperature is 135-137 ℃, and the time is 3-5S.

Preferably, the material melting temperature in the step S2 is 65-70 ℃, and the material melting time is 20-30 min.

In the step S2, homogenizing at a second stage, wherein the pressure of the first stage homogenizing is 200-250 bar, the pressure of the second stage homogenizing is 30-80 bar, and the temperature of the first stage homogenizing and the second stage homogenizing is 65-70 ℃;

in the step S2, pasteurization is carried out, a tubular sterilization mode is adopted, the sterilization temperature is 90-95 ℃, the time is 3-7 min, and the fermentation is carried out after cooling to 42-45 ℃.

In the step S2, the fermentation time is 6-8 h, and the acidity at the fermentation end point is 75-90T.

In the step S3, the sterilization of the yogurt base material is pasteurization, the sterilization temperature is 70-80 ℃, and the sterilization time is 10-40S.

In the step S3, the viscosity of the fruity sauce before sterilization is 5-8 cm/60S, the content of soluble solids is 30-40%, and the pH is 3.8-4.3; the sterilization temperature of the fruity sauce is 100-115 ℃, and the sterilization time is 20-30 s. The pumping pressure is 0.2-0.6 bar during sterilization, and the viscosity of the sterilized fruit jam is 7-10 cm/60 s.

Preferably, in the processing process of the blasting beads, a screw pump or a rotor pump is adopted for conveying, the conveying speed is 800-1300 kg/h, and the pumping pressure is 0.4-0.8 bar;

preferably, the yogurt base material sterilized in the step S3 and the bead blasting fruity sauce are uniformly mixed and then are subjected to aseptic filling at the temperature of 18-30 ℃, and the bead blasting damage rate in the filled finished product is 18-20%.

In a second aspect, the invention also provides a normal-temperature fermented dairy product containing the bead blasting particles, which is prepared according to the method.

The normal-temperature yoghourt comprises 2.43-2.56% of protein, 2.92-2.97% of fat, 17.84-21.47% of carbohydrate, 200-300 cP of filling viscosity and 4.0-4.4 of final pH, wherein the contents refer to the mass percentage of all the components in the yoghourt.

The viscosity of the yogurt is 260-360 cP after being placed at normal temperature, the fluctuation of the viscosity of the upper layer and the lower layer of the product is small in the process of being placed at normal temperature for 6-9 months, the phenomena of layering and whey separation are avoided, the product is good in texture and flavor in the quality guarantee period, the flavor of the chocolate bead blasting particles is well released, and the chocolate bead blasting particles have good chewing feeling.

The third technical scheme provided by the invention is as follows:

the invention provides a preparation method of chocolate pops, which comprises the following steps:

the method comprises the following steps: placing the bead blasting coating solution in a vibrating screen, and enabling the bead blasting coating solution to circularly flow from the top to the bottom of the vibrating screen;

step two: dripping the center liquid of the blasting beads downwards at the pressure of 0.02-0.08 bar, and condensing the center liquid of the blasting beads dripped in the coating liquid of the blasting beads to form the blasting beads.

Exemplarily, firstly, placing the bead blasting coating solution in a vibrating screen with an inclination angle of 4-5 degrees, wherein the length of the vibrating screen is 2-3 m, and enabling the bead blasting coating solution to continuously flow circularly from the top to the bottom of the vibrating screen through circulation of a rotor pump; then, dripping the center liquid of the blasting beads on the top of the vibrating screen containing the wrapping liquid from a filling head at the pressure of 0.02-0.08 bar; wherein the diameter of the pouring head is 4-6 mm, and the falling distance of the pouring head is 20-30 cm; and (3) quickly condensing the central liquid instilled in the wrapping liquid to form bead blasting particles with the diameter of 5-7 mm, and collecting the bead blasting particles after the wrapping liquid flows from top to bottom on the vibrating screen, namely the prepared bead blasting particles.

The filling head is located at the upper part of the vibrating screen and used for dripping the center liquid of the blasting beads, the diameter of the filling head, the height of the filling head (namely the distance from the filling head to the center liquid of the blasting beads to contact with the solution of the coating of the blasting beads) and the dripping pressure are controlled to adjust the particle size of the center liquid of the blasting beads, and further the particle size of the blasting beads is adjusted.

Specifically, the bead blasting center liquid comprises the following raw materials in percentage by mass: 10-20% of a stabilizer, 5-10% of a sweetener, 5-10% of a chocolate raw material, 3-6% of an edible essence, 0.5-2% of an acidity regulator and water for supplementing to 100%.

The stabilizer mainly comprises modified starch, wherein the starch is physically or chemically modified starch, and the starch source is corn, waxy corn, cassava, potato, wheat, rice, sago and the like.

The sweetener comprises one or more of white granulated sugar, crystalline fructose, lactitol, xylitol and erythritol.

The chocolate raw materials comprise dark chocolate sauce and cocoa powder raw materials.

The edible essence is a substance which is commonly used in food processing and presents a special flavor.

The acidity regulator is one or more of citric acid, tartaric acid, malic acid, lactic acid, acetic acid, carbonic acid and phosphoric acid.

Specifically, the preparation method of the bead blasting center liquid comprises the following steps:

heating water to 40-50 ℃, adding a stabilizer, sweet sugar, a chocolate raw material and edible essence, stirring at 50-100 rpm for 10-20 min, cooling to 20-30 ℃ (the storage time is less than or equal to 15h in the state), adding an acidity regulator, and adjusting the pH value to 3.7-4.2.

Specifically, the bead blasting coating solution comprises the following raw materials in percentage by mass: 0.3-1% of sodium alginate, 0.02-0.06% of gellan gum, 0.2-1.2% of calcium salt and water for supplementing to 100%.

Specifically, the preparation method of the bead blasting coating solution comprises the following steps:

heating water to 70-80 ℃, adding sodium alginate, gellan gum and calcium salt, stirring and circulating at the speed of 800-1000 rpm for 20-30 min, cooling to 20-30 ℃, and cooling to prepare a solution with the viscosity of 100-300 cp.

The fourth technical scheme provided by the invention is as follows:

a chocolate popple prepared by the above preparation method is provided.

The fifth technical scheme provided by the invention is as follows:

the fruity jam comprises the following raw materials in percentage by mass: 0.2-0.4% of pectin, 25-30% of a sweetening agent, 0.5-2% of an acidity regulator, 0-1% of an edible essence, 30-50% of chocolate pops and water for supplementing to 100%.

The acidity regulator is one or more of citric acid, tartaric acid, malic acid, lactic acid, acetic acid, carbonic acid and phosphoric acid.

The sweetener is preferably sucrose and/or a sugar substitute. The sugar substitute is a substance capable of generating sweet taste or enhancing sweet taste and has much lower calorie than sucrose, preferably one or more of aspartame, acesulfame potassium, sucralose, lactitol, xylitol and erythritol.

Preferably, the pectin is a high ester pectin and the water is purified water.

The sixth technical scheme provided by the invention is as follows:

a preparation method of fruity sauce comprises the following steps:

s1: preparing a glue solution: preheating water to 70-80 ℃, adding pectin and a sweetening agent, stirring and circulating at 1000-1400 rpm for 10-15 min, and cooling to 40-45 ℃ to obtain a glue solution;

s2: adding the popping beads into the glue solution, uniformly stirring at 30-60 rpm, adding edible essence and an acidity regulator, regulating the pH value to 3.7-4.2, and obtaining the prefabricated fruit-flavored sauce;

s3: and (3) sterilization and filling: sterilizing the prepared fruity sauce, cooling and filling to obtain the finished product.

Specifically, in S3, the sterilization temperature is 110-115 ℃, the sterilization time is 20-60S, and the temperature is cooled to 30-30 ℃.

Specifically, in S1, the viscosity of the glue at the temperature is 600-800 cp.

And S3, sterilizing by using a tubular sterilizer, feeding by using a screw pump for sterilization, wherein the feeding pressure is 0.4-0.7 bar, the sterilization temperature is 110-115 ℃, and the sterilization time is 20-60S, cooling to 30-30 ℃, and filling into aseptic bags or aseptic tanks for storage.

The prepared fruity sauce contains 28-48% of popping beads, 5-9 cm of viscosity (determined by a Bostwick method), and 25-30% of soluble solids.

The present invention provides a fruity paste product prepared according to the above method. Wherein the total protein and fat content is 0 wt%, the carbohydrate content is 25-30 wt%, the pH value is 3.0-4.5, the net fruit particle content of the chocolate pops is 28-48%, the breakage rate is less than 5%, and the product has a good state and does not have the phenomena of water separation and layering when placed at normal temperature for 6-9 months. The fruity sauce prepared by the invention has high bead blasting uniformity, good flavor release of the central liquid and moderate viscosity and fluidity, and can be directly added into normal-temperature yoghourt products in an aseptic online manner. The stable system of the chocolate popsicle fruity sauce is better compatible with a normal-temperature yoghourt system, the stability of the normal-temperature yoghourt in the quality guarantee period cannot be damaged after a certain amount of the chocolate popsicle fruity sauce is added into the normal-temperature yoghourt, and the particles are in a suspended state in the quality guarantee period of the yoghourt.

The reagents and starting materials used in the present invention are commercially available.

On the basis of the common knowledge in the field, the preferred conditions can be combined randomly to obtain the preferred embodiments of the invention. On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention. On the basis of the common knowledge in the field, the preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

The performance indexes of the raw materials meet the requirements of relevant quality standards. Other materials and equipment not specifically described are commercially available.

Example 1

A normal temperature yoghourt containing chocolate pops comprises the following raw materials:

table 1 raw material ratios of example 1

(1) In the ingredients, the protein content in raw milk is 3.0 wt%, the fat content is 4.0 wt%, the lactose content is 4.5 wt%, and the titration acidity is less than or equal to 18 DEG T. Mixing the above materials, and stirring at 50 deg.C for 17 min;

(2) homogenizing the mixed solution obtained in the step (1) at 50 ℃, wherein the primary homogenizing pressure and the secondary homogenizing pressure are 150bar and 50bar respectively;

(3) pasteurizing the homogenized liquid at 90 deg.C for 3 min;

(4) cooling the liquid obtained in the step (3) to 42 ℃, adding 0.003% of a leavening agent for fermentation, and pumping for demulsification and cooling to 10 ℃ for later use after the pH of the fermentation end point is 4.2 after 7 hours;

(5) performing secondary pasteurization on the fermented milk obtained in the step (4), wherein the sterilization condition is 70 ℃/30s, and cooling to 18 ℃ for later use after sterilization;

(6) the content of the popping beads in the chocolate popping fruit-flavored sauce is 30 percent, the viscosity is 6cm/60s, the content of soluble solids is 40 percent, and the breakage rate of the popping beads in the raw material of the popping fruit-flavored sauce is less than 2 percent. Sterilizing the fruity sauce by using a tubular sterilizer, wherein a sterilizing feeding pump is a screw pump, the temperature is continuously raised to 110 ℃ after the tubular sterilizer is preheated to 80 ℃, the temperature is kept for 20s, the sterilizing feeding pressure is 0.2bar, the temperature is cooled to 18 ℃, the viscosity of the sterilizing sauce is 7cm/60s, a rotor pump is used for conveying chocolate pops into the yoghourt base material prepared in the step (5) at the speed of 800kg/h, and the popping pumping pressure is 0.4 bar. The adding amount of the fruity sauce is 9.38%, the viscosity of the prepared yoghourt is 250cP, the viscosity of the prepared yoghourt is 260cP after the yoghourt is placed at normal temperature for a period of time, the fluctuation of the product viscosity is small in the process of being placed at normal temperature for 9 months, the phenomena of layering, whey precipitation and the like do not exist, and the popping presents better mouthfeel and shape.

The basic indexes of the normal-temperature fermented milk prepared by the method are as follows:

TABLE 2 index for yogurt of example 1

Index (I)	Mass%
		Protein	2.865
Fat	3.5
		Carbohydrate compound	13.938
Total solids content	20.303

Example 2

A normal temperature yoghourt containing chocolate pops comprises the following raw materials:

table 3 raw material ratios of example 2

Raw materials	Addition amount (%)
		Raw milk	81.000
Pectin	0.108
		Agar-agar	0.135
Gellan gum	0.045
		Starch	9.000
Streptococcus thermophilus and lactobacillus bulgaricus	0.008
		White granulated sugar	7.200
Essence	0.090
		Protein powder	0.360
Fruity sauce	2.054
		Total up to	100

A preparation method of normal-temperature yoghourt containing chocolate popping beads comprises the following steps:

(1) uniformly mixing the antibiotic-free milk sterilized at 137 ℃ for 3s with other ingredients except the leavening agent, the essence and the fruity sauce to obtain a mixed solution;

in the ingredients, the protein content in the raw milk is 3.0 wt%, the fat content is 4.0 wt%, the lactose content is 4.5 wt%, and the titration acidity is less than or equal to 18 DEG T. Mixing the above materials, and stirring at 55 deg.C for 20 min;

(2) homogenizing the mixed solution obtained in the step (1) at 60 ℃, wherein the primary homogenizing pressure and the secondary homogenizing pressure are 200bar and 60bar respectively;

(3) pasteurizing the homogenized liquid at 93 deg.C for 5 min;

(4) cooling the liquid obtained in the step (3) to 43 ℃, adding 0.009% of leavening agent for fermentation, reaching the fermentation end point pH of 4.3 after 4 hours, and then pumping for demulsification and cooling to 10 ℃ for later use;

(5) performing secondary pasteurization on the fermented milk obtained in the step (4), wherein the sterilization condition is 75 ℃/25s, and cooling to 18 ℃ for later use after sterilization;

(6) the content of the pure exploded beads of the raw material of the chocolate exploded bead fruity sauce is 40 percent, the viscosity is 6.5cm/60s, the content of soluble solids is 35 percent, and the breakage rate of the exploded beads in the raw material of the fruity sauce is less than 2 percent. Sterilizing the fruity sauce by using a tubular sterilizer, wherein a sterilizing feeding pump is a screw pump, the temperature is continuously raised to 100 ℃ after the tubular sterilizer is preheated to 70 ℃, the temperature is kept for 30s, the sterilizing feeding pressure is 0.4bar, the temperature is cooled to 18 ℃, the viscosity of the sterilized fruity sauce is 8.5cm/60s, a rotor pump is used for conveying chocolate balls to the yoghourt base material prepared in the step (5) at the speed of 1000kg/h, and the pumping pressure of the balls is 0.6 bar. The addition amount of the fruit jam is 2.054%. The prepared yoghourt has the viscosity of 200cP, the viscosity of 230cP after being placed at normal temperature for a period of time, the fluctuation of the viscosity of the product is small in the process of being placed at normal temperature for 9 months, the phenomena of layering, whey precipitation and the like do not exist, and the popping shows good taste and shape.

The basic indexes of the normal-temperature fermented milk prepared by the method are as follows:

table 4 indices for yogurt in example 2

Index (I)	Content%
		Protein	2.755
Fat	3.247
		Carbohydrate compound	19.253
Total solids content	25.255

Example 3

A normal temperature yoghourt containing chocolate pops comprises the following raw materials:

TABLE 5 raw material ratios of example 3

Raw materials	Mass (%)
		Raw milk	82.001
Pectin	0.088
		Agar-agar	0.114
Gellan gum	0.026
		Starch	7.920
Streptococcus thermophilus and lactobacillus bulgaricus	0.005
		White granulated sugar	5.720
Essence	0.044
		Protein powder	0.440
Fruity sauce	3.642
		Total up to	100

A preparation method of normal-temperature yoghourt containing chocolate popping beads comprises the following steps:

(1) uniformly mixing the sterilized raw milk at 137 ℃ for 3s with other ingredients except for a leavening agent, essence and jam to obtain a mixed solution;

in the raw milk in the ingredients, the protein content is 3.0 wt%, the fat content is 4.0 wt%, the lactose content is 4.5 wt%, and the titration acidity is less than or equal to 18 DEG T. Mixing the above materials, and stirring at 60 deg.C for 15 min;

(2) homogenizing the mixed solution obtained in the step (1) at 65 ℃, wherein the primary homogenizing pressure and the secondary homogenizing pressure are respectively 250bar and 80 bar;

(3) pasteurizing the homogenized liquid at 95 deg.C for 7 min;

(4) cooling the liquid obtained in the step (3) to 45 ℃, adding 0.006% of a leavening agent for fermentation, reaching the fermentation end point pH of 4.4 after 6 hours, and then pumping for demulsification and cooling to 10 ℃ for later use;

(5) performing secondary pasteurization on the fermented milk obtained in the step (4), wherein the sterilization condition is 80 ℃/15s, and cooling to 18 ℃ for later use after sterilization;

(6) the pure exploded bead content of the chocolate exploded bead fruity sauce raw material is 50%, the viscosity is 8cm/60s, the content of soluble solids is 30%, and the breakage rate of the exploded beads in the exploded bead fruity sauce raw material is less than 2%. Sterilizing the bead-blasting fruity sauce by using a tubular sterilizer, wherein a sterilizing feeding pump is a screw pump, the temperature is continuously raised to 115 ℃ after the tubular sterilizer is preheated to 90 ℃, the temperature is kept for 15s, the sterilizing feeding pressure is 0.6bar, the temperature is cooled to 18 ℃, the viscosity of the sterilized fruity sauce is 10cm/60s, a rotor pump is used for conveying chocolate beads to the yoghourt base material prepared in the step (5) at the speed of 1300kg/h, and the pumping pressure of the bead-blasting is 0.8 bar. The adding amount of the jam is 3.642%, the viscosity of the prepared yoghourt is 300cP, the viscosity of the yoghourt is 350cP after the yoghourt is placed at normal temperature for a period of time, the fluctuation of the viscosity of the yoghourt is small in the process of placing the yoghourt at normal temperature for 8 months, the phenomena of layering, whey precipitation and the like do not exist, and the popping shows good taste and shape.

The basic indexes of the normal-temperature yoghourt prepared by the method are as follows:

table 6 raw material ratios of example 3

Index (I)	Mass%
		Protein	2.911
Fat	3.347
		Carbohydrate compound	18.941
Total solids content	25.199

Comparative example 1

In the same way as in example 1, when the chocolate exploded bead-containing fruity sauce is sterilized, the peristaltic pump is used as the feeding pump, the breaking rate of the particle size of the exploded beads after the sterilization is 71%, the viscosity of the prepared yoghourt is 593cp, and the phenomena of caking and agglomeration exist in the shelf life.

Comparative example 2

In the same way as example 1, when the temperature of the preheating section is 50 ℃ and the ton is still 110 ℃ when the chocolate popcorn fruit-flavor sauce is sterilized, the machine is stopped by alarming in the sterilizing process.

Comparative example 3

As in example 2, the sterilization process was not continued except that the pressure in the sterilizer was 0.1bar when the chocolate-containing popcorn paste was sterilized.

Comparative example 4

When the sterilization pressure is 1bar and the sterilization speed after sterilization is 54 percent as in example 2 when the chocolate popping fruit flavor sauce is sterilized.

Comparative example 5

In the same way as in example 3, when only the sauce with the flavor of chocolate popping pearls and the sterilized yogurt base material are mixed, the conveying speed is 1500kg/h, the conveying pressure is 1bar, the crushing rate of the sterilized particles is 62 percent, and the viscosity of the prepared yogurt is 684 cp.

Comparative example 6

In the same way as in example 3, only the chocolate pop fruit-containing sauce before sterilization contains 60% of pure pop beads, the viscosity of the sterilized chocolate pop fruit-containing sauce is 4cm/60s, the rupture rate of the pop beads in the prepared yoghourt finished product is 36% after the sterilized chocolate pop fruit-containing sauce and the yoghourt base material are mixed, and the prepared yoghourt product has agglomeration and caking phenomena within the shelf life.