Jam with good adhesion and viscosity, jam yogurt and preparation method thereof

Abstract

The present application provides a jam with good adhesion and viscosity, a jam yogurt and a preparation method thereof, the raw materials of the jam include, in mass percentage, 10-20 wt% of a saccharide substance, 30-50 wt% of fruit particles, 2-7 wt% of a stabilizer, 0.1-1.5 wt% of a calcium salt substance, 0.01-0.5 wt% of an acidity regulator, and the balance of water; wherein the stabilizer includes pectin and / or hydroxypropyl distarch phosphate, and the calcium salt substance includes calcium lactate and / or milk mineral salt. The jam of the present application has good adhesion and viscosity, and the prepared jam yogurt is stable in layering.

Description

Technical Field

[0001] This invention relates to the field of jam and yogurt technology, specifically to a jam and jam yogurt with good adhesion and viscosity, and a method for preparing the same. Background Technology

[0002] In recent years, yogurt consumption has gradually increased, and the types and varieties of yogurt have become increasingly diverse. In the yogurt market, fruit-flavored yogurt is the most abundant product. Fruit not only gives yogurt a refreshing taste, but its rich vitamin content also makes the nutritional value of yogurt more comprehensive. Layered yogurt is a type of yogurt product where yogurt and jam are served in two separate layers. Typically, the bottom layer is jam and the top layer is yogurt, or vice versa. This novel and unique product, with its fruity flavor, is very popular with consumers.

[0003] However, the separation of jam and yogurt can also cause some problems. For example, when filling the upper layer of jam or yogurt, it can impact the lower layer of yogurt or jam, causing them to blend together. This can lead to issues such as color migration of the jam, easy separation of water from the product, and a softer texture. CN107372829B solves the problem of yogurt impacting jam by adjusting the viscosity of the jam and yogurt. However, the yogurt viscosity involved in this technology is between 1500-5000 cp. If the viscosity of the yogurt or other liquid being filled is less than 1500 cp, the impact force on the lower layer of jam during filling is too great, easily breaking up the jam and making it impossible to guarantee a clear and smooth separation between the yogurt and jam. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the purpose of this invention is to provide a jam with good adhesion and viscosity, as well as a layered jam containing the above-mentioned jam, so that the jam and yogurt are stably separated.

[0005] To achieve the above objectives, the present invention provides a jam with good adhesion and viscosity, comprising, by weight percentage: 10-20 wt% sugars, 30-50 wt% fruit pieces, 2-7 wt% stabilizer, 0.1-1.5 wt% calcium salts, 0.01-0.5 wt% acidity regulator, and the balance being water; wherein the stabilizer comprises pectin and / or hydroxypropyl distarch phosphate, and the calcium salts comprise calcium lactate and / or milk mineral salts.

[0006] During the experiment, the inventors discovered that because low-viscosity milk bases more easily penetrate and seep into the gaps between the jam and the container wall, if the jam's adhesiveness is insufficient and it doesn't adhere firmly to the container wall, it will move away from the container wall during filling, resulting in an unclear interface between the jam and yogurt, or even the jam not being visible from the side of the container. While higher-viscosity jams have good resistance to filling impact, their adhesiveness is insufficient. Therefore, this invention designs a suitable stabilizer formula and increases the synergistic effect of calcium salts on the stabilizer, making the jam texture firm, with good impact resistance, and ensuring it adheres tightly to the container wall after filling, preventing it from flowing easily.

[0007] In the above-mentioned jam with good adhesion and viscosity, preferably, the stabilizer is a combination of pectin and hydroxypropyl distarch phosphate, with the amount of pectin being 0.2-2 wt% and the amount of hydroxypropyl distarch phosphate being 2-6 wt% based on the total mass of the raw materials.

[0008] In the above-mentioned jam with good adhesion and viscosity, preferably, the calcium salt is a combination of calcium lactate and milk mineral salt, with the amount of calcium lactate being 0.1-0.5 wt% and the amount of milk mineral salt being 0.05-0.5 wt% based on the total mass of raw materials.

[0009] The jam of the present invention achieves both good adhesion and viscosity by rationally compounding the raw material components of stabilizers and salts and rationally controlling the proportions.

[0010] In the above-mentioned jams with good adhesion and viscosity, preferably, the sugars include at least one of granulated sugar, fructose syrup, crystalline fructose, polydextrose, and resistant dextrin.

[0011] In the above-mentioned jams with good adhesion and viscosity, preferably, the mass percentage of white sugar is 12-18 wt%.

[0012] In the aforementioned jams with good adhesion and viscosity, preferably, the fruit particles include at least one of the following: strawberry, blueberry, raspberry, cranberry, pineapple, mango, lemon, passion fruit, apricot, orange, tangerine, cherry, aloe vera, kiwi, banana, dragon fruit, apple, pear, hawthorn, grape, lychee, durian, pomegranate, mulberry, star fruit, loquat, pomelo, dried plum, coconut jelly, peach, yellow peach, and guava. More preferably, the size of the fruit particles is 3mm×3mm×3mm to 10mm×10mm×10mm.

[0013] The jam described above, which has good adhesion and viscosity, preferably has a viscosity of 2-5 cm at 20°C, as tested with a BOSTWICK viscometer, and more preferably 3.5-4.5 cm.

[0014] The jam with good adhesion and viscosity, as described above, preferably has an adhesion of -200 mJ to -600 mJ, more preferably -300 mJ to -500 mJ, when tested in Normal mode using a BROOKFIELD texture analyzer.

[0015] The present invention also provides a layered jam yogurt containing the above-mentioned jam with good adhesion and viscosity.

[0016] The present invention also provides a method for preparing the above-mentioned layered jam yogurt, which includes the following steps:

[0017] After mixing milk and auxiliary materials, homogenize and sterilize them, and then inoculate them with fermentation bacteria to obtain the milk base to be fermented.

[0018] The milk base to be fermented and the jam with good adhesion and viscosity are layered, packaged, fermented, and finally refrigerated and matured to obtain the layered jam yogurt.

[0019] In the above-mentioned method for preparing layered jam yogurt, preferably, the layered filling method of the milk base to be fermented and the jam is as follows: Figure 1 As shown, first pour jam into one corner of the container, then pour some of the fermentable milk base into the opposite corner of the container, and finally pour the remaining fermentable milk base into the container from the center.

[0020] In addition to optimizing the raw material formula of the jam, this invention also designs a suitable layered filling method to further reduce the impact of the milk base liquid on the jam at the bottom of the container. This results in the jam being relatively intact in one corner of the bottom of the container and forming a good layer boundary with the milk base liquid in the packaging container. This solves the problems of the jam being easily washed away and becoming unclear after low-viscosity liquid is added to the top layer of the jam.

[0021] In the above-mentioned method for preparing layered jam yogurt, preferably, the melting temperature is 70-75℃ and the melting time is 20-35min.

[0022] In the above-mentioned method for preparing layered jam yogurt, preferably, the auxiliary materials include sugars, stabilizers, and emulsifiers.

[0023] In the above-mentioned method for preparing layered jam yogurt, preferably, the homogenization temperature is 60-65℃, the secondary pressure is 20-40 bar, and the total pressure is 180-200 bar.

[0024] In the above-mentioned method for preparing layered jam yogurt, preferably, the sterilization temperature is 95±2℃ and the time is 300s.

[0025] In the above-mentioned method for preparing layered jam yogurt, preferably, the temperature of the fermented milk base is 43±1℃ during filling.

[0026] In the above-mentioned method for preparing layered jam yogurt, preferably, the fermentation temperature is 45±2℃, and the fermentation endpoint is when the acidity reaches 70-90°T.

[0027] In the above-mentioned method for preparing layered jam yogurt, preferably, the post-cold ripening temperature is 4-6℃.

[0028] The above-mentioned method for preparing layered jam yogurt preferably includes the following steps:

[0029] (1) Mixing: Heat the milk to 70-75℃, then dry mix the sugars, stabilizers and emulsifiers into the milk, circulate the mixture for 20-35 minutes, and then cool it down to below 15℃;

[0030] (2) Homogenization and sterilization: The liquid obtained in step (1) is preheated to 60-65℃ and homogenized. The secondary pressure is 20-40 bar and the total pressure is 180-200 bar. Then the homogenized liquid is sterilized at a temperature of 95±2℃ for 300s. After sterilization, the liquid is cooled to below 15℃.

[0031] (3) Inoculation: Add the inoculum to the liquid obtained in step (2), circulate and stir for 5 minutes, and then heat to 43±1℃ to obtain the milk base to be fermented;

[0032] (4) Filling: The jam and the fermentable milk base obtained in step (3) are filled by a layered addition system. First, the jam is poured into one corner of the container. Second, a portion of the fermentable milk base is poured into the container from the opposite corner. Third, the remaining fermentable milk base liquid is poured into the container from the center.

[0033] (5) Packaging and fermentation: Pack the above containers and then carry out fermentation. The temperature of the fermentation room is 45±2℃, and the fermentation endpoint is when the acidity reaches 70-90°T.

[0034] (6) Post-fermentation of finished product: Cool the fermented product to 20-25℃, and then refrigerate at 4-6℃ for 12-24 hours to obtain layered jam yogurt.

[0035] It should be noted that all raw materials used in this invention can be obtained commercially. Any range described in this invention includes the end value and any value between the end values, as well as any sub-range formed by the end value or any value between the end values.

[0036] The technical solution provided by this invention has the following beneficial effects:

[0037] This invention, on the one hand, designs the amount and ratio of stabilizer ingredients such as pectin and modified starch (hydroxypropyl distarch phosphate) in the jam, and adds calcium salts to form a synergistic stabilizing effect with the stabilizers, so that the jam has good adhesion. This ensures that the jam can form a good adsorption force with the container wall after being added to the container, and is not easily wetted by other liquids into the gap between the jam and the container wall, thus preventing the jam from leaving the container wall and moving. On the other hand, it makes the jam have good viscosity, so that the jam is not easily dispersed by the subsequently added liquid after being added to the bottom of the container.

[0038] In another aspect, this invention designs a new layered filling method to further reduce the impact of the milk base liquid (liquids such as milk) on the jam at the bottom of the container, so that the jam is relatively intact in one corner of the bottom of the container and forms a good layer boundary with the milk base liquid in the packaging container, thereby solving the problems of jam being easily washed away and unclear after adding jam to set yogurt. Attached Figure Description

[0039] Figure 1 This is a schematic flowchart of the layered filling method for liquid and jam in this invention.

[0040] Figure 2 A photograph of the jam yogurt prepared in Example 1;

[0041] Figure 3 A photograph of the jam yogurt prepared in Example 2;

[0042] Figure 4 A photograph of the jam yogurt prepared in Example 3;

[0043] Figure 5 A photograph of the jam yogurt prepared for Comparative Example 1;

[0044] Figure 6 A photograph of the jam yogurt prepared in Comparative Example 2;

[0045] Figure 7 A photograph of the jam yogurt prepared for Comparative Example 3;

[0046] Figure 8 A photograph of the jam yogurt prepared in Comparative Example 4;

[0047] Figure 9 A photograph of the jam yogurt prepared in Comparative Example 5;

[0048] Figure 10 A photograph of the jam yogurt prepared in Comparative Example 6;

[0049] Figure 11 A photograph of the jam yogurt prepared in Comparative Example 7;

[0050] Figure 12This is a schematic photograph illustrating the criteria for judging the clarity of the jam in Experiment Example 2. Detailed Implementation

[0051] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0052] Example 1

[0053] This embodiment provides a yellow peach and calamansi jam and the prepared jam yogurt, and the specific preparation method is as follows:

[0054] I. Preparation of Yellow Peach and Calamansi Jam:

[0055] 1. Jam recipe (per 100g):

[0056]

[0057] 2. Preparation method:

[0058] (1) Mix pectin, hydroxypropyl distarch phosphate and some white sugar evenly, add an appropriate amount of water, heat to 50-60℃ and stir for 30 minutes, dissolve and keep warm;

[0059] (2) Add yellow peach and calamansi fruit granules, remaining white sugar, calcium lactate, milk mineral salt, citric acid, and remaining water to the liquid obtained in step (1), and stir for 10 minutes to dissolve.

[0060] (3) Sterilize the liquid obtained in step (2) at a temperature of 89-93℃ for 10 minutes, and then cool it down to 40℃ to prepare yellow peach and mandarin orange jam.

[0061] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam:

[0062] 1) Mixing: Heat the milk to 72°C, then dry mix the sugars, stabilizers and emulsifiers into the milk, circulate the mixture for 35 minutes, and then cool it down to 13°C;

[0063] 2) Homogenization and sterilization: The liquid obtained in step 1) is preheated to 63°C and homogenized. The secondary pressure is 30 bar and the total pressure is 200 bar. Then, the homogenized liquid is sterilized at 95±2°C for 300 seconds. After sterilization, the liquid is cooled to 9°C.

[0064] 3) Inoculation: Add the inoculum to the liquid obtained in step 2), circulate and stir for 5 minutes, then heat to 43±1℃ to obtain the milk base to be fermented;

[0065] 4) Filling: The jam and the milk base to be fermented are filled by a layered addition system. First, the yellow peach and mandarin orange jam prepared in this embodiment is poured into one corner of the container. Second, a portion of the milk base to be fermented is poured into the container from the opposite corner. Third, the remaining milk base to be fermented is poured into the container from the center.

[0066] 5) Packaging and Fermentation: Pack the above containers and then carry out fermentation. The temperature in the fermentation room is 45±2℃. When the acidity of the product reaches 70°T, it is transferred out of the fermentation room to complete the fermentation.

[0067] 6) Post-fermentation maturation: Cool the fermented product to 20-30℃, and then refrigerate at 4-6℃ for 24 hours to obtain the yogurt containing yellow peach and calamansi jam.

[0068] Example 2

[0069] This embodiment provides a yellow peach and calamansi jam and the prepared jam yogurt, and the specific preparation method is as follows:

[0070] I. Preparation of Yellow Peach and Calamansi Jam:

[0071] 1. Jam recipe (per 100g):

[0072]

[0073] 2. Preparation method: Same as in Example 1.

[0074] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1.

[0075] Example 3

[0076] This embodiment provides a yellow peach and calamansi jam and the jam yogurt prepared therefrom. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0077] 1. Jam recipe (per 100g):

[0078]

[0079] 2. Preparation method: Same as in Example 1.

[0080] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1.

[0081] Comparative Example 1

[0082] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0083] 1. Jam recipe (per 100g):

[0084]

[0085] 2. Preparation method: Same as in Example 1.

[0086] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1

[0087] Comparative Example 2

[0088] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0089] 1. Jam recipe (per 100g):

[0090]

[0091] 2. Preparation method: Same as in Example 1.

[0092] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1

[0093] Comparative Example 3

[0094] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0095] 1. Jam recipe (per 100g):

[0096]

[0097] 2. Preparation method: Same as in Example 1.

[0098] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1

[0099] Comparative Example 4

[0100] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0101] 1. Jam recipe (per 100g):

[0102]

[0103] 2. Preparation method: Same as in Example 1.

[0104] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1

[0105] Comparative Example 5

[0106] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0107] 1. Jam recipe (per 100g):

[0108]

[0109] 2. Preparation method: Same as in Example 1.

[0110] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam: Same as Example 1

[0111] Comparative Example 6

[0112] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt. The specific preparation method is as follows: I. Preparation of yellow peach and calamansi jam:

[0113] 1. Jam recipe (per 100g):

[0114]

[0115]

[0116] 2. Preparation method: Same as in Example 1.

[0117] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam:

[0118] The preparation steps are the same as in Example 1, except that the filling method in step 4) is as follows:

[0119] 4) Filling: The jam and fermented milk base are filled using a layered addition system. First, the jam is poured in from one corner of the container. Second, a portion of the liquid is poured into the container from the center. Third, the remaining fermented milk base is poured into the container from the center.

[0120] Comparative Example 7

[0121] This comparative example provides a yellow peach and calamansi jam and the prepared jam yogurt, and the specific preparation method is as follows:

[0122] I. Preparation of layered yogurt with yellow peach and calamansi:

[0123] 1. Jam recipe (per 100g):

[0124]

[0125] 2. Preparation method: Same as in Example 1.

[0126] II. Preparation of Yogurt Containing Yellow Peach and Calamansi Jam:

[0127] The preparation steps are the same as in Example 1, except that the filling method in step 4) is as follows:

[0128] 4) Filling: The jam and the above-mentioned liquid are filled through a layered addition system. First, the jam is poured into one corner of the container. Second, a portion of the milk base to be fermented is poured into the container from the opposite corner. Third, the remaining milk base to be fermented is poured into the container from the opposite corner.

[0129] Experimental Example 1

[0130] This experimental example is used to test the viscosity and adhesiveness of the jams prepared in the above examples and comparative examples.

[0131] Viscosity test method: A BOSTWICK viscometer was used at a temperature of 20℃. After 60 seconds, the distance the jam moved in the viscometer tank was recorded. The viscosity was recorded at the very front of the reading area. The test results are shown in Table 1.

[0132] Adhesion test method: A BROOKFIELD CT3 texture analyzer was used. The distance was set to 10 mm, the forward speed was 1 mm / s, the backward speed was 1 mm / s, and the contact load was 1 g. The adhesion index indicates the work done to overcome the attraction between the food surface and the contact surface. The test results are shown in Table 1.

[0133] Table 1. Results of viscosity and adhesiveness tests for the jam

[0134] Example 1 4.0 -433.6 Example 2 4.4 -326.2 Example 3 3.6 -385.7 Comparative Example 1 5.8 -390.5 Comparative Example 2 1.5 -172.3 Comparative Example 3 6.7 -236.2 Comparative Example 4 5.3 -286.3 Comparative Example 5 5.7 -241.2 Comparative Example 6 4.0 -433.6 Comparative Example 7 4.0 -433.6

[0135] Experimental Example 2

[0136] This experimental example conducts sensory evaluation and jam clarity tests on the jam yogurt prepared in the above examples and comparative examples. The test methods are as follows:

[0137] The sensory performance of freshly filled products was observed to verify the impact resistance of different jam formulas. The results are as follows: Figures 2-11 As shown.

[0138] In addition, the clarity of the jam in the product after reaching the fermentation endpoint was observed to verify the interaction between different filling methods and different jam formulas. The results are shown in Table 2. In Table 2, the jam clarity rate percentage is the percentage of jam-filled yogurt products with clear jam in the same batch out of the total number of jam-filled yogurt products in that batch. The criteria for judging jam clarity are as follows: Figure 12 As shown, the jam is clearly visible from the side wall.

[0139] Table 2. Percentage of Jam Clarity in Jam Yogurt

[0140] Example 1 100％ Example 2 100％ Example 3 96.3％ Comparative Example 1 67.4％ Comparative Example 2 13.5％ Comparative Example 3 43.3％ Comparative Example 4 48.1％ Comparative Example 5 40.6％ Comparative Example 6 73.3％ Comparative Example 7 78.9％

[0141] From Table 1 and Figures 2-11 As can be seen from the appearance, the jam and milk base in the products prepared in Examples 1-3 show a clear boundary, and the jam remains intact without dispersion. In contrast, in Comparative Examples 1 and 3-5, due to the low viscosity and high fluidity of the jam, it was observed from the bottom of the container that the jam was dispersed by the milk base to be fermented. Although the jam in Comparative Example 2 had a high viscosity, its adhesion was insufficient, allowing the milk base to easily seep into the gaps between the jam and the container wall, causing the jam to move as a whole and making it impossible to observe a clear view of the jam from the side of the container. Comparative Example 6 showed the highest degree of dispersion of the jam from the bottom of the container. This indicates that the upper milk base, using a center-filling method, had the strongest impact on the jam due to its low viscosity, resulting in most of the jam being dispersed and exhibiting the worst appearance. Furthermore, the large-scale mixing of the jam and milk base poses a risk of affecting subsequent fermentation.

[0142] From Table 2 and Figures 2-11 It can be seen that after fermentation and ripening, 120 barrels of jam prepared in the examples and comparative examples were randomly sampled to observe the clarity of the jam. Statistical analysis showed that the jam clarity rate of Examples 1-3 was above 95%, indicating good overall performance. However, the clarity rate of the jam in Comparative Examples 1-7 was below 80%, with Comparative Example 2 showing the lowest clarity rate. This indicates that simply increasing the viscosity of the jam cannot prevent the wetting and penetration of low-viscosity liquids such as milk base. In actual production, although the jam is not easily dispersed, its overall adhesion to the barrel wall is insufficient, making it more easily washed away or moved during fermentation, resulting in unclear jam in the finished product. The clarity rate of the jam in Comparative Examples 6 and 7 was lower than that in Example 1, indicating that the milk base filling method also greatly affects the dispersion and washing away of the jam.

[0143] The above demonstrates that jams with suitable viscosity and adhesion have good impact resistance and adhesion to the cylinder wall. Combined with the diagonal pouring method mentioned in this invention, the product can be guaranteed to present the best appearance.

Claims

1. A method for preparing layered jam yogurt, comprising the following steps: After mixing milk and auxiliary materials, homogenize and sterilize them, and then inoculate them with fermentation bacteria to obtain the milk base to be fermented. layered fruit jam yogurt, wherein the fruit jam is fermented, the layered fruit jam yogurt is packaged after fermentation, and the layered fruit jam yogurt is finally cold-ripened after packaging, and The method for layering fermented milk base and jam is as follows: first, pour jam into one corner of the container, then pour a portion of fermented milk base into the container from the opposite corner, and finally pour the remaining fermented milk base into the container from the center. The raw materials of the jam include: 10-20 wt% sugars, 30-50 wt% fruit pieces, 2-7 wt% stabilizer, 0.1-1.5 wt% calcium salts, 0.01-0.5 wt% acidity regulator, and the balance being water; wherein the stabilizer is a combination of pectin and hydroxypropyl distarch phosphate, with the amount of pectin being 0.2-2 wt% and the amount of hydroxypropyl distarch phosphate being 2-6 wt% based on the total mass of the raw materials; the calcium salt is a combination of calcium lactate and milk mineral salt, with the amount of calcium lactate being 0.1-0.5 wt% and the amount of milk mineral salt being 0.05-0.5 wt% based on the total mass of the raw materials.

2. The method for preparing layered jam yogurt according to claim 1, wherein, The material temperature is 70-75℃, and the material processing time is 20-35 minutes.

3. The method for preparing layered jam yogurt according to claim 1, wherein, The excipients include sugars, stabilizers, and emulsifiers.

4. The method for preparing layered jam yogurt according to claim 1, wherein, The homogenization temperature is 60-65℃, the secondary pressure is 20-40 bar, and the total pressure is 180-200 bar.

5. The method for preparing layered jam yogurt according to claim 1, wherein, The sterilization temperature is 95±2℃ and the time is 300s.

6. The method for preparing layered jam yogurt according to claim 1, wherein, The temperature of the fermented milk base during filling is 43±1℃.

7. The method for preparing layered jam yogurt according to claim 1, wherein, The fermentation temperature is 45±2℃, and the fermentation endpoint is when the acidity reaches 70-90°T.

8. The method for preparing layered jam yogurt according to claim 1, wherein, The post-cold ripening temperature is 4-6℃.

9. The method for preparing layered jam yogurt according to claim 1, wherein, The sugars include at least one of white sugar, fructose syrup, crystalline fructose, polydextrose, and resistant dextrin.

10. The method for preparing layered jam yogurt according to claim 1, wherein, The sugar is white granulated sugar, and the mass percentage of white granulated sugar is 12-18 wt%.

11. The method for preparing layered jam yogurt according to claim 1, wherein, The fruit pieces include at least one of the following: strawberry, blueberry, raspberry, cranberry, pineapple, mango, lemon, passion fruit, apricot, orange, tangerine, cherry, kiwi, banana, dragon fruit, apple, pear, hawthorn, grape, durian, pomegranate, lychee, mulberry, star fruit, loquat, pomelo, plum, peach, yellow peach, and guava.

12. The method for preparing layered jam yogurt according to claim 1, wherein, The size of the fruit pieces is 3mm×3mm×3mm-10mm×10mm×10mm.

13. The method for preparing layered jam yogurt according to claim 1, wherein, The viscosity of the jam at 20°C was measured to be 3.5-4.5 cm using a BOSTWICK viscometer.

14. The method for preparing layered jam yogurt according to claim 1, wherein, The jam's adhesiveness was measured to be -300 mJ to -500 mJ when tested on a BROOKFIELD texture analyzer in Normal mode.

15. Layered jam yogurt prepared by the preparation method according to any one of claims 1-14.

Images