Low-acidity jam and preparation method thereof

Abstract

The invention discloses low-acidity jam and a preparation method thereof, and belongs to the technical field of jam, the low-acidity jam comprises the following raw materials by weight: 10-14% of a wild licorice stem freeze-dried extract, 4-7% of a plumule-removed lotus seed fermentation product, 2-4% of cucumber juice, 2-7% of a phyllanthus emblica pericarp heat-treated product, 2-4% of cellulase, 2-3% of hesperidin, 0.3-1% of sodium carbonate, and the balance of apples. The wild liquorice stem freeze-dried extract is obtained by blanching, salting, cooking and cooling stems of wild liquorice; the plumule-removed lotus seed fermentation product is obtained by plumule-removed lotus seeds, grinding the plumule-removed lotus seeds, mixing the ground plumule-removed lotus seeds with carrageenan and water, adding lactobacillus bulgaricus and performing constant-temperature culture; the phyllanthus emblica fruit heat treatment substance is obtained by frying, cooling and crushing the peel of phyllanthus emblica fruit. The pH stability of the jam can be effectively improved and the color stability can be improved by adding the freeze-dried wild liquorice stem extract, and the color stability of the jam can be effectively improved and the pH stability can be improved by adding the pericarp heat-treated substance of the phyllanthus emblica.

Description

Technical Field

[0001] The invention relates to the technical field of jam, and in particular to a low-acid jam and a preparation method thereof. Background Art

[0002] Jam is made from fruits, sugar and other main raw materials through processes such as pretreatment, cooking, beating, mixing and concentration.

[0003] For example, CN107581552A discloses a method for preparing apple jam, wherein the method comprises: cutting apples and carrots into pieces and beating them to obtain jam N; mixing jam N, sugar, citric acid, salt, pectin, color preservative and sweetener to obtain jam M; boiling and concentrating jam M, and then canning and sealing it and sterilizing it to obtain apple jam. This method solves the problem that ordinary jams easily lose the flavor of the fruits in the raw materials and that jams are not easy to store for a long time.

[0004] However, in order to cover up the sour taste of the jam, the sugar content in the raw materials accounts for 5% to 7%, which poses health risks such as obesity, high blood sugar and tooth decay. At the same time, the stability of the jam also needs to be further improved, and the storage time at room temperature is relatively short.

[0005] Based on this, the present invention designs a low-acid jam and a preparation method thereof to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a low-acid jam and a preparation method thereof.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A low-acid jam comprises the following raw materials in percentage by weight: 10-14% of a freeze-dried extract of wild liquorice stems, 4-7% of fermented cored lotus seeds, 2-4% of cucumber juice, 2-7% of a heat-treated peel of emblica fruit, 2-4% of cellulase, 2-3% of hesperidin, 0.3-1% of sodium carbonate, and the remainder of apples;

[0009] The wild licorice stem freeze-dried extract is obtained by blanching, salt soaking, steaming and cooling the wild licorice stem;

[0010] The cored lotus seed fermented product is obtained by removing the core of the lotus seeds, grinding them, mixing them with carrageenan and water, and adding Lactobacillus bulgaricus for constant temperature culture;

[0011] The heat-treated emblica fruit material is obtained by frying, cooling and crushing the emblica fruit peel.

[0012] Furthermore, the blanching step is: after washing the stems of wild licorice, cut them into small sections of 1 to 1.2 cm, freeze-dried at -40°C, and then blanched in hot water at 65 to 75°C for 25 to 30 seconds.

[0013] Furthermore, the salt soaking step is: adding the stems of wild licorice to a 10-15% sodium chloride solution and salt soaking for 20-30 minutes.

[0014] Furthermore, the cooking step is: the stems of wild licorice are placed in 1 volume of water, and then placed under a pressure of 0.3-0.5 MPa and cooked for 5-8 minutes.

[0015] Furthermore, the constant temperature culture condition is: constant temperature culture at 39-40°C for 2-3 days.

[0016] Furthermore, the frying step is: heat the olive oil to 110-115° C., put the peel of the emblica fruit into the hot olive oil and fry it until crispy, and the peel of the emblica fruit does not turn black.

[0017] Furthermore, the crushing step is: crushing the peel of the emblica fruit into 30-40 mesh particles.

[0018] In order to better achieve the purpose of the present invention, the present invention also provides a method for preparing low-acid jam, comprising the following steps:

[0019] 1. Preparation of Freeze-dried Extract of Licorice Stem

[0020] The stems of wild licorice are washed, cut into small pieces of 1 to 1.2 cm, freeze-dried at -40°C, firstly put into hot water at 65 to 75°C for 25 to 30 seconds, then put into 10 to 15% sodium chloride solution for salt soaking for 20 to 30 minutes, then taken out and put into 1 times volume of water, then placed under a pressure of 0.3 to 0.5 MPa for 5 to 8 minutes, cooled and filtered to obtain the freeze-dried extract of wild licorice stems;

[0021] 2. Preparation of cored lotus seed fermentation

[0022] The lotus seeds are cored, cleaned, dried at 45-60° C., ground and sieved to 200-300 meshes, then mixed evenly with 0.5-1 times the volume of carrageenan and 1-2 times the volume of water, and activated Lactobacillus bulgaricus is added, and the mixture is placed at 39-40° C. for constant temperature culture for 2-3 days, sterilized, and filtered to obtain the cored lotus seed fermentation product;

[0023] 3. Preparation of heat-treated emblica fruit

[0024] Heat the olive oil to 110-115°C, clean the emblica fruit and peel it, fry the emblica fruit peel in hot olive oil until it is crispy, and the emblica fruit peel is not black, then remove the emblica fruit peel and cool it for 3-5 minutes, and crush it into 30-40 mesh particles;

[0025] 4. Prepare low-acid jam

[0026] The apples are washed, peeled and cored, sodium carbonate is added, and the mixture is stirred at 45-50° C. for 10-20 minutes. The mixture is then pulped and filtered, and cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica fruit are added, and the jam is obtained after heating and concentration.

[0027] Furthermore, the activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed at a ratio of 1:10:0.1-0.3, sterilized and cooled to 39-40°C, then inoculated with Lactobacillus bulgaricus at a rate of 1-3%, and cultured until coagulation occurs.

[0028] In order to better achieve the purpose of the present invention, the present invention also provides a low-acid jam prepared according to the preparation method.

[0029] Compared with the prior art, the present invention has the following beneficial effects: the present invention is prepared by using a freeze-dried extract of wild licorice stems, fermented lotus seeds without cores, cucumber juice, heat-treated peel of emblica fruit, cellulase, hesperidin, sodium carbonate and apple, and does not use granulated sugar, thereby reducing the health risks caused by high granulated sugar content; the acidity of the jam is low (pH is close to neutral), which is more suitable for people with oral sensitivity or excessive gastric acid; by adding the freeze-dried extract of wild licorice stems, it not only has a certain sweetness, reduces acidity, but also can effectively improve the pH stability of the jam, and is also conducive to improving the color (brightness) stability, by adding the heat-treated peel of emblica fruit, the color (brightness) stability of the jam can be effectively improved, and at the same time, it can be conducive to improving the pH stability, the reason may be that the peel of emblica fruit loses water after frying, has a certain adsorption effect, is conducive to locking color and fixing color, and at the same time, due to its good adsorption effect, can improve the pH stability to a certain extent. The jam of the present invention has a good storage effect at 10°C, and the storage time exceeds 100h. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described 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.

[0031] Embodiment 1: In some embodiments, a method for preparing low-acid jam comprises the following steps:

[0032] 1. Prepare the raw materials: 10% freeze-dried extract of wild licorice stems, 7% fermented lotus seeds without cores, 2% cucumber juice, 7% heat-treated peel of emblica fruit, 2% cellulase, 3% hesperidin, 0.3% sodium carbonate, and the balance is apples;

[0033] 2. Preparation of freeze-dried extract of wild licorice stem: After washing the stem of wild licorice, cut it into small pieces of 1 cm, freeze-dried it at -40°C, first put it in hot water at 75°C for 25 seconds, then add it to a 15% sodium chloride solution and soak it for 20 minutes, then take it out and put it in 1 times the volume of water, then cook it at a pressure of 0.5MPa for 5 minutes, cool it, filter it, and obtain the freeze-dried extract of wild licorice stem;

[0034] 3. Preparation of cored lotus seed fermentation product: cored lotus seeds, cleaned them, dried them at 45°C, ground them and sieved them through 300 mesh, then mixed them evenly with 0.5 times the volume of carrageenan and 2 times the volume of water, and then added with activated Lactobacillus bulgaricus, and cultured them at a constant temperature of 39°C for 3 days, sterilized them, and filtered them to obtain the cored lotus seed fermentation product;

[0035] The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.1, sterilized and cooled to 40°C, and then inoculated with Lactobacillus bulgaricus in a 1% inoculation amount and cultured until coagulation;

[0036] 4. Preparation of heat-treated emblica fruit: heat olive oil to 110°C, clean and peel the emblica fruit, fry the emblica fruit peel in hot olive oil until crispy, at which time the emblica fruit peel is not black, then remove the emblica fruit peel and cool for 5 minutes, and crush into 30 mesh particles;

[0037] 5. Preparation of low-acid jam: Wash the apples, peel and core them, add sodium carbonate, stir and mix at 45°C for 20 minutes, then pulp and filter, add cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica fruit, heat and concentrate to obtain jam.

[0038] The jam (100 g) just prepared was taken and the pH was tested to be 6.4 and the color (brightness) (tested by Konica Minolta CR-10 Plus) was 69.5; then the 100 g jam was divided into two portions, each of 50 g.

[0039] One of the jams was stored at 25°C for 80 h, and the pH was 5.6 and the color (brightness) was 56.2;

[0040] Another portion of jam was stored at 10°C for 100 h, and the pH was 6.0 and the color (brightness) was 62.8.

[0041] Embodiment 2: In some embodiments, a method for preparing low-acid jam comprises the following steps:

[0042] 1. Prepare the raw materials: 14% freeze-dried extract of wild licorice stems, 4% fermented lotus seeds without cores, 4% cucumber juice, 2% heat-treated peel of emblica fruit, 4% cellulase, 2% hesperidin, 1% sodium carbonate, and the balance is apples;

[0043] 2. Preparation of freeze-dried extract of wild licorice stem: After washing the stem of wild licorice, cut it into small pieces of 1.2 cm, freeze-dried at -40°C, first put it in 65°C hot water for 30 seconds, then add it to 10% sodium chloride solution and soak it for 30 minutes, then take it out and put it in 1 times the volume of water, then cook it at 0.3MPa pressure for 8 minutes, cool it, filter it, and obtain the freeze-dried extract of wild licorice stem;

[0044] 3. Preparation of cored lotus seed fermentation product: cored lotus seeds, cleaned them, dried them at 60°C, ground them and sieved them through 200 mesh, then mixed them evenly with 1 volume of carrageenan and 1 volume of water, added activated Lactobacillus bulgaricus, cultured them at a constant temperature of 40°C for 2 days, sterilized them, filtered them and obtained the cored lotus seed fermentation product;

[0045] The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.3, sterilized and cooled to 39°C, and then inoculated with Lactobacillus bulgaricus at a 3% inoculum amount and cultured until coagulation;

[0046] 4. Preparation of heat-treated emblica fruit: heat olive oil to 115°C, clean and peel the emblica fruit, fry the emblica fruit peel in hot olive oil until crispy, at which time the emblica fruit peel is not black, remove the emblica fruit peel, cool for 3 minutes, and crush into 40 mesh particles;

[0047] 5. Preparation of low-acid jam: Wash the apples, peel and core them, add sodium carbonate, stir and mix at 50°C for 10 minutes, then pulp and filter, add cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica oleracea, heat and concentrate to obtain jam.

[0048] Take the jam (100 g) just prepared, and check the pH value to be 6.7 and the color (brightness) to be 70.4; then divide the 100 g jam into two portions, each of 50 g.

[0049] One of the jams was stored at 25°C for 80 h, and the pH was 5.9 and the color (brightness) was 57.3;

[0050] Another portion of jam was stored at 10°C for 100 h, and the pH was 6.2 and the color (brightness) was 64.2.

[0051] Embodiment 3: In some embodiments, a method for preparing low-acid jam comprises the following steps:

[0052] 1. Prepare the raw materials: 12% freeze-dried extract of wild licorice stems, 5.7% fermented lotus seeds without cores, 3.2% cucumber juice, 4.6% heat-treated peel of emblica fruit, 2.8% cellulase, 2.4% hesperidin, 0.5% sodium carbonate, and the balance is apples;

[0053] 2. Preparation of freeze-dried extract of wild licorice stem: After washing the stem of wild licorice, cut it into small pieces of 1.1 cm, freeze-dried at -40°C, first put it in 68°C hot water for 28 seconds, then add it to 12% sodium chloride solution and soak it for 25 minutes, then take it out and put it in 1 times the volume of water, then cook it at 0.4MPa pressure for 7 minutes, cool it, filter it, and obtain the freeze-dried extract of wild licorice stem;

[0054] 3. Preparation of cored lotus seed fermentation product: cored lotus seeds, cleaned them, dried them at 50°C, ground them and sieved them through 250 mesh, then mixed them evenly with 0.7 times the volume of carrageenan and 1.6 times the volume of water, and then added with activated Lactobacillus bulgaricus, and cultured them at a constant temperature of 39.6°C for 2.5 days, and sterilized and filtered them to obtain the cored lotus seed fermentation product;

[0055] The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.2, sterilized and cooled to 39.6°C, and then inoculated with Lactobacillus bulgaricus in a 2.2% inoculum amount and cultured until curdled milk;

[0056] 4. Preparation of heat-treated emblica fruit: heat olive oil to 112°C, clean and peel the emblica fruit, fry the emblica fruit peel in hot olive oil until crispy, at which time the emblica fruit peel is not black, remove the emblica fruit peel, cool for 4 minutes, and crush into 30 mesh particles;

[0057] 5. Preparation of low-acid jam: Wash the apples, peel and core them, add sodium carbonate, stir and mix at 48°C for 13 minutes, then pulp and filter, add cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica oleracea, heat and concentrate to obtain jam.

[0058] Take the jam (100 g) just prepared, and check the pH value to be 6.9 and the color (brightness) to be 69.3; then divide the 100 g jam into two portions, each of 50 g.

[0059] One of the jams was stored at 25°C for 80 h, and the pH was 5.4 and the color (brightness) was 53.0;

[0060] Another portion of jam was stored at 10°C for 100 h, and the pH was 6.4 and the color (brightness) was 61.3.

[0061] Comparative Example 1: In some embodiments, a method for preparing low-acid jam comprises the following steps:

[0062] 1. Prepare the raw materials: 5.7% fermented lotus seeds without core, 3.2% cucumber juice, 4.6% heat-treated peel of emblica fruit, 2.8% cellulase, 2.4% hesperidin, 0.5% sodium carbonate, and the balance is apples;

[0063] 2. Preparation of cored lotus seed fermentation product: cored lotus seeds, cleaned them, dried them at 50°C, ground them and sieved them through 250 mesh, then mixed them evenly with 0.7 times volume of carrageenan and 1.6 times volume of water, then added activated Lactobacillus bulgaricus, placed them at 39.6°C for constant temperature culture for 2.5 days, sterilized them, filtered them and obtained the cored lotus seed fermentation product;

[0064] The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.2, sterilized and cooled to 39.6°C, and then inoculated with Lactobacillus bulgaricus in a 2.2% inoculum amount and cultured until curdled milk;

[0065] 4. Preparation of heat-treated emblica fruit: heat olive oil to 112°C, clean and peel the emblica fruit, fry the emblica fruit peel in hot olive oil until crispy, at which time the emblica fruit peel is not black, remove the emblica fruit peel, cool for 4 minutes, and crush into 30 mesh particles;

[0066] 5. Preparation of low-acid jam: Wash the apples, peel and core them, add sodium carbonate, stir and mix at 48°C for 13 minutes, then pulp and filter, add cellulase, hesperidin, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica fruit, heat and concentrate to obtain jam.

[0067] Take the jam (100 g) just prepared, and check the pH value to be 6.9 and the color (brightness) to be 64.4; then divide the 100 g jam into two portions, each of 50 g.

[0068] One of the jams was stored at 25°C for 80 h, and the pH was 3.6 and the color (brightness) was 41.7;

[0069] Another jam was stored at 10°C for 100 h, and the pH was 4.5 and the color (brightness) was 43.9.

[0070] Comparative Example 2: In some embodiments, a method for preparing low-acid jam comprises the following steps:

[0071] 1. Prepare the raw materials: 12% freeze-dried extract of wild licorice stems, 5.7% fermented lotus seeds without cores, 3.2% cucumber juice, 4.6% heat-treated peel of emblica fruit, 2.8% cellulase, 2.4% hesperidin, 0.5% sodium carbonate, and the balance is apples;

[0072] 2. Preparation of freeze-dried extract of wild licorice stem: After washing the stem of wild licorice, cut it into small pieces of 1.1 cm, freeze-dried at -40°C, first put it in 68°C hot water for 28 seconds, then add it to 12% sodium chloride solution and soak it for 25 minutes, then take it out and put it in 1 times the volume of water, then cook it at 0.4MPa pressure for 7 minutes, cool it, filter it, and obtain the freeze-dried extract of wild licorice stem;

[0073] 3. Preparation of cored lotus seed fermentation product: cored lotus seeds, cleaned them, dried them at 50°C, ground them and sieved them through 250 mesh, then mixed them evenly with 0.7 times the volume of carrageenan and 1.6 times the volume of water, and then added with activated Lactobacillus bulgaricus, and cultured them at a constant temperature of 39.6°C for 2.5 days, and sterilized and filtered them to obtain the cored lotus seed fermentation product;

[0074] The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.2, sterilized and cooled to 39.6°C, and then inoculated with Lactobacillus bulgaricus in a 2.2% inoculum amount and cultured until curdled milk;

[0075] 4. Preparation of heat-treated emblica fruit: heat olive oil to 40°C, clean and peel the emblica fruit, put the emblica fruit peel into hot olive oil for 1 minute, then remove the emblica fruit peel and cool for 4 minutes, and crush into 30 mesh particles;

[0076] 5. Preparation of low-acid jam: Wash the apples, peel and core them, add sodium carbonate, stir and mix at 48°C for 13 minutes, then pulp and filter, add cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica oleracea, heat and concentrate to obtain jam.

[0077] Take the jam (100 g) just prepared, and check the pH value to be 6.9 and the color (brightness) to be 67.1; then divide the 100 g jam into two portions, each of 50 g.

[0078] One of the jams was stored at 25°C for 80 h, and the pH was 4.0 and the color (brightness) was 33.1;

[0079] Another portion of jam was stored at 10°C for 100 h, and the pH was 5.2 and the color (brightness) was 36.8.

[0080] The present invention is prepared by using a freeze-dried extract of wild liquorice stems, fermented lotus seeds without cores, cucumber juice, heat-treated peel of emblica fruit, cellulase, hesperidin, sodium carbonate and apples, and does not use granulated sugar, thereby reducing the health risks caused by high granulated sugar content; the acidity of the jam is low (pH is close to neutral), which is more suitable for people with oral sensitivity or hyperacidity; by adding the freeze-dried extract of wild liquorice stems, it not only has a certain sweetness, reduces acidity, but also can effectively improve the pH stability of the jam, and is also conducive to improving the color (brightness) stability, by adding the heat-treated peel of emblica fruit, the color (brightness) stability of the jam can be effectively improved, and it can be conducive to improving the pH stability, the reason may be that the peel of emblica fruit loses water after frying, has a certain adsorption effect, is conducive to locking color and fixing color, and at the same time, due to its good adsorption effect, can improve the pH stability to a certain extent. The jam of the present invention has a good storage effect at 10°C, and the storage time exceeds 100h.

[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-acid jam, characterized in that: The invention comprises the following raw materials in percentage by weight: 10-14% of freeze-dried extract of wild liquorice stem, 4-7% of fermented lotus seeds without core, 2-4% of cucumber juice, 2-7% of heat-treated peel of emblica fruit, 2-4% of cellulase, 2-3% of hesperidin, 0.3-1% of sodium carbonate, and the balance of apples; The wild licorice stem freeze-dried extract is obtained by blanching, salt soaking, steaming and cooling the wild licorice stem; The cored lotus seed fermented product is obtained by removing the core of the lotus seeds, grinding them, mixing them with carrageenan and water, and adding Lactobacillus bulgaricus for constant temperature culture; The heat-treated emblica fruit material is obtained by frying, cooling and crushing the emblica fruit peel.

2. The low-acid jam according to claim 1, characterized in that The blanching steps are as follows: the stems of wild licorice are washed, cut into small sections of 1 to 1.2 cm, freeze-dried at -40°C, and then blanched in hot water at 65 to 75°C for 25 to 30 seconds.

3. The low-acid jam according to claim 2, characterized in that The salt soaking step is as follows: adding the stems of wild licorice into a 10-15% sodium chloride solution and salt soaking for 20-30 minutes.

4. The low-acid jam according to claim 3, characterized in that The cooking steps are as follows: the stems of wild licorice are put into 1 times the volume of water, and then are placed under a pressure of 0.3-0.5 MPa and cooked for 5-8 minutes.

5. The low-acid jam according to claim 4, characterized in that The constant temperature culture conditions are: constant temperature culture at 39-40°C for 2-3 days.

6. The low-acid jam according to claim 5, characterized in that The frying steps are as follows: heat the olive oil to 110-115° C., put the peel of the emblica fruit into the hot olive oil and fry until crispy. At this time, the peel of the emblica fruit has not turned black.

7. The low-acid jam according to claim 6, characterized in that The crushing step is as follows: crush the peel of the emblica fruit into 30-40 mesh particles.

8. A method for preparing low-acid jam according to claim 7, characterized in that: The following steps are involved:

1. Preparation of Freeze-dried Extract of Licorice Stem The stems of wild licorice are washed, cut into small pieces of 1 to 1.2 cm, freeze-dried at -40°C, firstly put into hot water at 65 to 75°C for 25 to 30 seconds, then put into 10 to 15% sodium chloride solution for salt soaking for 20 to 30 minutes, then taken out and put into 1 times volume of water, then placed under a pressure of 0.3 to 0.5 MPa for 5 to 8 minutes, cooled and filtered to obtain the freeze-dried extract of wild licorice stems; 2. Preparation of cored lotus seed fermentation The lotus seeds are cored, cleaned, dried at 45-60° C., ground and sieved to 200-300 meshes, then mixed evenly with 0.5-1 times the volume of carrageenan and 1-2 times the volume of water, and activated Lactobacillus bulgaricus is added, and the mixture is placed at 39-40° C. for constant temperature culture for 2-3 days, sterilized, and filtered to obtain the cored lotus seed fermentation product; 3. Preparation of heat-treated emblica fruit Heat the olive oil to 110-115°C, clean the emblica fruit and peel it, fry the emblica fruit peel in hot olive oil until it is crispy, and the emblica fruit peel is not black, then remove the emblica fruit peel and cool it for 3-5 minutes, and crush it into 30-40 mesh particles; 4. Prepare low-acid jam The apples are washed, peeled and cored, sodium carbonate is added, and the mixture is stirred at 45-50° C. for 10-20 minutes. The mixture is then pulped and filtered, and cellulase, hesperidin, freeze-dried extract of wild licorice stems, fermented cored lotus seeds, cucumber juice and heat-treated peel of emblica fruit are added, and the jam is obtained after heating and concentration.

9. The method for preparing low-acid jam according to claim 8, characterized in that: The activation method of Lactobacillus bulgaricus is as follows: skimmed milk powder, water and sodium ascorbate are mixed in a ratio of 1:10:0.1-0.3, sterilized and cooled to 39-40°C, then inoculated with Lactobacillus bulgaricus in a ratio of 1-3%, and cultured until coagulation.

10. A low-acid jam prepared according to the preparation method according to claim 9.