Astringency removal method of aronia melanocarpa, aronia melanocarpa fruit pulp, ice cream and preparation method thereof

Abstract

This invention provides a method for removing astringency from black chokeberry, comprising the following steps: subjecting fresh black chokeberry fruit to a stepped heating treatment to obtain astringency-removed black chokeberry fruit; wherein the stepped heating treatment involves at least two heating increases, and the final temperature of the stepped heating treatment is 50℃~60℃. Compared with the prior art, this invention uses segmented low-temperature variable-temperature drying, rather than constant-temperature drying, avoiding the problems of moisture retention in the constant-temperature drying chamber, severe fruit moisture loss, and severe deformation; and partially evaporates the internal moisture of the fresh fruit, preventing rapid shrinkage and deformation, while accelerating the ripening process of the fresh fruit, effectively reducing the tannin content in the fruit, reducing astringency, and to a certain extent solving the bitterness of black chokeberry fruit, providing more possibilities for further processing of black chokeberry fruit.

Description

Technical Field

[0001] This invention belongs to the field of food technology, and particularly relates to a method for removing astringency from black chokeberry, black chokeberry pulp, ice cream, and their preparation methods. Background Technology

[0002] Frozen drinks are popular summer snacks for cooling down, but most of the products currently on the market are traditional and lack health benefits, offering a limited experience and causing consumer fatigue with ice cream products. Therefore, it is essential to continue exploring innovative product concepts to break the deadlock in the ice cream industry.

[0003] Black chokeberry, also known as wild chokeberry or immortal berry, is a berry fruit with health benefits. Black chokeberry fruit and its extracts have special therapeutic effects on cardiovascular diseases such as heart disease and hypertension, and are also rich in antioxidants such as anthocyanins and flavonoids. However, due to the high tannin content in black chokeberry fruit, related products have an astringent taste, affecting the consumer's eating experience. Therefore, black chokeberry juice undergoes a de-astringency treatment to remove tannins and reduce astringency.

[0004] To reduce the astringency of black chokeberry, the following methods can be used: 1) Using food-grade pectinase: Adding an appropriate amount of pectinase can increase the juice yield of black chokeberry, thereby reducing astringency; 2) Using polyvinylpyrrolidone (PVP): Treating at 50℃ for 40 minutes with 1.75% PVP can effectively reduce astringency; 3) Using gelatin: Treating at 48℃ for 45 minutes with 1.5% gelatin can also achieve a good deastringency effect; 4) Using tanninase and yeast: Adding an appropriate amount of tanninase and yeast can reduce astringency to some extent. However, all of the above methods require the addition of additional substances, which will affect the overall system of ice cream. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a method for removing astringency from black chokeberry, black chokeberry pulp, ice cream and a method for preparing the same. The method for removing astringency does not require the addition of other additives, so that the ice cream with black chokeberry pulp has a moderately sweet and sour taste and also has antioxidant health benefits.

[0006] This invention provides a method for removing astringency from black chokeberry, comprising the following steps:

[0007] Fresh black chokeberry fruit was subjected to a stepped heating process to obtain de-astringent black chokeberry fruit.

[0008] The stepped heating process involves at least two heating cycles, and the final temperature of the stepped heating process is between 50°C and 60°C.

[0009] Preferably, the temperature increase in the stepped heating process is 10°C to 20°C each time, starting from the first heat preservation.

[0010] And / or, the total holding time for the stepped heating treatment is 1.5 to 8 hours, and the holding time gradually decreases.

[0011] Preferably, the stepped heating treatment includes a first heat preservation, a second heat preservation, and a third heat preservation;

[0012] The temperature of the first heat preservation is 30℃~40℃; the time of the first heat preservation is 1~2 hours;

[0013] The temperature for the second heat preservation is 40℃~50℃; the time for the second heat preservation is 0.5~1h;

[0014] The temperature for the third heat preservation is 50℃~60℃; the time for the third heat preservation is 0.3~0.5h.

[0015] The present invention also provides a black chokeberry pulp, which is obtained by grinding fresh black chokeberry fruit with water after processing it with the above-mentioned de-astringency method.

[0016] The present invention also provides a cold beverage product comprising the above-mentioned black chokeberry pulp.

[0017] The present invention also provides an ice cream, comprising:

[0018]

[0019] Add water to a total of 100 parts by weight.

[0020] Preferably, the protein raw material is selected from one or more of milk, milk powder, whey powder and coconut milk;

[0021] And / or, the sweetener comprises a solid sweetener and a syrup; the mass ratio of the solid sweetener to the syrup is (11-13):(4-6);

[0022] And / or, the stabilizer comprises stearic acid stabilizers and colloids; the mass ratio of the stearic acid stabilizers to the colloids is (0.1-0.2):(0.4-0.76).

[0023] Preferably, the solid sweetener is selected from one or more of white sugar, sucrose, glucose, sorbitol, xylitol, mannitol, maltitol and erythritol;

[0024] The syrup is selected from one or more of malt syrup, fructose syrup and corn syrup;

[0025] The stearic acid stabilizer is selected from monoglyceride stearate and / or diglyceride stearate;

[0026] The colloid is selected from xanthan gum, carrageenan and locust bean gum.

[0027] The present invention also provides a method for preparing the above-mentioned ice cream, comprising the following steps:

[0028] S1) Mix protein raw materials, sweeteners, black chokeberry pulp, β-cyclodextrin, stabilizers and water to obtain a liquid mixture;

[0029] S2) After homogenization, sterilization, aging and freezing of the liquid, ice cream is obtained.

[0030] Preferably, the mixing temperature in step S1) is 55℃~65℃; the mixing time is 15~20min;

[0031] The homogenization temperature in step S2) is 65℃~70℃; the homogenization is a two-stage homogenization; the pressure of the first-stage homogenization is 140~160 bar, and the pressure of the second-stage homogenization is 40~45 bar.

[0032] The aging temperature in step S2) is 0℃~6℃; the aging time is 4~6h;

[0033] The freezing outlet temperature in step S2) is -4℃ to -6℃.

[0034] This invention provides a method for removing astringency from black chokeberry, comprising the following steps: subjecting fresh black chokeberry fruit to a stepped heating treatment to obtain astringency-removed black chokeberry fruit; wherein the stepped heating treatment involves at least two heating increases, and the final temperature of the stepped heating treatment is 50℃~60℃. Compared with the prior art, this invention uses segmented low-temperature variable-temperature drying, rather than constant-temperature drying, avoiding the problems of moisture retention in the constant-temperature drying chamber, severe fruit moisture loss, and severe deformation; and partially evaporates the internal moisture of the fresh fruit, preventing rapid shrinkage and deformation, while accelerating the ripening process of the fresh fruit, effectively reducing the tannin content in the fruit, reducing astringency, and to a certain extent solving the bitterness of black chokeberry fruit, providing more possibilities for further processing of black chokeberry fruit.

[0035] Furthermore, this invention provides an ice cream comprising: 45-50 parts by weight of protein raw materials; 15-19 parts by weight of sweetener; 2-4 parts by weight of black chokeberry pulp; 1-1.5 parts by weight of β-cyclodextrin; 0.5-0.96 parts by weight of stabilizer; and water to bring the total to 100 parts by weight. Compared with existing technologies, this invention is the first to propose adding β-cyclodextrin to the ice cream system, replacing the commonly used maltodextrin. This provides the solids required for ice cream, eliminates off-flavors, improves the stability of flavorings and colorings, enhances emulsification and moisture resistance, and improves the texture of the food. Simultaneously, the adsorption effect of β-cyclodextrin can adsorb around tannins to a certain extent, creating an encapsulation phenomenon, which can reduce the astringency of black chokeberry to some extent. It also gives the ice cream antioxidant activity, effectively scavenging free radicals in the body and achieving a beauty and antioxidant effect. Attached Figure Description

[0036] Figure 1 The graph shows the tannin content results in ice cream obtained from Examples 1-5 and Comparative Examples 1-5 of the present invention.

[0037] Figure 2 The graph shows the DPPH free radical scavenging rate results of ice cream obtained in Examples 1-5 and Comparative Examples 1-5 of the present invention. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] This invention provides a method for removing astringency from black chokeberry, comprising the following steps: subjecting fresh black chokeberry fruit to a stepped heating treatment to obtain black chokeberry fruit after astringency removal; wherein the stepped heating treatment involves at least two heating cycles and the final temperature of the stepped heating treatment is 50℃~60℃.

[0040] In this invention, there are no special restrictions on the source of any raw materials; they can be commercially available.

[0041] In this invention, the fresh fruit of the black chokeberry is preferably pre-treated; the pre-treatment is preferably washing and removing the stems.

[0042] The pretreated fresh black chokeberry fruit is subjected to a stepped heating treatment; the stepped heating treatment involves at least two heating increases; the stepped heating treatment includes multiple heat preservation cycles; the number of heat preservation cycles is at least two; the temperature increase for each heat preservation cycle, starting from the first heat preservation cycle, is preferably 10℃ to 20℃, more preferably 10℃ to 15℃, and even more preferably 10℃; the total heat preservation time for the stepped heating treatment is preferably 1.5 to 8 hours, more preferably 2 to 5 hours, even more preferably 3 to 4 hours, and most preferably 3.3 to 3.5 hours; the heat preservation time for each heat preservation cycle in the stepped heating treatment gradually decreases.

[0043] In one specific embodiment of the present invention, the stepped heating treatment is preferably carried out in a hot air drying oven.

[0044] In one specific embodiment of the present invention, the stepped heating treatment includes a first heat preservation, a second heat preservation, and a third heat preservation; the temperature of the first heat preservation is preferably 30℃~40℃; the duration of the first heat preservation is preferably 1~2h, more preferably 1.5~2h; the temperature of the second heat preservation is preferably 40℃~50℃; the duration of the second heat preservation is preferably 0.5~1h, more preferably 0.8~1h; the temperature of the third heat preservation is preferably 50℃~60℃; the duration of the third heat preservation is preferably 0.3~0.5h, more preferably 0.3h. In some embodiments of the present invention, the temperature of the first heat preservation is specifically 30℃, 35℃, or 40℃; in some embodiments of the present invention, the temperature of the second heat preservation is specifically 40℃, 45℃, or 50℃; in some embodiments of the present invention, the temperature of the third heat preservation is specifically 50℃, 55℃, or 60℃.

[0045] In a specific embodiment of the present invention, during the process of multiple heat treatments and heat preservation in a stepped heating process, it is preferable to also perform a buffering treatment at room temperature; the buffering treatment time is preferably 1 to 20 minutes, more preferably 5 to 15 minutes, even more preferably 8 to 12 minutes, and most preferably 10 minutes; by performing buffering treatment at room temperature, the problem of severe moisture loss and deformation of the fruit can be further avoided, and the appearance of the fruit can be maintained.

[0046] In one specific embodiment of the present invention, the caching process is preferably performed before the final heat preservation and heating.

[0047] In one specific embodiment of the present invention, the caching process is preferably performed after the second heat preservation is completed.

[0048] This invention utilizes segmented low-temperature variable-temperature drying, rather than constant-temperature drying, to avoid the problems of moisture retention and severe fruit dehydration and deformation that occur in constant-temperature drying chambers. Furthermore, it partially evaporates the internal moisture of the fresh fruit, preventing rapid shrinkage and deformation, while simultaneously accelerating the ripening process. This effectively reduces the tannin content in the fruit, lessening its astringency and thus mitigating the bitterness of black chokeberry to some extent, providing more possibilities for its subsequent deep processing.

[0049] The present invention also provides a black chokeberry pulp, which is obtained by grinding fresh black chokeberry fruit with water after processing it with the above-mentioned de-astringency method.

[0050] In one specific embodiment of the present invention, the amount of water used is preferably the same as the amount of water lost by the fresh fruit of the black chokeberry during the de-astringency treatment.

[0051] In one specific embodiment of the present invention, the grinding time is preferably 20 to 40 seconds.

[0052] The present invention also provides a cold beverage product comprising the above-mentioned black chokeberry pulp.

[0053] In one specific embodiment of the present invention, the cold beverage product may be one or more of ice cream, popsicles, ice pops, and beverages.

[0054] In one specific embodiment of the present invention, the mass of the black chokeberry pulp is preferably 2% to 4% of the mass of the cold drink product, more preferably 3%.

[0055] In one specific embodiment of the present invention, the frozen beverage product preferably further includes β-cyclodextrin; the mass of the β-cyclodextrin is preferably 1% to 1.5% of the frozen beverage product.

[0056] The present invention also provides an ice cream comprising 45-50 parts by weight of protein raw material; 15-19 parts by weight of sweetener; 2-4 parts by weight of black chokeberry pulp; 1-1.5 parts by weight of β-cyclodextrin; 0.5-0.96 parts by weight of stabilizer; and water to make up to 100 parts by weight.

[0057] In one specific embodiment of the present invention, the protein raw material can be any protein raw material known to those skilled in the art, and there are no special restrictions. In the present invention, it is preferably one or more of milk, milk powder, whey powder and coconut milk.

[0058] In one specific embodiment of this invention, the protein raw material is coconut milk. Using natural coconut milk instead of raw milk makes the ice cream more nutritious and healthier.

[0059] In a specific embodiment of the present invention, the sweetener content in ice cream is preferably 16-19 parts by weight, more preferably 17-19 parts by weight, and even more preferably 18 parts by weight; the sweetener preferably includes a solid sweetener and a syrup; the mass ratio of the solid sweetener to the syrup is preferably (11-13):(4-6), more preferably (12-13):(4-6), even more preferably (12-13):(5-6), and most preferably 12:6; the solid sweetener can be any solid sweetener known to those skilled in the art, and there are no special limitations. In the present invention, it is preferably one or more of white sugar, sucrose, glucose, sorbitol, xylitol, mannitol, maltitol, and erythritol; the syrup is preferably one or more of malt syrup, fructose syrup, and corn syrup.

[0060] In one specific embodiment of the present invention, the content of the black chokeberry pulp in ice cream can be 2 parts by weight, 3 parts by weight, 4 parts by weight, or any two of the above values.

[0061] In one specific embodiment of the present invention, the content of β-cyclodextrin in ice cream is preferably 1 to 1.2 parts by weight.

[0062] In a specific embodiment of the present invention, the content of the stabilizer in ice cream is preferably 0.6-0.9 parts by weight, more preferably 0.65-0.85 parts by weight, even more preferably 0.7-0.8 parts by weight, and most preferably 0.7-0.75 parts by weight; the stabilizer preferably includes stearic acid stabilizers and colloids; the mass ratio of the stearic acid stabilizer to the colloid is preferably (0.1-0.2):(0.4-0.76), more preferably (0.1-0.2):(0.4-0.7), and even more preferably (0.1-0.76). 2): (0.4-0.6), more preferably (0.1-0.2): (0.5-0.6), and most preferably 0.15:0.56; the stearic acid stabilizer is preferably monoglyceride stearate and / or diglyceride stearate; the colloid is preferably xanthan gum, carrageenan and locust bean gum; the mass ratio of xanthan gum, carrageenan and locust bean gum is preferably 1: (0.1-0.3): (0.1-0.3), more preferably 1: (0.15-0.25): (0.15-0.25), and even more preferably 1:0.2:0.2.

[0063] In a specific embodiment of the present invention, the ice cream preferably further includes an edible flavoring; the edible flavoring can be any edible flavoring known to those skilled in the art, and there are no special limitations. In the embodiment provided by the present invention, a compound berry flavoring is used as an example for illustration; the content of the edible flavoring in the ice cream is preferably 0.05 to 0.5 parts by weight, more preferably 0.05 to 0.3 parts by weight, even more preferably 0.05 to 0.2 parts by weight, and most preferably 0.1 parts by weight.

[0064] This invention applies variable temperature drying technology to remove astringency from fresh black chokeberry fruit, solving the problem of unpleasant astringency inherent in black chokeberry. At the same time, β-cyclodextrin is added to further reduce the sourness and astringency of black chokeberry, resulting in an ice cream with a better flavor, a moderately sweet and sour taste, and antioxidant health benefits.

[0065] The present invention also provides a method for preparing ice cream, comprising the following steps: S1) mixing protein raw materials, sweeteners, black chokeberry pulp, β-cyclodextrin, stabilizers and water to obtain a liquid mixture; S2) homogenizing, sterilizing, aging and freezing the liquid mixture to obtain ice cream.

[0066] In this invention, there are no special restrictions on the source of any raw materials; commercially available materials are acceptable. The types and amounts of the protein raw materials, sweeteners, black chokeberry pulp, β-cyclodextrin, stabilizers, and water are the same as those described above and will not be repeated here.

[0067] Protein raw materials, sweeteners, black chokeberry pulp, β-cyclodextrin, stabilizers and water are mixed to obtain a liquid mixture; the mixing temperature is preferably 55℃~65℃, more preferably 60℃; the mixing time is 15~20min.

[0068] The feed liquid is homogenized; the homogenization temperature is preferably 65℃~70℃; the homogenization is preferably a two-stage homogenization; the pressure of the first-stage homogenization is preferably 140~160 bar, more preferably 145~155 bar, and even more preferably 150 bar, and the pressure of the second-stage homogenization is preferably 40~45 bar.

[0069] The homogenized liquid is sterilized; the sterilization method is any method known to those skilled in the art and there are no special limitations. The sterilization temperature in this invention is preferably 80℃~90℃, more preferably 85℃; the sterilization time is preferably 20~40s, more preferably 25~35s, and even more preferably 30s.

[0070] The sterilized liquid is aged; the aging temperature is preferably 0℃~6℃; the aging time is preferably 4~6h.

[0071] The aged liquid material is frozen; the outlet temperature of the freezing process is preferably -4℃ to -6℃, more preferably -5℃; the expansion rate of the liquid material during freezing is preferably 1% to 100%, more preferably 30% to 60%, and even more preferably 40% to 50%.

[0072] According to the present invention, after freezing, it is preferable to further freeze to obtain ice cream; the freezing temperature is preferably -20℃ to -40℃.

[0073] This invention is the first to propose adding β-cyclodextrin to an ice cream system, replacing the commonly used maltodextrin. This provides the solids needed for ice cream, eliminates off-flavors, improves the stability of flavorings and colorings, enhances emulsification and moisture resistance, and improves the taste of the food. At the same time, the adsorption effect of β-cyclodextrin can adsorb around tannins to a certain extent, creating an encapsulation phenomenon. This can reduce the astringency of black chokeberry to some extent, and also give the ice cream antioxidant activity, effectively scavenging free radicals in the body and achieving beauty and antioxidant effects.

[0074] To further illustrate the present invention, the following describes in detail, with reference to embodiments, a method for removing astringency from black chokeberry, black chokeberry pulp, ice cream, and their preparation methods.

[0075] All reagents used in the following examples are commercially available; the maltose content in the malt syrup used in the examples and comparative examples is 40%-50%; the viscosity of xanthan gum is 1300-1600 cp (referring to xanthan gum, a food additive produced by Xanthomonas aureus as the producing bacterium, starch as the main raw material, through specific biological fermentation, purification, drying, and pulverization, with a shear property value ≥6.5, and passing the identification test of GB1886.41); the carrageenan is type K (Kappa).

[0076] Comparative Example 1

[0077] 1.1 Pretreatment of Black Sorbus nigra: Take fresh Black Sorbus nigra fruit, wash and remove the stems.

[0078] 1.2 Grinding Black Sorrel Fruit: Take 3% by weight of pretreated fresh Black Sorrel Fruit and grind the processed fresh fruit from step 1.1 into a pulp using a food processor, and set aside.

[0079] 1.3 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0080] 1.4 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0081] 1.5 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0082] 1.6 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0083] 1.7 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0084] 1.8 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0085] 1.9 Packaging: After freezing, it is poured into cups and shaped.

[0086] 1.10 Freezing: The contents are placed in a cold storage and frozen solid.

[0087] Comparative Example 2

[0088] 2.1 Pretreatment of Black-fruited Sorbus nigra: Take fresh Black-fruited Sorbus nigra, wash and remove the stems.

[0089] 2.2 Grinding of Black Sorrel Fruit: Take 3% by weight of pretreated fresh Black Sorrel Fruit and grind the processed fresh fruit from step 2.1 into a pulp using a food processor, and set aside.

[0090] 2.3 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0091] 2.4 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0092] 2.5 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0093] 2.6 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0094] 2.7 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0095] 2.8 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0096] 2.9 Packaging: After freezing, it is poured into cups and shaped.

[0097] 2.10 Freezing: The contents are placed in a cold storage and frozen solid.

[0098] Comparative Example 3

[0099] 3.1 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0100] 3.2 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0101] 3.3 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0102] 3.4 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0103] 3.5 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0104] 3.6 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0105] 3.7 Packaging: After freezing, it is poured into cups and shaped.

[0106] 3.8 Freezing: The contents are frozen solid upon entering the cold storage.

[0107] Comparative Example 4

[0108] 4.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0109] 4.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M), and dry it once at a constant temperature of 60℃ for 3.3 hours; finally weigh it (m).

[0110] 4.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 4.2 and mix it with Mm of water. Grind it in a food processor to obtain black chokeberry pulp for later use.

[0111] 4.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0112] 4.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0113] 4.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0114] 4.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0115] 4.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0116] 4.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0117] 4.10 Packaging: After freezing, it is poured into cups and shaped.

[0118] 4.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0119] Comparative Example 5

[0120] 5.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0121] 5.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M), and dry it twice. The first drying temperature is 50℃ for 2 hours; the second drying temperature is 60℃ for 1.3 hours; finally weigh it (m).

[0122] 5.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 5.2 and mix it with Mm of water, then grind it in a food processor to obtain black chokeberry pulp, and set aside.

[0123] 5.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0124] 5.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0125] 5.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0126] 5.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0127] 5.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0128] 5.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0129] 5.10 Packaging: After freezing, it is poured into cups and shaped.

[0130] 5.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0131] Example 1

[0132] 1.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0133] 1.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fruit (M) and dry it three times. The first drying temperature is 35℃ for 2 hours; the second drying temperature is 45℃ for 1 hour; and the third drying temperature is 55℃ for 0.3 hours. The fruit is taken out of the drying oven between the second and third drying times and weighed m.

[0134] 1.3 Black chokeberry pulp: Take the black chokeberry that has undergone the de-astringency treatment in 1.2 and mix it with Mm of water. Grind it in a food processor to obtain black chokeberry pulp, and set it aside.

[0135] 1.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 2% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0136] 1.5 Circulation and stirring: After the liquid has been brought to a constant volume, stir it in a water bath at 55-65℃ for 15-20 minutes.

[0137] 1.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0138] 1.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0139] 1.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0140] 1.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0141] 1.10 Packaging: After freezing, it is poured into cups and shaped.

[0142] 1.11 Freezing: The contents of a cold storage facility are frozen solid.

[0143] Example 2

[0144] 2.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0145] 2.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M) and dry it three times. The first drying temperature is 35℃ for 2 hours; the second drying temperature is 45℃ for 1 hour; and the third drying temperature is 55℃ for 0.3 hours. Finally, weigh it (m).

[0146] 2.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 2.2 and mix it with Mm of water, then grind it in a food processor to obtain black chokeberry pulp, and set aside.

[0147] 2.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0148] 2.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0149] 2.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0150] 2.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0151] 2.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0152] 2.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0153] 2.10 Packaging: After freezing, it is poured into cups and shaped.

[0154] 2.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0155] Example 3

[0156] 3.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0157] 3.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M) and dry it three times. The first drying temperature is 35℃ for 2 hours; the second drying temperature is 45℃ for 1 hour; and the third drying temperature is 55℃ for 0.3 hours. Finally, weigh m.

[0158] 3.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 3.2 and mix it with Mm of water. Grind it in a food processor to obtain black chokeberry pulp for later use.

[0159] 3.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 4% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0160] 3.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0161] 3.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0162] 3.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0163] 3.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0164] 3.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0165] 3.10 Packaging: After freezing, it is poured into cups and shaped.

[0166] 3.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0167] Example 4

[0168] 4.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh M;

[0169] 4.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M), and dry it three times. The first drying temperature is 30℃ for 2 hours; the second drying temperature is 40℃ for 1 hour; the third drying temperature is 50℃ for 0.3 hours; and the fourth drying temperature is 55℃ for 0.2 hours. Finally, weigh it (m).

[0170] 4.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 4.2 and mix it with Mm of water. Grind it in a food processor to obtain black chokeberry pulp for later use.

[0171] 4.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0172] 4.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0173] 4.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0174] 4.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0175] 4.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0176] 4.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0177] 4.10 Packaging: After freezing, it is poured into cups and shaped.

[0178] 4.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0179] Example 5

[0180] 5.1 Pretreatment of black chokeberry: Take fresh black chokeberry fruit, wash and remove the stems, and weigh it (M).

[0181] 5.2 De-astringency treatment of black chokeberry: Take an appropriate amount of pretreated black chokeberry fresh fruit (M) and dry it three times. The first drying temperature is 40℃ for 2 hours; the second drying temperature is 50℃ for 1 hour; the third drying temperature is 60℃ for 0.3 hours; the fourth drying temperature is 55℃ for 0.2 hours; and finally weigh it (m).

[0182] 5.3 Grinding of black chokeberry: Take the black chokeberry after the de-astringency treatment in 5.2 and mix it with Mm of water, then grind it in a food processor to obtain black chokeberry pulp, and set aside.

[0183] 5.4 Mixing: Mix 50% coconut milk, 12% white sugar, 6% malt syrup, 3% black chokeberry pulp, 1% β-cyclodextrin, 1.5‰ monoglyceride stearate, 0.4% xanthan gum, 0.8‰ carrageenan, 0.8‰ locust bean gum, and 1‰ compound berry flavoring according to the specified ratio, stir well, and then add water to make up to the final volume.

[0184] 5.5 Circulation and stirring: After the liquid has been brought to a constant volume, it is stirred in a 60℃ water bath for 20 minutes.

[0185] 5.6 Homogenization: Set the homogenization temperature to 70℃, the first-stage pressure to 150 bar, the second-stage pressure to 45 bar, and homogenize at a uniform speed.

[0186] 5.7 Sterilization: Heat the homogenized liquid to 85℃ for 30 seconds for sterilization.

[0187] 5.8 Aging: After sterilization, the liquid is cooled to below 6°C and aged for 6 hours.

[0188] 5.9 Freezing: After aging, the liquid material enters the freezer with an expansion rate of 50% and the outlet temperature is adjusted to -5℃.

[0189] 5.10 Packaging: After freezing, it is poured into cups and shaped.

[0190] 5.11 Freezing: The contents are placed in a cold storage and frozen solid.

[0191] Sensory evaluations were conducted on the ice creams obtained in Examples 1-5 and Comparative Examples 1-5. Evaluations were performed across four dimensions: texture, palatability, appearance, and overall liking, with a maximum score of 10. Ten individuals were selected for the evaluation. Higher scores indicated greater liking.

[0192] The comparison revealed that all embodiments were superior to the comparative embodiments in terms of taste; embodiments 2 and 5 showed better palatability; and embodiment 2 showed better overall likability. In summary, embodiment 2 was considered the optimal embodiment.

[0193] Table 1 Sensory evaluation results

[0194] taste Palatability Appearance Overall Preference Example 1 8.81±0.43 8.54±0.32 8.64±0.2 8.36±0.32 Example 2 9.1±0.3 9.22±0.27 8.68±0.29 9.13±0.3 Example 3 8.73±0.35 8.61±0.39 8.63±0.33 8.78±0.18 Example 4 8.83±0.22 8.93±0.31 9.59±0.18 8.98±0.17 Example 5 9.03±0.15 9.11±0.19 8.48±0.4 8.8±0.36 Comparative Example 1 8.38±0.36 8.69±0.41 8.66±0.34 8.47±0.21 Comparative Example 2 8.43±0.32 8.75±0.27 8.66±0.2 8.56±0.2 Comparative Example 3 8.21±0.43 8.46±0.36 8.53±0.29 8.08±0.35 Comparative Example 4 8.63±0.31 8.65±0.37 8.59±0.21 8.88±0.21 Comparative Example 5 8.59±0.54 8.61±0.29 8.54±0.24 8.74±0.18

[0195] The soluble tannin content was determined using a UV-Vis spectrophotometer according to the standard NYT1600-2008 "Determination of Tannin Content in Fruits, Vegetables and Their Products by Spectrophotometry". Gallic acid was used as a standard to construct a standard curve and establish a regression equation.

[0196] Take 2g of melted ice cream, add 20mL of deionized water, mix well, centrifuge at 8000r / min for 5min, take the supernatant, and make up to 100mL.

[0197] Take 1.0 mL each of gallic acid standard solutions of 0.00 mg / L, 10.0 mg / L, 20.0 mg / L, 30.0 mg / L, 40.0 mg / L, and 50.0 mg / L, and add 5.0 mL of distilled water, 1.0 mL of sodium tungstate-sodium molybdate mixed solution (preparation method as per NYT1600-2008 Determination of Tannin Content in Fruits, Vegetables and Their Products by Spectrophotometry), and 3.0 mL of 75 g / L sodium carbonate solution, respectively. Mix well. The concentrations of the gallic acid standard solutions are 0.0 mg / L, 1.0 mg / L, 2.0 mg / L, 3.0 mg / L, 4.0 mg / L, and 5.0 mg / L, respectively. Develop the color and let stand for 2 hours. Use 0.0 mg / L as the blank for the standard curve. The absorbance of the standard solution was measured at a wavelength of 765 nm. A standard curve was plotted with gallic acid concentration on the ordinate and absorbance values ​​on the abscissa, ranging from 0.1375 to 0.1332. R0 2 =0.9997.

[0198] Take 1.0 mL of the sample extract and add 5.0 mL of distilled water, 1.0 mL of sodium tungstate-sodium molybdate mixed solution (as above), and 3.0 mL of 75 g / L sodium carbonate solution. Mix well, develop color, and let stand for 2 hours, using 0.0 mg / L as a blank for the standard curve. Measure the absorbance of the sample solution at 765 nm wavelength. Calculate the tannin concentration of the sample solution, expressed as gallic acid, based on the standard curve.

[0199] The tannin (calculated as gallic acid) content in the sample was calculated according to Formula I, and the tannin content results are shown in the figure below. Figure 1 As shown.

[0200] Tannin content = C × 10 × A / m (Equation I)

[0201] In Formula I: C is the concentration of gallic acid in the sample test solution (mg / L); A is the sample dilution factor; m is the sample mass (g); and 10 is the final volume of the sample test solution (mL).

[0202] The bitterness of black chokeberry mainly comes from its tannin content. The bleaching effect is characterized by measuring the soluble tannin content. Higher tannin content indicates a more astringent fruit and a less desirable taste. Figure 1 The tannin content results of the comparative examples and embodiments show that, with the same amount of black chokeberry pulp added, the tannin content of Examples 2, 4, and 5 is significantly lower than that of Comparative Example 1, indicating that variable-temperature heating has a de-astringency effect. With the same amount of black chokeberry pulp added, the tannin content of Comparative Example 2, which added β-cyclodextrin, is slightly lower than that of Comparative Example 1, indicating that the addition of β-cyclodextrin contributes to the reduction of tannin content to some extent. Furthermore, comparing Examples 2, 4, and 5, i.e., different variable-temperature drying de-astringency parameters with the same amount of black chokeberry pulp added, reveals slight differences in tannin content among the three examples. Moreover, comparing Comparative Examples 4 and 5 with Example 5, i.e., different processes with the same amount of black chokeberry pulp added, reveals that although the tannin content of the three examples differs slightly, the differences are not significant. However, considering the overall energy consumption, the most suitable variable-temperature drying de-astringency parameter is that of Example 2.

[0203] Take 1.0 mL of the ice cream melt from the comparative and example samples at different mass concentrations into test tubes, add 1.0 mL of 4 mmol / L DPPH ethanol solution, mix well, and let stand in the dark for 30 min. Use 2.0 mL of ethanol as a blank and a mixture of 1.0 mL of 4 mmol / L DPPH ethanol solution and 1.0 mL of ethanol as a control. Measure the absorbance at 517 nm. Calculate the DPPH free radical scavenging rate according to Formula II. The results are as follows. Figure 2 As shown.

[0204] DPPH removal rate (%) = (1-A1 / A0)×100 (Equation II)

[0205] In the formula, A1 is the absorbance of the sample solution; A0 is the absorbance of the control solution.

[0206] from Figure 2 The results show that all experimental groups with added black chokeberry fruit exhibited good antioxidant capacity. Comparing Examples 2, 4, 5, and Comparative Example 1 with the same amount of black chokeberry pulp, it was found that the variable-temperature drying de-astringency treatment did not affect the antioxidant active ingredients in the final product. Furthermore, comparing Comparative Examples 4 and 5 with Example 5—that is, different processes with the same amount of black chokeberry pulp—revealed the differences between constant temperature, two-stage variable temperature, and three-stage variable temperature. While Comparative Examples 4 and 5 showed better de-astringency effects than the examples, the advantages were not significant, and they required higher energy consumption. Similarly, it was found that the variable-temperature drying de-astringency treatment did not affect the antioxidant active ingredients in the final product.

[0207] Based on the above experimental results and a comprehensive comparison of deastringency, sensory evaluation, and antioxidant capacity, Example 2 is considered the optimal example.

[0208] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for removing astringency from black chokeberry, characterized in that, Includes the following steps: Fresh black chokeberry fruit was subjected to a stepped heating process to obtain de-astringent black chokeberry fruit. The stepped heating process involves at least two heating cycles, and the final temperature of the stepped heating process is between 50°C and 60°C.

2. The de-abrasion method according to claim 1, characterized in that, The stepped heating process begins with a temperature increase of 10℃ to 20℃ each time, starting from the first heat preservation. And / or, the total holding time for the stepped heating treatment is 1.5 to 8 hours, and the holding time gradually decreases.

3. The de-abrasion method according to claim 1, characterized in that, The stepped heating process includes a first heat preservation, a second heat preservation, and a third heat preservation. The temperature of the first heat preservation is 30℃~40℃; the time of the first heat preservation is 1~2 hours; The temperature for the second heat preservation is 40℃~50℃; the time for the second heat preservation is 0.5~1h; The temperature for the third heat preservation is 50℃~60℃; the time for the third heat preservation is 0.3~0.5h.

4. A kind of black chokeberry pulp, characterized in that, It is obtained by processing fresh black chokeberry fruit through the deastringency method described in any one of claims 1 to 3, followed by grinding with water.

5. A cold beverage product, characterized in that, Includes the black chokeberry pulp as described in claim 4.

6. An ice cream, characterized in that, include: Add water to a total of 100 parts by weight.

7. The ice cream according to claim 6, characterized in that, The protein raw material is selected from one or more of milk, milk powder, whey powder and coconut milk; And / or, the sweetener comprises a solid sweetener and a syrup; the mass ratio of the solid sweetener to the syrup is (11-13):(4-6); And / or, the stabilizer comprises stearic acid stabilizers and colloids; the mass ratio of the stearic acid stabilizers to the colloids is (0.1-0.2):(0.4-0.76).

8. The ice cream according to claim 7, characterized in that, The solid sweetener is selected from one or more of the following: white sugar, sucrose, glucose, sorbitol, xylitol, mannitol, maltitol, and erythritol. The syrup is selected from one or more of malt syrup, fructose syrup and corn syrup; The stearic acid stabilizer is selected from monoglyceride stearate and / or diglyceride stearate; The colloid is selected from xanthan gum, carrageenan and locust bean gum.

9. A method for preparing ice cream according to claim 6, characterized in that, Includes the following steps: S1) Mix protein raw materials, sweeteners, black chokeberry pulp, β-cyclodextrin, stabilizers and water to obtain a liquid mixture; S2) After homogenization, sterilization, aging and freezing of the liquid, ice cream is obtained.

10. The preparation method according to claim 9, characterized in that, The mixing temperature in step S1) is 55℃~65℃; the mixing time is 15~20min; The homogenization temperature in step S2) is 65℃~70℃; the homogenization is a two-stage homogenization; the pressure of the first-stage homogenization is 140~160 bar, and the pressure of the second-stage homogenization is 40~45 bar. The aging temperature in step S2) is 0℃~6℃; the aging time is 4~6h; The freezing outlet temperature in step S2) is -4℃ to -6℃.

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