Preparation method of cold-extracted freeze-dried coffee powder with fruit flavor

Abstract

The invention relates to the technical field of food processing, in particular to a preparation method of fruit-flavored cold-extracted freeze-dried coffee powder, which comprises the following specific steps: S1, fruit raw material pretreatment: S1.1, raw material selection: selecting fresh fruits which are free of plant diseases and insect pests and moderate in maturity; s1.2, cleaning and impurity removal: putting the selected fruits into clear water, scrubbing to remove dust and pesticide residues on the surfaces, flushing the fruits with flowing water, and removing inedible parts on the surfaces of the fruits at the same time; through fine fruit raw material pretreatment and biological enzymolysis technologies, aromatic substances and nutritional ingredients in fruits are successfully released and perfectly fused with the cold extraction coffee liquid, so that the original mellow taste and fragrance of coffee are reserved, the coffee is endowed with unique fruit flavor, and the taste of the coffee is improved. In addition, by controlling the conditions and the mixing proportion of the enzymolysis reaction, the flavor and the taste of the coffee powder can be accurately adjusted, and the individual requirements of different consumers are met.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a method for preparing cold-brewed freeze-dried coffee powder with fruit flavor. Background Art

[0002] In today's rapidly developing coffee market, consumers' demand for coffee quality, taste and flavor diversity is growing. Traditional coffee products mainly rely on factors such as the origin, variety and roasting process of coffee beans to shape their unique flavor, but this flavor is often limited to the aroma of the coffee beans themselves and the complex compounds produced by chemical reactions during the roasting process. Although these traditional coffee products already have a large consumer group, with the improvement of consumers' health awareness and the diversification of taste preferences, the market demand for innovative, healthy and unique coffee products is becoming more urgent.

[0003] In recent years, the coffee market has begun to explore cross-border integration with various ingredients to create a more novel and unique flavor experience. Among them, the combination of fruit and coffee has become a hot trend. Fruit, with its natural sweetness, acidity and rich fruity aroma, brings a new flavor level and taste experience to coffee. However, directly mixing fruit with coffee is often difficult to fully release the flavor substances in the fruit, and it is easy to affect the original flavor balance of the coffee.

[0004] In the traditional method of preparing cold-brewed freeze-dried coffee powder with fruit flavor, the macromolecules in the fruit raw materials are often difficult to be effectively released by conventional methods in the coffee preparation process, resulting in insufficient flavor fusion, affecting the taste and flavor complexity of the final product. Secondly, in the traditional coffee making process, the addition of fruit flavor mostly relies on direct mixing of essences or fruit particles. This method not only makes it difficult to maintain the fresh flavor and nutritional components of the fruit, but may also introduce unnecessary additives, affecting the health attributes of the product.

[0005] In order to solve the above problems, it is necessary to optimize the existing methods, use bio-enzymatic hydrolysis technology to process fruit raw materials, and combine it with cold brew coffee technology to prepare coffee products that have rich fruit flavor and retain the original characteristics of coffee, bringing consumers a new coffee experience and meeting the market's urgent demand for high-quality, healthy, and uniquely flavored coffee products. Summary of the invention

[0006] Technical issues solved

[0007] In view of the above-mentioned shortcomings of the prior art, the present invention provides a method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, which decomposes macromolecular substances in fruits through enzymatic hydrolysis to release more natural flavor substances and nutrients, and then combines the fruit components after enzymatic hydrolysis with cold-brewed coffee liquid, and uses cold-brew technology to retain the original flavor and nutrients of the coffee. Finally, the mixed liquid is made into cold-brewed freeze-dried coffee powder that is easy to store and carry through freeze-drying technology. This preparation method not only significantly improves the flavor specificity and taste richness of coffee, but also retains the natural nutrients and active substances of fruits, making coffee products healthier and more nutritious. At the same time, the convenience of cold-brewed freeze-dried coffee powder also meets the personalized needs of consumers for coffee products under modern fast-paced lifestyles.

[0008] Technical Solution

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0010] A method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, the specific steps of the method comprising:

[0011] S1. Pretreatment of fruit raw materials:

[0012] S1.1. Raw material selection: Select fresh fruits that are free of pests and diseases and are moderately mature;

[0013] S1.2, Washing and removing impurities: Put the selected fruits into clean water, scrub to remove dust and pesticide residues on the surface, and rinse with running water, while removing the inedible parts on the surface of the fruits;

[0014] S1.3 Crushing: Use a food-grade crusher or blender to crush the cleaned fruits. For fruits with a harder texture and stronger flavor, use a more powerful crusher for preliminary crushing. For fruits with a softer texture and more delicate flavor, use stirring or squeezing. Filter the crushed fruits to remove impurities and solid particles.

[0015] S2. Biological enzymatic treatment:

[0016] S2.1. Preparation of enzymatic hydrolysate: Select biological enzymes according to the type and characteristics of the fruit, and prepare the enzymatic hydrolysate in a certain proportion, while adjusting the pH value of the enzymatic hydrolysate to the optimal action range of the enzyme;

[0017] S2.2, mixed enzymolysis: evenly mix the filtered fruit juice with the prepared enzymolysis solution so that the enzyme can fully contact and act on the macromolecular substances in the fruit;

[0018] S2.3, enzymatic hydrolysis reaction: placing the mixed solution in a constant temperature water bath or enzymatic hydrolysis reactor, and controlling the reaction temperature and time;

[0019] S2.4. Termination of enzymatic hydrolysis: When the enzymatic hydrolysis reaction reaches a predetermined degree, the enzymatic hydrolysis reaction is terminated by heating.

[0020] S3. Cold brew coffee preparation:

[0021] S3.1. Coffee bean grinding: Select high-quality coffee beans and use a grinder to grind them into fine powder suitable for cold brewing;

[0022] S3.2, cold extraction: mix the ground coffee powder and cold water in a certain proportion, and place the mixture in a low temperature environment and let it soak for cold extraction;

[0023] S3.3, Filtration: After cold brewing is completed, use filter paper or filter mesh to filter the coffee liquid to remove coffee grounds and impurities.

[0024] S4, Mixing and Drying:

[0025] S4.1, mixing: mixing the enzymatically hydrolyzed fruit ingredients and the cold brewed coffee liquid evenly in a certain proportion;

[0026] S4.2, stirring and blending: Use a blender to fully stir the mixture to fully blend the fruit ingredients with the coffee liquid;

[0027] S4.3. Freeze drying: Pour the mixed liquid into the tray of the freeze dryer for pre-freezing. After the mixed liquid is completely frozen, start the vacuum pump and heating system of the freeze dryer to perform freeze drying in a low-temperature vacuum environment.

[0028] S5. Packaging and storage:

[0029] S5.1. Packaging: Select packaging materials with good sealing properties, moisture-proof and oxidation-proof properties to package the freeze-dried coffee powder;

[0030] S5.2, Labels and instructions: Affix product labels and instructions to the packaging, indicating the product name, ingredients, production date, shelf life and storage conditions;

[0031] S5.3. Storage and transportation: Store the packaged coffee powder in a cool, dry and ventilated place, avoid direct sunlight and high temperature environment, and maintain the integrity and stability of the packaging during transportation.

[0032] Furthermore, in step S2.1, the biological enzyme is pectinase, the enzyme concentration is controlled at 0.1%-0.5% (w / v), and the pH value of the enzymatic solution is adjusted to 4.5-5.0.

[0033] Furthermore, in step S2.2, the crushed fruit pulp and the enzymatic hydrolysate are evenly mixed in a ratio of 1:1 to 1:2.

[0034] Furthermore, in step S2.3, the mixed solution is placed in a constant temperature water bath or an enzymolysis reactor, and the enzymolysis temperature is controlled to be 40° C.-60° C., and the enzymolysis time is 2-4 hours.

[0035] Furthermore, in step S2.4, when the enzymatic hydrolysis reaches a predetermined degree, the enzymatic hydrolysis reaction is terminated by heating to 80-85° C. and maintaining for 5 minutes.

[0036] Furthermore, the ground coffee powder in step S3.2 is mixed with cold water in a ratio of 1:8 to 1:12, the water temperature is controlled at 4°C, the mixture is placed in a sealed container, and allowed to stand and soak in a refrigerator for 12-24 hours for cold extraction.

[0037] Furthermore, in step S4.1, the enzymatically hydrolyzed fruit components and the cold brewed coffee liquid are evenly mixed in a ratio of 1:5 to 1:10.

[0038] Furthermore, in step S4.2, a stirrer is used to stir at a speed of 300 rpm for 10 minutes, and the temperature is maintained at 20-25° C. during the stirring process to avoid loss of flavor substances due to high temperature.

[0039] Furthermore, in step 4.3, the mixed liquid is poured into the tray of the freeze dryer, the thickness is controlled between 1-2 cm, the temperature is controlled at -40°C for pre-freezing treatment until the mixed liquid is completely frozen, the vacuum pump and heating system of the freeze dryer are started, and the freeze drying treatment is carried out under the conditions of vacuum degree less than 20Pa and heating plate temperature controlled at 40-60°C, and the drying time is set to 12-24 hours.

[0040] Beneficial Effects

[0041] Compared with the known public technology, the technical solution provided by the present invention has the following advantages:

[0042] Beneficial effects:

[0043] 1. The present invention successfully releases the aromatic substances and nutrients in the fruit through fine fruit raw material pretreatment and biological enzymatic hydrolysis technology, and perfectly integrates them with the cold-brewed coffee liquid, which not only retains the original mellow taste and aroma of the coffee, but also gives the coffee a unique fruit flavor, making the flavor level of the coffee more rich and diverse. In addition, by controlling the conditions and mixing ratio of the enzymatic hydrolysis reaction, the flavor and taste of the coffee powder can be accurately adjusted to meet the personalized needs of different consumer groups.

[0044] 2. The present invention uses biological enzymatic hydrolysis technology, which not only helps to release the nutrients in the fruit, but also retains the active substances produced in the enzymatic hydrolysis process. At the same time, the cold extraction process avoids the nutritional loss that may be caused by high-temperature baking, and completely retains the beneficial ingredients in the coffee. Therefore, the cold-extracted freeze-dried coffee powder prepared by the present invention not only has a unique flavor, but is also rich in various nutrients and has a higher nutritional value, satisfying the pursuit of healthy diet by modern consumers. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the present invention is described clearly and completely. 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.

[0046] The present invention will be further described below in conjunction with the embodiments.

[0047] A method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, characterized in that the specific steps of the method include:

[0048] S1. Pretreatment of fruit raw materials:

[0049] S1.1. Raw material selection: Select fresh fruits that are free of pests and diseases and are moderately mature;

[0050] S1.2, Washing and removing impurities: Put the selected fruits into clean water, scrub to remove dust and pesticide residues on the surface, and rinse with running water, while removing the inedible parts on the surface of the fruits;

[0051] S1.3 Crushing: Use a food-grade crusher or blender to crush the cleaned fruits. For fruits with a harder texture and stronger flavor, use a more powerful crusher for preliminary crushing. For fruits with a softer texture and more delicate flavor, use stirring or squeezing. Filter the crushed fruits to remove impurities and solid particles.

[0052] S2. Biological enzymatic hydrolysis treatment:

[0053] S2.1. Preparation of enzymatic hydrolysate: Select biological enzymes according to the type and characteristics of the fruit, and prepare the enzymatic hydrolysate in a certain proportion, while adjusting the pH value of the enzymatic hydrolysate to the optimal action range of the enzyme;

[0054] S2.2, mixed enzymolysis: evenly mix the filtered fruit juice with the prepared enzymolysis solution so that the enzyme can fully contact and act on the macromolecular substances in the fruit;

[0055] S2.3, enzymatic hydrolysis reaction: placing the mixed solution in a constant temperature water bath or enzymatic hydrolysis reactor, and controlling the reaction temperature and time;

[0056] S2.4. Termination of enzymatic hydrolysis: When the enzymatic hydrolysis reaction reaches a predetermined degree, the enzymatic hydrolysis reaction is terminated by heating.

[0057] S3. Cold brew coffee preparation:

[0058] S3.1. Coffee bean grinding: Select high-quality coffee beans and use a grinder to grind them into fine powder suitable for cold brewing;

[0059] S3.2, cold extraction: mix the ground coffee powder and cold water in a certain proportion, and place the mixture in a low temperature environment and let it soak for cold extraction;

[0060] S3.3, Filtration: After cold brewing is completed, use filter paper or filter mesh to filter the coffee liquid to remove coffee grounds and impurities.

[0061] S4, Mixing and Drying:

[0062] S4.1, mixing: mixing the enzymatically hydrolyzed fruit ingredients and the cold brewed coffee liquid evenly in a certain proportion;

[0063] S4.2, stirring and blending: Use a blender to fully stir the mixture to fully blend the fruit ingredients with the coffee liquid;

[0064] S4.3. Freeze drying: Pour the mixed liquid into the tray of the freeze dryer for pre-freezing. After the mixed liquid is completely frozen, start the vacuum pump and heating system of the freeze dryer to perform freeze drying in a low-temperature vacuum environment.

[0065] S5. Packaging and storage:

[0066] S5.1. Packaging: Select packaging materials with good sealing properties, moisture-proof and oxidation-proof properties to package the freeze-dried coffee powder;

[0067] S5.2, Labels and instructions: Affix product labels and instructions to the packaging, indicating the product name, ingredients, production date, shelf life and storage conditions;

[0068] S5.3. Storage and transportation: Store the packaged coffee powder in a cool, dry and ventilated place, avoid direct sunlight and high temperature environment, and maintain the integrity and stability of the packaging during transportation.

[0069] Embodiment 1

[0070] The present embodiment focuses on a method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, wherein fresh, pest-free and moderately mature fruits are selected, rubbed in clean water to remove surface dust and pesticide residues, rinsed with running water to remove inedible parts, crushed and filtered with a food-grade crusher, pectinase is selected, the enzyme concentration is controlled to be 0.1% (w / v), the pH value of the enzymatic solution is adjusted to 4.5, the crushed fruit slurry and the enzymatic solution are mixed in a ratio of 1:1, placed in a constant temperature water bath, the enzymatic solution temperature is controlled to be 40°C, the enzymatic solution time is 2 hours, after the enzymatic solution reaches a predetermined degree, it is heated to 80°C and maintained for 5 minutes to terminate the enzymatic solution reaction, high-quality coffee beans are selected, ground into fine powder suitable for cold brewing, the coffee powder is mixed with cold water in a ratio of 1:8, and the water temperature is controlled to be At 4°C, place in a sealed container and let stand in a refrigerator for 12 hours for cold extraction. After the cold extraction is completed, filter with filter paper, mix the enzymatically hydrolyzed fruit components with the cold-brewed coffee liquid in a ratio of 1:5, use a stirrer to stir at a rate of 300 rpm for 10 minutes, keep the temperature at 20°C, pour the mixed solution into a freeze dryer tray, control the thickness to 1 cm, pre-freeze at -40°C, start the vacuum pump and heating system of the freeze dryer, and perform freeze drying for 12 hours under the conditions of a vacuum degree lower than 20Pa and a heating plate temperature of 40°C. In this embodiment, the macromolecular substances in the fruit are partially decomposed, releasing a certain amount of flavor substances and nutrients. After mixing with the cold-brewed coffee liquid, the fruit flavor is lighter and the original flavor of the coffee is still obvious.

[0071] Embodiment 2

[0072] The present embodiment further optimizes the preparation method of cold-brewed freeze-dried coffee powder with fruit flavor, selects fresh, pest-free and moderately mature fruits, puts them into clean water and scrubs them to remove surface dust and pesticide residues, rinses them with running water to remove inedible parts, crushes them with a food-grade crusher and filters them, selects pectinase, controls the enzyme concentration to 0.2% (w / v), adjusts the pH value of the enzymolysis solution to 4.6, mixes the crushed fruit slurry with the enzymolysis solution in a 1:1 ratio, places them in a constant temperature water bath, controls the enzymolysis temperature to 48°C, and the enzymolysis time to 2.5 hours. After the enzymolysis reaches a predetermined degree, heats to 80°C and maintains for 5 minutes to terminate the enzymolysis reaction, selects high-quality coffee beans, grinds them into fine powder suitable for cold brewing, mixes the coffee powder with cold water, and The mixture is mixed at a ratio of 1:8, the water temperature is controlled at 4°C, placed in a sealed container and allowed to stand and soak in a refrigerator for 12 hours for cold extraction, filtered with filter paper after the cold extraction, the fruit components after enzymatic hydrolysis and the cold-brewed coffee liquid are evenly mixed at a ratio of 1:5, stirred at a rate of 300 rpm for 10 minutes using a stirrer, the temperature is maintained at 20°C, the mixed liquid is poured into a freeze dryer tray, the thickness is controlled at 1 cm, pre-frozen at -40°C, the vacuum pump and heating system of the freeze dryer are started, and freeze-dried for 12 hours under the conditions of a vacuum degree of less than 20Pa and a heating plate temperature of 40°C. In this embodiment, the degree of enzymatic hydrolysis of the fruit is deepened, the release of flavor substances is increased, and the fruit flavor is slightly stronger after mixing with the coffee liquid.

[0073] Embodiment 3

[0074] The present embodiment aims to prepare a cold-brewed freeze-dried coffee powder with a fruity flavor. Fresh, pest-free and moderately mature fruits are selected, rubbed in clean water to remove surface dust and pesticide residues, rinsed with running water to remove inedible parts, crushed and filtered with a food-grade crusher, pectinase is selected, the enzyme concentration is controlled to 0.3% (w / v), the pH value of the enzymolysis solution is adjusted to 4.8, and the temperature is 30°C. The crushed fruit slurry and the enzymolysis solution are mixed in a ratio of 1:1, placed in a constant temperature water bath, the enzymolysis temperature is controlled to 50°C, the enzymolysis time is 3 hours, and after the enzymolysis reaches a predetermined degree, it is heated to 80°C and maintained for 5 minutes to terminate the enzymolysis reaction. High-quality coffee beans are selected and ground into a fine powder suitable for cold brewing. The coffee powder and cold water are mixed in a ratio of 1:8. The mixture is mixed, the water temperature is controlled at 4°C, the mixture is placed in a sealed container and allowed to stand and soak in a refrigerator for 12 hours for cold extraction, and filtered with filter paper after the cold extraction. The enzymatically hydrolyzed fruit components and the cold-brewed coffee liquid are evenly mixed in a ratio of 1:5, and stirred at a rate of 300 rpm for 10 minutes using a stirrer, and the temperature is maintained at 20°C. The mixed liquid is poured into a freeze dryer tray with a thickness controlled at 1 cm, and pre-frozen at -40°C. The vacuum pump and heating system of the freeze dryer are started, and freeze-dried for 12 hours under the conditions of a vacuum degree of less than 20 Pa and a heating plate temperature of 40°C. In this embodiment, the fruit is fully enzymatically hydrolyzed to release a large amount of flavor substances. After being combined with the coffee liquid, the fruit flavor is more prominent and the taste of the coffee is relatively weakened.

[0075] Embodiment 4

[0076] This embodiment describes in detail a method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, wherein fresh, pest-free and moderately mature fruits are selected, rubbed in clean water to remove surface dust and pesticide residues, rinsed with running water to remove inedible parts, crushed and filtered with a food-grade crusher, pectinase is selected, the enzyme concentration is controlled to be 0.4% (w / v), the pH value of the enzymolysis solution is adjusted to 4.9, the crushed fruit slurry and the enzymolysis solution are mixed in a ratio of 1:1, placed in a constant temperature water bath, the enzymolysis temperature is controlled to be 55°C, the enzymolysis time is 3 hours, and after the enzymolysis reaches a predetermined degree, it is heated to 80°C and maintained for 5 minutes to terminate the enzymolysis reaction, high-quality coffee beans are selected, ground into a fine powder suitable for cold brewing, and the coffee powder and cold water are mixed in a ratio of 1:8 The mixture is mixed, the water temperature is controlled at 4°C, the mixture is placed in a sealed container and allowed to stand and soak in a refrigerator for 12 hours for cold extraction, and filtered with filter paper after the cold extraction. The enzymatically hydrolyzed fruit components and the cold-brewed coffee liquid are evenly mixed in a ratio of 1:5, and stirred at a rate of 300 rpm for 10 minutes using a stirrer, and the temperature is maintained at 20°C. The mixed liquid is poured into a freeze dryer tray, the thickness is controlled at 1 cm, and pre-frozen at -40°C. The vacuum pump and heating system of the freeze dryer are started, and freeze-dried for 12 hours under the conditions of a vacuum degree of less than 20 Pa and a heating plate temperature of 40°C. In this embodiment, the degree of fruit enzymatic hydrolysis is further deepened, and the fruit has a strong aroma. After mixing with the coffee liquid, the fruit flavor is strong, and coffee becomes an auxiliary taste.

[0077] Embodiment 5

[0078] This embodiment optimizes a method for preparing a cold-brewed freeze-dried coffee powder with fruit flavor, selects fresh, pest-free and moderately mature fruits, puts them in clean water and scrubs them to remove surface dust and pesticide residues, rinses them with running water to remove inedible parts, crushes them with a food-grade crusher and filters them, selects pectinase, controls the enzyme concentration to 0.5% (w / v), adjusts the pH value of the enzymolysis solution to 5.0, mixes the crushed fruit slurry with the enzymolysis solution in a ratio of 1:1, places them in a constant temperature water bath, controls the enzymolysis temperature to 60°C, and the enzymolysis time to 4 hours. After the enzymolysis reaches a predetermined degree, heats to 80°C and maintains for 5 minutes to terminate the enzymolysis reaction, selects high-quality coffee beans, grinds them into fine powder suitable for cold brewing, mixes the coffee powder with cold water in a ratio of 1:8, The water temperature is controlled at 4°C, and the mixture is placed in a sealed container and allowed to stand and soak in a refrigerator for 12 hours for cold extraction. After the cold extraction, the mixture is filtered with filter paper, and the enzymatically hydrolyzed fruit components and the cold-brewed coffee liquid are evenly mixed in a ratio of 1:5. The mixture is stirred at a rate of 300 rpm for 10 minutes using a stirrer, and the temperature is maintained at 20°C. The mixed liquid is poured into a freeze dryer tray with a thickness controlled at 1 cm, and pre-frozen at -40°C. The vacuum pump and heating system of the freeze dryer are started, and freeze-dried for 12 hours under the conditions of a vacuum degree of less than 20 Pa and a heating plate temperature of 40°C. In this embodiment, the fruit is fully enzymatically hydrolyzed, and a large amount of nutrients and flavor substances are released. After mixing with the coffee liquid, the taste of the fruit dominates and the taste of the coffee is almost covered up.

[0079] Embodiment 6

[0080] This embodiment describes in detail a method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, wherein fresh, pest-free and moderately mature fruits are selected, rubbed in clean water to remove surface dust and pesticide residues, rinsed with running water to remove inedible parts, crushed and filtered with a food-grade crusher, pectinase is selected, the enzyme concentration is controlled to be 0.35% (w / v), the pH value of the enzymolysis solution is adjusted to 4.7, the crushed fruit slurry and the enzymolysis solution are mixed in a ratio of 1:1, placed in a constant temperature water bath, the enzymolysis temperature is controlled to be 45°C, the enzymolysis time is 3.2 hours, and after the enzymolysis reaches a predetermined degree, it is heated to 80°C and maintained for 5 minutes to terminate the enzymolysis reaction, high-quality coffee beans are selected, ground into a fine powder suitable for cold brewing, and the coffee powder and cold water are mixed in a ratio of 1:8. The mixture is mixed, the water temperature is controlled at 4°C, the mixture is placed in a sealed container and allowed to stand and soak in a refrigerator for 12 hours for cold extraction, and filtered with filter paper after the cold extraction. The enzymatically hydrolyzed fruit components and the cold-brewed coffee liquid are evenly mixed in a ratio of 1:5, and stirred at a rate of 300 rpm for 10 minutes using a stirrer, and the temperature is maintained at 20°C. The mixed liquid is poured into a freeze dryer tray with a thickness controlled at 1 cm, and pre-frozen at -40°C. The vacuum pump and heating system of the freeze dryer are started, and freeze-dried for 12 hours under the conditions of a vacuum degree of less than 20 Pa and a heating plate temperature of 40°C. In this embodiment, the degree of fruit enzymatic hydrolysis is moderate, and the release of flavor substances and nutrients is relatively balanced. After mixing with the coffee liquid, the flavors of coffee and fruit reach a good balance.

[0081] In summary, by adjusting the parameters of the enzymatic hydrolysis reaction, cold-brewed freeze-dried coffee powder with different fruit flavors and tastes can be prepared to meet the diverse needs of consumers. Through fine fruit raw material pretreatment and bio-enzymatic hydrolysis technology, the natural flavor substances and nutrients in the fruit are successfully released and perfectly integrated with the cold-brewed coffee liquid, which not only retains the original mellow taste and aroma of the coffee, but also gives the coffee a unique fruit flavor, making the flavor levels of the coffee more rich and diverse.

[0082] 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 method for preparing cold-brewed freeze-dried coffee powder with fruit flavor, characterized in that: The specific steps of this method include: S1. Pretreatment of fruit raw materials: S1.

1. Raw material selection: Select fresh fruits that are free of pests and diseases and are moderately mature; S1.2, Washing and removing impurities: Put the selected fruits into clean water, scrub to remove dust and pesticide residues on the surface, and rinse with running water, while removing the inedible parts on the surface of the fruits; S1.3 Crushing: Use a food-grade crusher or blender to crush the cleaned fruits. For fruits with a harder texture and stronger flavor, use a stronger crusher for preliminary crushing. For fruits with a softer texture and more delicate flavor, use a blender or squeezer. Filter the crushed fruits to remove impurities and solid particles. S2. Biological enzymatic treatment: S2.

1. Preparation of enzymatic hydrolysate: Select biological enzymes according to the type and characteristics of the fruit, and prepare the enzymatic hydrolysate in a certain proportion, while adjusting the pH value of the enzymatic hydrolysate to the optimal action range of the enzyme; S2.2, mixed enzymolysis: evenly mix the filtered fruit juice with the prepared enzymolysis solution so that the enzyme can fully contact and act on the macromolecular substances in the fruit; S2.3, enzymatic hydrolysis reaction: placing the mixed solution in a constant temperature water bath or enzymatic hydrolysis reactor, and controlling the reaction temperature and time; S2.4, termination of enzymatic hydrolysis: when the enzymatic hydrolysis reaction reaches a predetermined degree, the enzymatic hydrolysis reaction is terminated by heating; S3. Cold brew coffee preparation: S3.

1. Coffee bean grinding: Select high-quality coffee beans and use a grinder to grind them into fine powder suitable for cold brewing; S3.2, cold extraction: mix the ground coffee powder and cold water in a certain proportion, and place the mixture in a low temperature environment and let it soak for cold extraction; S3.3, Filtration: After the cold brew is completed, use filter paper or filter mesh to filter the coffee liquid to remove coffee grounds and impurities; S4, Mixing and Drying: S4.1, mixing: mixing the enzymatically hydrolyzed fruit ingredients and the cold brewed coffee liquid evenly in a certain proportion; S4.2, stirring and blending: Use a blender to fully stir the mixture to fully blend the fruit ingredients with the coffee liquid; S4.3, freeze drying: pour the mixed solution into the tray of the freeze dryer for pre-freezing. After the mixed solution is completely frozen, start the vacuum pump and heating system of the freeze dryer to perform freeze drying in a low-temperature vacuum environment; S5. Packaging and storage: S5.

1. Packaging: Select packaging materials with good sealing properties, moisture-proof and oxidation-proof properties to package the freeze-dried coffee powder; S5.2, Labels and instructions: Affix product labels and instructions to the packaging, indicating the product name, ingredients, production date, shelf life and storage conditions; S5.

3. Storage and transportation: Store the packaged coffee powder in a cool, dry and ventilated place, avoid direct sunlight and high temperature environment, and maintain the integrity and stability of the packaging during transportation.

2. The method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In the step S2.1, the biological enzyme is pectinase, the enzyme concentration is controlled at 0.1%-0.5% (w / v), and the pH value of the enzymatic solution is adjusted to 4.5-5.

0.

3. The method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In the step S2.2, the crushed fruit pulp and the enzymatic hydrolysate are evenly mixed in a ratio of 1:1 to 1:

2.

4. The method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In step S2.3, the mixed solution is placed in a constant temperature water bath or an enzymolysis reactor, and the enzymolysis temperature is controlled to be 40° C.-60° C., and the enzymolysis time is 2-4 hours.

5. The method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In step S2.4, when the enzymatic hydrolysis reaches a predetermined degree, the enzymatic hydrolysis reaction is terminated by heating to 80-85° C. and maintaining for 5 minutes.

6. The method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: The ground coffee powder in step S3.2 is mixed with cold water in a ratio of 1:8 to 1:12, and the water temperature is controlled at 4° C. The mixture is placed in a sealed container and allowed to stand and soak in a refrigerator for 12-24 hours for cold extraction.

7. The use of the method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In the step S4.1, the enzymatically hydrolyzed fruit components and the cold brewed coffee liquid are evenly mixed in a ratio of 1:5 to 1:

10.

8. The use of the method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In the step S4.2, a stirrer is used to stir at a speed of 300 rpm for 10 minutes, and the temperature is maintained at 20-25° C. during the stirring process to avoid loss of flavor substances due to high temperature.

9. The use of the method for preparing cold-brewed freeze-dried coffee powder with fruit flavor according to claim 1, characterized in that: In the step 4.3, the mixed solution is poured into the tray of the freeze dryer, the thickness is controlled between 1-2 cm, the temperature is controlled at -40°C for pre-freezing treatment until the mixed solution is completely frozen, the vacuum pump and heating system of the freeze dryer are started, and the freeze drying treatment is carried out under the conditions that the vacuum degree is lower than 20Pa and the temperature of the heating plate is controlled at 40-60°C, and the drying time is set to 12-24 hours.