Red bean ice wine and preparation method thereof

Abstract

The invention relates to red bean ice wine and a preparation method thereof. The red bean ice wine is prepared by taking natural wild red beans in Greater Khingan as a main raw material and white birch juice as an auxiliary food material through secondary fermentation. According to the red bean ice wine prepared by the method disclosed by the invention, the alcoholic strength is 38-52% (V / V); the sugar content is 0.06 g / L-0. 1g / L (W / W), and the product is in a transparent crystal color, keeps the taste of original fruits, and is pure in flavor, full and mellow in taste and rich in nutrition.

Description

A red bean ice wine and its preparation method Technical Field

[0001] This invention relates to an ice wine and its preparation method, specifically to a red bean ice wine and its preparation method. Background Technology

[0002] Red beans (Vaccinium vitis-idaea Linn.), also known as tooth bumps, are mainly distributed in the Changbai Mountains of Inner Mongolia and Jilin Province, and the eastern mountainous areas of the Greater Khingan Mountains in Heilongjiang Province in my country. Wild red bean fruits contain a large amount of vitamins, pigments, and proteins. Every 100 grams of fresh fruit contains 2.16 grams of protein, 0.16 grams of fat, 5.7 grams of carbohydrates, 12 milligrams of vitamin C, 2.2 grams of fruit acids, and 69.25 milligrams of red pigment. It also contains 6.2% reducing sugars and 2.2% organic acids.

[0003] Birch sap, a newly emerging plant-based beverage, is mainly distributed in the Changbai Mountains of Jilin Province, the eastern mountainous area of ​​the Greater Khingan Mountains in Heilongjiang Province, and the Greater Khingan Mountains in Inner Mongolia, China. It is also found in the Russian Far East, Japan, and northern Korea.

[0004] The Greater Khingan Mountains Forest Region of Inner Mongolia is located in the northeastern part of Inner Mongolia Autonomous Region, with geographical coordinates of 11°36'30"-125°24'00" east longitude and 47°03'20"-53°20'00" north latitude. It spans over 400 kilometers east to west and 1100 kilometers north to south, traversing two leagues and nine banners (cities) of Inner Mongolia. It connects with the Nenjiang Plain to the southeast, borders the Greater Khingan Mountains and its tributary, the Yilehuli Mountains, to the northeast (separated by the main ridge of the Greater Khingan Mountains and its branch, the Yilehuli Mountains), to the northeast (bordered by the Greater Khingan Mountains Forestry Company of Heilongjiang Province), to the west (bordered by the Hulunbuir Grassland), and to the north (separated by the Ergun River, bordered by Russia). It covers a total area of ​​106,000 square kilometers, with a forest coverage rate of 75.1%. The Greater Khingan Mountains Forest Region of Inner Mongolia is rich in wild economic plant resources, with diverse species and large reserves.

[0005] The Greater Khingan Mountains possess unique geographical advantages. The wild plant resources in the forest area are a type of green food, free from environmental pollution, and are currently popular in both domestic and international markets, with promising development prospects. Both red beans and birch sap are rich in vitamins and possess medicinal and health benefits. Currently, domestic research focuses heavily on blueberries, with less emphasis on red beans and birch sap. However, with rising living standards and increased acceptance of green foods, the demand for purely natural green beverages is gradually increasing. The production of red bean ice wine, with its pure flavor and full body, utilizes red bean and birch sap resources, opening up a new avenue that breaks away from traditional processes, adhering to the principle of preserving the original components of the wild fruits. Currently, this project is unexplored in China.

[0006] Most existing ice wines are made from fruits such as grapes and blueberries, and their alcohol content is generally around 12%. Technology for making ice wine from red beans is relatively scarce. Summary of the Invention

[0007] In view of this, the purpose of this invention is to provide a red bean ice wine and its preparation method, which combines red beans and birch sap to form a natural, pollution-free, green and healthy beverage with a unique flavor and rich nutrition.

[0008] To achieve the above objectives, the present invention provides a red bean ice wine, which is made by using natural wild red beans from the Greater Khingan Mountains as the main raw material and birch sap as an auxiliary ingredient through secondary fermentation.

[0009] As a preferred embodiment, the weight ratio of the wild red bean and birch sap is 8:(1.8-2).

[0010] As a preferred embodiment, the sensory indicators of the red bean ice wine are: aroma is a unique fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; and physicochemical indicators are: alcohol content of 38-52% (V / V) and sugar content of 0.06g / L-0.1g / L (W / W).

[0011] As a preferred embodiment, the sensory indicators of the red bean ice wine are: aroma is a unique fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; physicochemical indicators are: alcohol content of 42%-52% (V / V) or 38%-48% (V / V); and sugar content of 0.08g / L-0.1g / L (W / W).

[0012] The present invention also provides a method for preparing red bean ice wine, comprising the following steps: 1) picking wild red beans; 2) screening and removing impurities; 3) juicing; 4) taking the original juice of birch trees in the primeval forest of the Greater Khingan Mountains; 5) fermentation; 6) decomposition and filtration; wherein in step 1), the wild red beans are fruits between the Cold Dew and Frost's Descent periods, and the red bean fruits are in a frozen state.

[0013] As a preferred embodiment, step 4) specifically includes obtaining birch sap from the primeval forest of the Greater Khingan Mountains: selecting birch trees aged 15 to 20 years from the primeval forest of the Greater Khingan Mountains, obtaining birch sap in early April each year using a sterile drilling method, and immediately filtering it through a 0.22μm micropore to remove bacteria, thus obtaining birch sap; the soluble solids content in the birch sap is 3wt% to 5wt%, and the total flavonoid content is ≥0.1g / L.

[0014] As a preferred embodiment, in step 5), the fermentation specifically includes: fermenting the red bean juice in a sealed environment for the first step, and then adding birch sap for the second step of fermentation.

[0015] As a preferred embodiment, in step 5), the amount of birch sap added accounts for 18-22 wt% of the red bean juice.

[0016] As a preferred embodiment, in step 5), the temperature of the first fermentation step is 22℃~25℃, and the time is 2~3 months.

[0017] As a preferred embodiment, in step 5), the temperature of the second fermentation step is 17℃~25℃, and the time is 1~1.5 months.

[0018] As a preferred option, it also includes the steps of storing the ice wine obtained after decomposition and filtration in step 6) in underground tanks for at least one year, filling it into pasteurization tanks, and then bottling and sealing it.

[0019] Compared with the prior art, the present invention has the following beneficial effects: the sensory indicators of the red bean ice wine of the present invention are the special fruity aroma of red beans, which is harmonious and without any off-flavors; the body is full-bodied and the taste is mellow; the physicochemical indicators are an alcohol content of 38-52% (V / V) and a sugar content of 0.06g / L-0.1g / L (W / W).

[0020] This invention uses wild red beans and birch sap as the main raw materials, overcoming difficulties in production and breaking away from traditional processes, while adhering to the principle of not altering the original components of the wild fruits. Through multiple experiments, the optimal fermentation conditions and production process parameters were determined. The red beans and birch sap not only improve the single-component nature of the fruits but also achieve a complementary effect, enriching the nutritional content. Detailed Implementation

[0021] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description, in conjunction with preferred embodiments, provides a detailed explanation of the specific implementation methods, features, and effects of a red bean ice wine and its preparation method based on the present invention.

[0022] Some embodiments of the present invention provide a red bean ice wine, which is made by using natural wild red beans from the Greater Khingan Mountains as the main raw material, extracting the red bean juice, and using birch sap as an auxiliary ingredient through secondary fermentation.

[0023] In practice, the weight ratio of wild red beans to birch sap is 8:(1.8-2), and this ratio has been found to be optimal through multiple trials. 80% red bean juice retains the main style and fruitiness of the red bean ice wine, while 20% birch sap is used because birch sap contains active elements that promote optimal fermentation. A ratio higher or lower than this will affect the taste and quality of the wine.

[0024] In specific implementation, the sensory indicators of the red bean ice wine are: aroma is the special fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; physicochemical indicators are: alcohol content 38-52% (V / V); sugar content 0.06g / L-0.1g / L (W / W).

[0025] Furthermore, the sensory indicators of the red bean ice wine are: aroma is a unique fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; physicochemical indicators are: alcohol content 42%-52% (V / V) or 38%-48% (V / V); sugar content 0.08g / L-0.1g / L (W / W).

[0026] Some embodiments of the present invention also provide a method for preparing red bean ice wine, comprising the following steps: 1) picking wild red beans; 2) screening and removing impurities: screening the picked red bean fruits to remove leaves and other impurities, and rinsing them clean; 3) juicing: directly extracting red bean juice using a juicer, effectively preventing air from entering and reducing or preventing adverse changes in the color, aroma, and taste of the juice during the juicing process; 4) extracting sap from birch trees in the Greater Khingan Mountains: selecting birch trees aged 15-20 years in the Greater Khingan Mountains virgin forest, and extracting sap from them in early April each year (at the initial stage of sap flow) using a sterile drill. Birch sap is obtained using a microfiltration method. Immediately after collection, it is filtered through 0.22μm micropores for sterilization, yielding birch sap (soluble solids content 3wt%–5wt%, total flavonoid content ≥0.1g / L), ensuring the raw material is free of bacteria and nutrients are not lost. 5) Fermentation: The overall fermentation process consists of two steps. In the first step, the red bean juice obtained from juicing is placed in a fermentation tank, sealed, and the fermentation temperature is controlled between 22℃ and 25℃ for 2–3 months. For the purpose of fermenting red bean juice, the temperature can be slightly higher; below this temperature, the alcohol content will not be reached, and above this temperature, the product quality will deteriorate. Adding 18–22wt% birch sap during the second fermentation step is a key control point in the product process. The temperature should be between 17℃ and 22℃, and the fermentation time should be 1 to 1.5 months. Birch sap contains active elements. Through multiple experiments, the optimal fermentation conditions and production process parameters have been determined. Birch sap is not suitable for high-temperature fermentation; temperatures above this range can easily lead to product spoilage, while temperatures below this range will not achieve the desired fermentation effect. Practice has shown that adding birch sap increases the alcohol content by 5-7 degrees. Because birch sap contains active elements, it promotes fermentation and increases alcohol content. The brewing of red bean ice wine has its suitable fermentation temperature, and temperature control during fermentation is one of the keys to brewing high-quality wine. If the large amount of heat generated during fermentation is not dissipated in time, it can cause bacterial diseases and an increase in volatile acid content. Fermentation time and temperature directly affect the quality and flavor of the wine. To ensure a certain temperature is maintained during fermentation, a heating device can be installed in the fermentation tank. Specifically, the birch sap contains flavonoids and phenolic acids (such as gallic acid and caffeic acid), which have strong antioxidant properties, scavenge free radicals, reduce inflammatory responses, and protect the cardiovascular system; betulin and betulinic acid: triterpenoid compounds unique to birch trees, which have anti-inflammatory, antibacterial, and antioxidant effects, and studies have found that they have certain auxiliary effects on skin inflammation and intestinal mucosal protection; it contains 17 kinds of amino acids, including 8 essential amino acids (lysine, methionine, leucine, etc.), although the content is not high (total amino acids are about 50~100mg / L), but the variety is complete, supplementing the body's essential nitrogen source; it contains a variety of natural enzymes (such as amylase, protease, and catalase), which retain biological activity, help promote digestion, and enhance the body's metabolic capacity; it contains a small amount of plant polysaccharides, which have immunomodulatory and antioxidant effects, and enhance the body's resistance.

[0027] Pay attention to the hygiene of the fermentation workshop, ensure clean air, and frequently clean and disinfect production equipment and containers. In particular, a clear concept of aseptic technique must be established in the fermentation room.

[0028] 6) Decomposition and Filtration: The color of the fermented juice is decolored using a diatomaceous earth filter, and impurities are separated. Then, a plate-type precision filter with a 0.2-0.3 mesh is used for high-definition filtration. A distillation process is employed (avoiding high heat during distillation; maintain a gentle heat throughout, keeping the distillation pot temperature stable at 78-85℃ to prevent scorching and off-flavors; control the condenser water temperature at 10-15℃ to ensure complete steam condensation). After the entire process, the juice is clear and transparent. After all processes are completed, the product is stored in underground tanks for at least one year. The optimal storage conditions are generally 12℃-19℃, resulting in better product quality and taste. Before bottling, the product is sterilized at 85℃-95℃ (20-30 minutes) and then packaged.

[0029] In the above technical solution, this invention uses wild red beans and birch tree juice as the main raw materials, overcomes the difficulties in production, and breaks away from traditional processes, adhering to the principle of not altering the original components of the wild fruits. Through multiple experiments, the optimal fermentation conditions and production process parameters were determined. The red beans and birch tree juice change the single-component nature of one fruit, achieving a complementary effect between the two fruit components and enriching nutrition.

[0030] As a preferred option, step 1) requires harvesting the fruit between the Cold Dew and Frost's Descent season, when the red bean fruit is frozen. The harvesting season for red bean ice wine is a crucial element in the successful product development. During this season, the red bean fruit is ripe and plump, meeting the requirements for ice wine production. The fruit is frozen, and its components are at their optimal state, hence the name "red bean ice wine." When the temperature drops below freezing, the red bean plant senses the low-temperature signal and initiates a series of gene expressions, synthesizing a large amount of antifreeze proteins. These proteins can adhere to the surface of ice crystals, preventing further growth and spread of ice crystals, thus protecting the cell structure from being pierced by ice crystals. This is key to the survival of red bean fruit in a frozen state. Low temperatures induce the decomposition of large carbohydrate molecules such as starch within plant cells, converting them into soluble sugars such as glucose, fructose, and sucrose, as well as sugar alcohols such as mannitol and sorbitol. This is a classic "osmotic regulation" strategy. High concentrations of soluble sugars and sugar alcohols lower the freezing point of the cell sap, preventing intracellular freezing and maintaining cell turgor pressure, protecting the integrity of the cell membrane and organelles. This directly leads to a significant increase in the sugar content of red bean fruits, resulting in a sweeter taste and a richer flavor. Low-temperature stress increases the level of reactive oxygen species (ROS) in plants. To eliminate these harmful ROS, plants synthesize and accumulate large amounts of antioxidants, such as vitamin C, vitamin E, flavonoids, and polyphenolic compounds. These substances are crucial for improving the nutritional value and antioxidant capacity of the fruit. Amino acids such as proline also accumulate at low temperatures, and they also participate in osmotic regulation and protein structure protection. Therefore, the low-temperature (even freezing) environment during the Cold Dew and Frost's Descent periods actually puts a "stress" on red bean fruits. To cope with this stress, red bean fruits actively synthesize and accumulate a series of protective substances (such as antifreeze proteins, soluble sugars, and antioxidants), while reducing their own consumption, thus achieving a more ideal state in terms of the types and content of their nutrients. Wild red beans and birch sap are both iconic wild resources of the Greater Khingan Mountains; their fusion embodies the uniqueness of a "regional natural ingredient combination," which is the focus of this invention. Red bean ice wine has an alcohol content of 42% to 52%. This product is transparent and crystalline, retaining the original fruit flavor, pure taste, full and mellow mouthfeel, and rich nutrition.

[0031] The present invention will be described in detail below with reference to specific embodiments.

[0032] Example 1 This example provides a method for preparing red bean ice wine, including the following steps: 1) Harvesting red beans: Harvest the fruits between the Cold Dew and Frost's Descent, when the red bean fruits are in a frozen state; 2) Screening and removing impurities: Screen the harvested red bean fruits to remove leaves, impurities, etc., and rinse them clean; 3) Juicing: Extract red bean juice directly using a juicer.

[0033] 4) Obtaining birch sap from the primeval forest of the Greater Khingan Mountains: Select 20-year-old birch trees from the primeval forest of the Greater Khingan Mountains. In early April each year (the initial stage of sap flow), collect birch sap using a sterile drilling method. Immediately after collection, filter the sap through a 0.22μm micropore to remove bacteria, obtaining birch sap with a soluble solids content of 4wt% and a total flavonoid content of 0.1g / L; 5) Fermentation: The overall fermentation is divided into two steps. In the first step, 8kg of red bean juice is put into a fermentation tank, sealed, and fermented at 25℃ for 2 months; in the second step, 2kg of birch sap is added, and the temperature is 19℃ for 1 month; 6) Decomposition and filtration: Use a diatomaceous earth filter to decolorize the juice obtained in step 5) and separate the impurities. Then, use a plate-type precision filter for high-definition filtration with a 0.3 mesh. After distillation at 80℃, a clear and transparent ice wine is obtained.

[0034] 7) After storing the ice wine obtained in step 6) in underground tanks for three years, it is then transferred to sterilization tanks for pasteurization (95°C, 25 minutes) before bottling and sealing.

[0035] The red bean ice wine prepared in this embodiment has an alcohol content of 45% (V / V) and a sugar content of 0.08 g / L (W / W).

[0036] Example 2 The difference between this example and Example 1 is that the amount of birch sap added in step 5) of this example is 1.8 kg.

[0037] The red bean ice wine prepared in this embodiment has an alcohol content of 46% (V / V) and a sugar content of 0.07 g / L (W / W).

[0038] Example 3 The difference between this example and Example 1 is that the amount of birch sap added in step 5) of this example is 1.9 kg.

[0039] The red bean ice wine prepared in this embodiment has an alcohol content of 45% (V / V) and a sugar content of 0.075 g / L (W / W).

[0040] Example 4 The difference between this example and Example 1 is that in step 5) of this example, 15-year-old birch trees from the primeval forest of the Greater Khingan Mountains are selected.

[0041] The red bean ice wine prepared in this embodiment has an alcohol content of 44% (V / V) and a sugar content of 0.085 g / L (W / W).

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A red bean ice wine, characterized in that, The red bean ice wine is made from natural wild red beans from the Greater Khingan Mountains as the main ingredient and birch sap as an auxiliary ingredient through secondary fermentation.

2. The red bean ice wine as described in claim 1, characterized in that, The weight ratio of the wild red bean to the birch sap is 8:(1.8-2).

3. The red bean ice wine as described in claim 1, characterized in that, The sensory indicators of the red bean ice wine are: aroma is a unique fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; physicochemical indicators are: alcohol content 38-52% (V / V); sugar content 0.06g / L-0.1g / L (W / W).

4. The red bean ice wine as described in claim 3, characterized in that, The sensory indicators of the red bean ice wine are: aroma is a special fruity aroma of red beans, harmonious and without any off-flavors; full-bodied and mellow taste; physicochemical indicators are: alcohol content 42%-52% (V / V) or 38%-48% (V / V); sugar content 0.08g / L-0.1g / L (W / W).

5. A method for preparing red bean ice wine according to any one of claims 1-4, characterized in that, The process includes the following steps: 1) picking wild red beans; 2) screening and removing impurities; 3) juicing; 4) extracting the original juice from birch trees in the primeval forest of the Greater Khingan Mountains; 5) fermentation; 6) decomposition and filtration. In step 1), the wild red beans are fruits that are harvested between the Cold Dew and Frost's Descent solar terms, and the red bean fruits are in a frozen state.

6. The preparation method according to claim 5, characterized in that, In step 4), the specific steps of obtaining birch sap from the primeval forest of the Greater Khingan Mountains include: selecting birch trees aged 15 to 20 years from the primeval forest of the Greater Khingan Mountains, and obtaining birch sap in early April each year using a sterile drilling method. After collection, the sap is immediately filtered through a 0.22 μm micropore for sterilization to obtain birch sap. The soluble solids content in the birch sap is 3wt% to 5wt%, and the total flavonoid content is ≥0.1g / L.

7. The preparation method according to claim 5, characterized in that, In step 5), the fermentation specifically includes: fermenting the red bean juice in a sealed environment for the first step, and then adding birch sap for the second step of fermentation.

8. The preparation method according to claim 7, characterized in that, In step 5), the amount of birch sap added accounts for 18-22 wt% of the red bean juice.

9. The preparation method according to claim 7, characterized in that, In step 5), the temperature of the first fermentation step is 22℃~25℃ and the time is 2~3 months; the temperature of the second fermentation step is 17℃~25℃ and the time is 1~1.5 months.

10. The preparation method according to claim 7, characterized in that, It also includes the steps of storing the ice wine obtained after decomposition and filtration in step 6) in underground tanks for at least one year, filling it into pasteurization tanks, and then bottling and sealing it.