AU2020101926A4 - Beer brewed with waxberries and brewing method - Google Patents

Abstract

The present invention relates to a beer brewed with waxberries and a brewing method. The beer brewed with waxberries in the present invention includes the following raw materials in percent by weight: 62-69% of waxberry, 18-22% of barley malt, 12-15% of wheat malt, 0.4-0.7% of caramel malt, 0.5-0.8% of yeast and 0.1-0.4% of hop. The beer brewed with waxberries is obtained by preparation of waxberry juice, mashing of malts, lautering, boiling, cooling, main fermentation and post-fermentation. The waxberry juice is added during the boiling and before the post-fermentation respectively. The present invention adds the waxberry juice in two separate times, so that a waxberry flavor can be further retained in beer. During the fermentation, carbohydrates in the waxberries can be fully utilized by a yeast, which effectively avoids loss of nutrients of the waxberries from a preparation process aspect, and retains the waxberry flavor to the greatest extent. The brewed beer brewed with waxberries not only has the unique ester aroma and mellowness of a wheat beer, but also has a light fruit aroma of waxberries. 16

Description

BEER BREWED WITH WAXBERRIES AND BREWING METHOD

TECHNICAL FIELD The present invention belongs to the technical field of beer brewing, and relates to a beer brewed with waxberries and a brewing method.

BACKGROUND Beer is an alcoholic beverage with a long history which is brewed with water, malt and hops as main raw materials through fermentation with a yeast strain. The beer contains a variety of amino acids, vitamins, low molecular weight sugars, inorganic salts and various enzymes. These nutrients can be easily absorbed by a human body. The low molecular weight sugars and amino acids in the beer can be easily digested and absorbed, and can generate a lot of heat in the body, so beer is called "liquid bread". In addition, unique aroma of hops and delicate fragrance of malt give the beer a very unique flavor. Myrica rubra is a Myricaceae tree plant and named Yangmei since its fruit has a shape similar to Shuiyangzi and tastes like plum. Its fruit, waxberry, is one of Chinese special fruits which is praised by a poet that "one waxberry is worth a thousand dollars from a first thought". In areas of Jiangsu and Zhejiang, there is also a saying that "waxberry triumphs litchi". The waxberry fruit is bright in color, rich in juice, sweet and sour in taste, and high in nutritional value. Waxberry is generally ripe in May, and picked mostly around the Dragon Boat Festival. A high quality waxberry pulp contains a sugar content of 12-13%, an acid content of 0.5-1.1%, an abundant amount of cellulose, mineral elements and vitamins and a certain amount of protein, fat, pectin and 8 kinds of amino acids that are beneficial to the human body. The levels of calcium, phosphorus and iron in the fruit are more than 10 times higher than those of other fruits. The waxberry has functions of producing body fluid to quench thirst, promoting astringent intestines to stop diarrhea, harmonizing stomach to stop vomiting, promoting digestion and diuresis and can be used to relieve dizziness and muscle and joint pains caused by overwork. With improvement of pursuit of life, beer products have become increasingly abundant, and various fruit beers obtained by adding fruit juice for fermentation or by soaking fruits have emerged. A Chinese patent document CN103666906A (application number: 201310369100.7) discloses a preparation process for a beverage fermented with waxberry and wort, including production of waxberry juice, mashing of barley malt, wort boiling, addition of hops and the waxberry juice, fermentation with mixed waxberry and maltjuices, filtering and filling of fermented beverages. The beverages fermented with mixed materials of this invention are bright in color, fresh in taste, and low in alcohol, and at the same time, relieve heat stroke and boredom, quench thirst and promote blood circulation and metabolic circulation. Traditional fruit beers are mostly brewed with barley malt and caramel malt as raw materials, which result in a relatively monotonous beer aroma and relatively poor foam retention. Moreover, addition of juice in one time creates a high osmotic pressure for the yeast, which is not beneficial to yeast growth and leads to a slightly lighter fruit aroma for fruit beer.

SUMMARY In order to solve the problems of the prior technology, the present invention provides a beer brewed with waxberries and a brewing method. The beer brewed with waxberries of the present invention has a unique mouthfeel with moderate sweetness and sourness, and drinking in a moderate amount increases appetite and is beneficial to health. The technical solutions of the present invention are as follows: A beer brewed with waxberries, including the following raw materials in percent by weight: 62 69% of waxberry, 18-22% of barley malt, 12-15% of wheat malt, 0.4-0.7% of caramel malt, 0.5 0.8% of yeast and 0.1-0.4% of hop. Preferably, the beer brewed with waxberries includes the following raw materials in percent by weight: 64-68% of waxberry, 18-21% of barley malt, 12-14% of wheat malt, 0.5-0.7% of caramel malt, 0.5-0.7% of yeast and 0.2-0.4% of hop. Preferably, the beer brewed with waxberries includes the following raw materials in percent by weight: 66.5% of waxberry, 19% of barley malt, 13% of wheat malt, 0.6% of caramel malt, 0.6% of yeast and 0.3% of hop. The beer brewed with waxberries in the present invention is obtained by preparation of waxberry juice, mashing of malts, lautering, boiling, cooling, main fermentation and post fermentation. The waxberry juice is added during the boiling and before the post-fermentation respectively. A brewing method of the above-mentioned beer brewed with waxberries includes the following steps: step Sl. preparation of waxberry juice: removing stems of fresh and mature waxberries, soaking and washing in salt water, crushing pulps, pressing and filtering to obtain the waxberry juice; step S2. preparation of wort: mixing barley malt, wheat malt and caramel malt, mashing, lautering, boiling and cooling to obtain the wort, where the waxberry juice in step S Iis added during boiling; step S3. fermentation and post-treatment: pitching yeast to the wort prepared in step S2 for main fermentation, adding the waxberry juice in step Sl for post-fermentation when a diacetyl content of a fermentation broth drops below 0.1 mg/L, and filtering to obtain the beer brewed with waxberries.

According to the present invention, it is preferred that, in step Si, specific steps of the preparation of waxberry juice are as follows: step (1): selecting and cleaning: selecting mature and intact fresh waxberries, removing stems, soaking in salt water with a concentration of 33-35 g/L for 30-40 min, and rinsing with water; step (2): crushing: crushing waxberries with a mechanical method to separate pulps from endocarps and crushing pulps to 2-3 mm to facilitate juice obtaining; step (3): pre-boiling: pre-boiling crushed waxberries for 8-12 min to such an extent that the pulps are soft but still holding a complete shape, so as to inactivate enzymes in the waxberries and prevent oxidation; step (4): beating to pastes: beating pre-boiling waxberries at three stages with a screen having pore sizes of 1.2 mm, 0.8 mm and 0.5 mm in sequence respectively, where each stage is followed by filtering; step (5): hot pressing and secondary pressing: heating waxberry pastes obtained after beating to 64-66°C, pressing the pastes to obtain juice, where hot pressing aims to obtain soluble solids from pomace as many as possible to reduce a sugar content of in it, and then extracting the pomace with water at 35-38°C in a pomace-to-water mass ratio of 1:(1-2) for 20-40 min, and performing secondary pressing to increase a juice yield by 5-10%; step (6): clarifying: add a pectinase to pressed waxberry juice in an amount of 0.01-0.03% of the mass of the waxberries, enzymatically hydrolyzing at 34-36°C for 1 h; step (7): filtering: fine filtering clarified waxberry juice; step (8): adjusting sugar and acid contents: adding a white granulated sugar to filtered waxberry juice to adjust a sugar content, mixing malic acid and citric acid in a mass ratio of 1:3 before adjusting an acid content, so that a soluble solid content in the waxberry juice is >1loP and the pH is 5.5-5.7; where the sugar is added to achieve a required alcohol content of a finished beer, the citric acid is the mildest and most delicious with a relatively low cost among all organic acids, the malic acid tastes soft and has a long residence time, and the pH after adjusting the acid content should be similar to that of wheat wort; step (9): sterilizing: quickly heating the waxberry juice obtained after the adjusting sugar and acid contents to 100-120°C, performing instantaneous sterilization for 25 s, and then cooling to 37 39°C to prevent destroy of nutrients in the juice to obtain the waxberry juice. During preparation of the waxberry juice of the present invention, clarifying is carried out to avoid influence of pulp residues on growth of yeast, so as to retain flavor and nutrients of waxberries to the greatest extent. According to the present invention, it is preferred that, in step S2, the specific steps of the preparation of wort are as follows: step (1): crushing: mixing barley malt, wheat malt and caramel malt, and crushing raw materials on a roller mill at a speed of 160-180 r/min; step (2): mashing: mashing in a mash tun with materials and water in a mass ratio of 1:(3-4), where mashing-in is carried out at 43-45°C which is held for 15-25 min, a temperature is increased to 51-53°C and held for 30-45 min, increased to 64-66°C and held for 60-75 min and then increased to 77-79°C and held for 10-20 min, to obtain the mashes; step (3): lautering: allowing the mashes to stand still in lauter tun to settle spent grains on a filter sieve for lautering to obtain a first wort, and then sparging the spent grains, mixing water for sparging the spent grains with the first wort, so that a sugar content of a mixed wort is 10-14°P; step (4): boiling: adding the mixed wort into a wort kettle and boiling for 70-90 min, where hops are added during the boiling, and the waxberry juice obtained in step Siis added in an amount of 75-85% of the total mass of the waxberry juice 5-15 min before an end of the boiling; step(5): cooling: removing hot coagulum from boiled wort, cooling the boiled wort to 19-20°C and, at the same time, oxygenating to an oxygen content of 5-8 mg/L to obtain a wort for fermentation with pH of 5.5-5.7 and a sugar content of 10-15°P. More preferably, in step (4), hops are added for a first time when the boiling is carried out for 10 min, for a second time when the boiling is carried out for 30 min, and for a third time 10 minutes before an end of the boiling. According to the present invention, it is preferred that, in step S3, specific steps of the fermentation and the post-treatment are as follows: adding a yeast to the wort prepared in step S2 for main fermentation at 19.5-20.5°C, sealing a fermentation tank with a pressure below 0.15 MPa when a sugar content of a fermentation broth drops below 5°P, transferring to a post-fermentation tank when a diacetyl content of the fermentation broth drops below 0.1 mg/L, adding remaining waxberry juice, fermenting at -1°C to 0°C for 10 d, removing bottom yeast slurry and condensed solids to obtain an original beer, sterilizing by filtration to obtain the beer brewed with waxberries. Further preferably, the yeast is a fermentation broth of slant yeast after step propagations. Further preferably, the sterilizing by filtration is carried out with a 0.2 tm filter membrane. Further preferably, the beer brewed with waxberries has an alcohol content of 4-7% vol. The waxberry juice in the present invention is added in separate two times, where 75-85% of the waxberry juice is added for a first time to enrich nutrients of the wort and ensure vigorous growth of the yeast, and the remaining waxberry juice is added for a second time to improve sweetness of the finished beer and enable flavor of the waxberry juice to be further retained in beer, so that the finished beer has a more prominent waxberry flavor and sweeter tastes. The present invention has the following technical features: The present invention obtains the beer brewed with waxberries using a wheat beer as a base beer while the wheat beer has a unique ester aroma and a slightly sour taste. Use of the wheat beer can reduce cost on one hand and improve the flavor of the beer brewed with waxberries on the other hand. At the same time, the present invention adds the waxberry juice in two separate times, where a first addition is carried out 5-15 min before the end of the boiling, and a second addition is carried out when the diacetyl content of the fermentation broth drops below 0.1 mg/L before post fermentation, so that the waxberry flavor can be further retained in beer. During the fermentation, carbohydrates in the waxberries can be fully utilized by the yeast, which effectively avoids loss of nutrients of the waxberries from a preparation process aspect, and retains the flavor of the waxberries to the greatest extent. Appropriate adjustments are also made on ratios of materials, so that the brewed beer brewed with waxberries not only has the unique ester aroma and mellowness of the wheat beer, but also has a light fruit aroma of waxberries. Beneficial effects: The beer brewed with waxberries prepared by the present invention is clear and transparent without impurities, has a unique mouthfeel, moderate sour and sweetness, long foam retention, white and fine foams, and a harmonious and balanced taste. The beer of the present invention not only has original aromas of malt and hops in a beer, promotes digestion and absorption, and accelerates metabolism in the body, but also integrates sweet, sour and refreshing mouthfeel, fruit aroma of waxberries and effects of anti-cancer. Drinking of the beer in a moderate amount increases appetite and is beneficial to health. The present invention also proposes a method for brewing a beer brewed with waxberries, which has simple operations, requires simple and available materials with a low cost, and thereby is suitable for a larger range of applications.

DETAILED DESCRIPTION The present invention is further described in detail below with reference to specific examples, but the protection scope of the present invention is not limited to this: Experimental methods designed in the examples, unless otherwise specified, are all conventional experimental operations in the field; and raw materials involved in the examples, unless otherwise specified, are all common commercial products. The yeast involved in the examples is a common commercial product, which is activated and propagated according to the product specification. Example 1 A beer brewed with waxberries had the following raw materials in percent by weight: 64.2% of waxberry, 20% of barley malt, 14% of wheat malt, 0.7% of caramel malt, 0.7% of yeast and 0.4% of hop. A brewing method of the above beer brewed with waxberries included the following steps:

Step S1. preparation of waxberry juice: stems of fresh and mature waxberries were removed. The waxberries were soaked and washed in salt water. The pulps were crushed, pressed and filtered. The specific steps were as follows: step (1): selecting and cleaning: mature and intact fresh waxberries were selected and stems were removed. The waxberries were soaked in salt water with a concentration of 35 g/L for 30 min, and then rinsed with water; step (2): crushing: the waxberries were crushed with a mechanical method to separate pulps from endocarps. The pulps were crushed to 2-3 mm to facilitate juice obtaining; step (3): pre-boiling: crushed waxberries were pre-boiled for 10 min to such an extent that the pulps were soft but still holding a complete shape, so as to inactivate enzymes in the waxberries and prevent oxidation; step (4): beating to pastes: pre-boiled waxberries were beaten at three stages with a screen having pore sizes of 1.2 mm, 0.8 mm and 0.5 mn in sequence respectively, where each stage was followed by filtering; step (5): hot pressing and secondary pressing: waxberry pastes obtained after beating were heated to 65°C, pressed to obtain juice, where hot pressing aimed to obtain soluble solids from pomace as many as possible to reduce a sugar content of the pomace. Then the pomace was extracted with water at 35°C in a pomace-to-water mass ratio of 1:1.4 for 20 min, and secondary pressing was performed; step (6): clarifying: a pectinase was added to pressed waxberry juice in an amount of 0.01% of the mass of the waxberries for enzymatical hydrolyzation at 35°C for 1 h; step (7): filtering: clarified waxberry juice was fine filtered with a plate and frame filter; step (8): adjusting sugar and acid contents: a white granulated sugar was added to filtered waxberry juice to adjust a sugar content. Malic acid and citric acid were mixed in a mass ratio of 1:3 and used to adjust an acid content, so that a soluble solid content in the waxberry juice was >11P and the pH was 5.5; step (9): sterilizing: the waxberry juice obtained after the adjusting sugar and acid contents was quickly heated to 100°C for 25 s to achieve instantaneous sterilization, and then cooled to 38°C to prevent destroy of nutrients in the juice to obtain the waxberry juice. Step S2. preparation of wort: barley malt, wheat malt and caramel malt were mixed, mashed, filtered, boiled and cooled to obtain the wort, where the waxberry juice in step S Iwas added during boiling. The specific steps were as follows: step (1): crushing: barley malt, wheat malt and caramel malt were mixed, and stirred with an appropriated amount of water. Raw materials were crushed on a roller mill at a speed of 160 r/min; step (2): mashing: mashing was carried out in a mashing tun with materials and water in a mass ratio of 1:3.5, where mashing-in was carried out at 44°C which was held for 15 min. A temperature was slowly increased to 52°C and held for 30 min, slowly increased to 65°C and held for 60 min and then slowly increased to 78°C and held for 10 min, to obtain mashes; step (3): lautering: the mashes were allowed to stand still in lauter tun to settle spent grains on a filter sieve for lautering to obtain a first wort. Then the spent grains were sparged, and water for sparging the spent grains was mixed with the first wort, so that a sugar content of a mixed wort was looP; step (4): boiling: the mixed wort was added into a wort kettle and boiled for 90 min. Hops were added during boiling where hops were added for a first time when the boiling was carried out for 10 min, for a second time when the boiling was carried out for 30 min, and for a third time 10 minutes before an end of the boiling. The waxberry juice obtained in step Si was added in an amount of 75% of the total mass of the waxberry juice 15 min before the end of the boiling; step (5): cooling: hot coagulum was removed from boiled wort. The boiled wort was cooled to 19-20°C with a plate heat exchanger and, at the same time, the wort was oxygenated with a Venturi tube to an oxygen content of 8 mg/L to obtain the wort for fermentation with pH 5.5 and a sugar content of 10-11°P; Step S3. fermentation and post-treatment: a fermentation broth of a yeast after activation culture was added to the wort prepared in step S2 for main fermentation at 19.5°C. When a sugar content of a fermentation broth dropped below 5°P, a fermentation tank was sealed with a pressure below 0.15 MPa. When a diacetyl content of the fermentation broth dropped below 0.1 mg/L, the broth was transferred to a post-fermentation tank, added with remaining waxberry juice, fermented at -1-0°C for 10 d. Bottom yeast slurry and condensed solids were removed to obtain an original beer. Sterilization by filtration was carried out with a 0.2 pm filter membrane to obtain a beer brewed with waxberries with an alcohol content of 4-5%vol. Example 2 A beer brewed with waxberries had the following raw materials in percent by weight: 66.5% of waxberry, 19% of barley malt, 13% of wheat malt, 0.6% of caramel malt, 0.6% of yeast and 0.3% of hop. A brewing method of the above beer brewed with waxberries included the following steps: Step Sl. preparation of waxberry juice: stems of fresh and mature waxberries were removed. The waxberries were soaked and washed in salt water. The pulps were crushed, pressed and filtered. The specific steps were as follows: step (1): selecting and cleaning: mature and intact fresh waxberries were selected and stems thereof were removed. The waxberries were soaked in salt water with a concentration of 34 g/L for 35 min, and then rinsed with water; step (2): crushing: the waxberries were crushed with a mechanical method to separate pulps from endocarps. The pulps were crushed to 2-3 mm to facilitate juice obtaining; step (3): pre-boiling: crushed waxberries were pre-boiled for 10 min to such an extent that the pulps were soft but still holding a complete shape, so as to inactivate enzymes in the waxberries and prevent oxidation; step (4): beating to pastes: pre-boiled waxberries were beaten at three stages with a screen having pore sizes of 1.2 mm, 0.8 mm and 0.5 mmin sequence respectively, where each stage was followed by filtering; step (5): hot pressing and secondary pressing: waxberry pastes obtained after beating were heated to 65°C and pressed to obtain juice, where hot pressing aimed to obtain soluble solids from pomace as many as possible to reduce a sugar content of the pomace. Then the pomace was extracted with water at 37°C in a pomace-to-water mass ratio of 1:1.6 for 30 min. Secondary pressing was performed; step (6): clarifying: a pectinase was added to pressed waxberry juice in an amount of 0.02% of the mass of the waxberries for enzymatical hydrolyzation at 35°C for 1 h; step (7): filtering: clarified waxberry juice was fine filtered with a plate and frame filter; step (8): adjusting sugar and acid contents: a white granulated sugar was added to filtered waxberry juice to adjust a sugar content. Malic acid and citric acid were mixed in a mass ratio of 1:3 and used to adjust an acid content, so that a soluble solid content in the waxberry juice was >11Bx and the pH was 5.6; step (9): sterilizing: the waxberry juice obtained after the adjusting sugar and acid contents was quickly heated to 110°C for 25 s to achieve instantaneous sterilization, and then cooled to 38°C to prevent destroy of nutrients in the juice to obtain waxberry juice. Step S2. preparation of wort: barley malt, wheat malt and caramel malt were mixed, mashed, lautered, boiled and cooled to obtain the wort, where the waxberry juice in step Sl was added during boiling. The specific steps were as follows: step (1): crushing: barley malt, wheat malt and caramel malt were mixed, and stirred with an appropriated amount of water. Raw materials were crushed on a roller mill at a speed of 170 r/min; step (2): mashing: mashing was carried out in a mashing tun with materials and water in a mass ratio of 1:3.5, where mashing-in was carried out at 44°C which was held for 20 min. A temperature was slowly increased to 52°C and held for 40 min, slowly increased to 65°C and held for 70 min and then slowly increased to 78°C and held for 20 min, to obtain mashes; step (3): lautering: the mashes were allowed to stand still in lauter tun to settle spent grains on a filter sieve for filtration to obtain a first wort. Then the spent grains were sparged, and water for sparging the spent grains was mixed with the first wort, so that a sugar content of a mixed wort was

12°P; step (4): boiling: the mixed wort was added into a wort kettle and boiled for 80 min. Hops were added during boiling where hops were added for a first time when the boiling was carried out for 10 min, for a second time when the boiling was carried out for 30 min, and for a third time 10 minutes before an end of the boiling when, at the same time, the waxberry juice obtained in step Si was added in an amount of 80% of the total mass of the waxberry juice; Step (5): cooling: hot coagulum was removed from boiled wort. The boiled wort was cooled to 19-20°C with a plate heat exchanger and, at the same time, the wort was oxygenated with a Venturi tube to an oxygen content of 8 mg/L to obtain the wort for fermentation with pH 5.6 and a sugar content of 12-13°P; Step S3. fermentation and post-treatment: a fermentation broth of a yeast after activation culture was added to the wort prepared in step S2 for main fermentation at 20°C. When a sugar content of a fermentation broth dropped below 5°P, a fermentation tank was sealed with a pressure below 0.15 MPa. When a diacetyl content of the fermentation broth dropped below 0.1 mg/L, the broth was transferred to a post-fermentation tank, added with remaining waxberry juice, fermented at -1-0°C for 10 d. Bottom yeast slurry and condensed solids were removed to obtain an original beer. Sterilization by filtration was carried out with a 0.2 pm filter membrane to obtain a beer brewed with waxberries with an alcohol content of 5-6%vol. Example 3 A beer brewed with waxberries had the following raw materials in percent by weight: 68.8% of waxberry, 18% of barley malt, 12% of wheat malt, 0.5% of caramel malt, 0.5% of yeast and 0.2% of hop. A brewing method of the above beer brewed with waxberries included the following steps: Step S1. preparation of waxberry juice: stems of fresh and mature waxberries were removed. The waxberries were soaked and washed in salt water. The pulps were crushed, pressed and filtered. The specific steps were as follows: step (1): selecting and cleaning: mature and intact fresh waxberries were selected and stems thereof were removed. The waxberries were soaked in salt water with a concentration of 33 g/L for 40 min, and then rinsed with water; step (2): crushing: the waxberries were crushed with a mechanical method to separate pulps from endocarps. The pulps were crushed to 2-3 mm to facilitate juice obtaining; step (3): pre-boiling: crushed waxberries were pre-boiled for 10 min to such an extent that the pulps were soft but still holding a complete shape, so as to inactivate enzymes in the waxberries and prevent oxidation; step (4): beating to pastes: pre-boiled waxberries were beaten at three stages with a screen having pore sizes of 1.2 mm, 0.8 mm and 0.5 mm in sequence respectively, where each stage was followed by filtering; step (5): hot pressing and secondary pressing: waxberry pastes obtained after beating were heated to 65°C, pressed to obtain juice, where hot pressing aimed to obtain soluble solids from pomace as many as possible to reduce a sugar content of the pomace. Then the pomace was extracted with water at 37°C in a pomace-to-water mass ratio of 1:2 for 40 min, and secondary pressing was performed; step (6): clarifying: a pectinase was added to pressed waxberry juice in an amount of 0.03% of the mass of the waxberries for enzymatical hydrolyzation at 35°C for 1 h; step (7): filtering: clarified waxberry juice was fine filtered with a plate and frame filter; step (8): adjusting sugar and acid contents: a white granulated sugar was added to filtered waxberry juice to adjust a sugar content. Malic acid and citric acid were mixed in a mass ratio of 1:3 and used to adjust an acid content, so that a soluble solid content in the waxberry juice was >1lBx and the pH was 5.7; step (9): sterilizing: the waxberry juice obtained after the adjusting sugar and acid contents was quickly heated to 120°C for 25 s to achieve instantaneous sterilization, and then cooled to 38°C to prevent destroy of nutrients in the juice to obtain the waxberry juice. Step S2. preparation of wort: barley malt, wheat malt and caramel malt were mixed, mashed, lautered, boiled and cooled to obtain the wort, where the waxberry juice in step S was added during boiling. The specific steps were as follows: step (1): crushing: barley malt, wheat malt and caramel malt were mixed, and stirred with an appropriated amount of water. Raw materials were crushed on a roller mill at a speed of 180 r/min; step (2): mashing: mashing was carried out in a mashing tun with materials and water in a mass ratio of 1:3.5, where mashing-in was carried out at 44°C which was held for 25 min. A temperature was slowly increased to 52°C and held for 45 min, slowly increased to 65°C and held for 75 min and then slowly increased to 78°C and held for 10 min, to obtain mashes; step (3): filtering: the mashes were allowed to stand still in lauter tun to settle spent grains on a filter sieve for filtration to obtain a first wort. Then the spent grains were sparged, and water for sparging the spent grains was mixed with the first wort, so that a sugar content of a mixed wort was 14°P; step (4): boiling: the mixed wort was added into a wort kettle and boiled for 90 min. Hops were added during boiling where hops were added for a first time when the boiling was carried out for 10 min, for a second time when the boiling was carried out for 30 min, and for a third time 10 minutes before an end of the boiling. The waxberry juice obtained in step Sl was added in an amount of 85% of the total mass of the waxberry juice 5 min before the end of the boiling; step (5): cooling: hot coagulum was removed from boiled wort. The boiled wort was cooled to 19-20°C with a plate heat exchanger and, at the same time, the wort was oxygenated with a Venturi tube to an oxygen content of 8 mg/L to obtain the wort for fermentation with pH 5.7 and a sugar content of 14-15°P; Step S3. fermentation and post-treatment: a fermentation broth of a yeast after activation culture was added to the wort prepared in step S2 for main fermentation at 20.5°C. When a sugar content of a fermentation broth dropped below 5°P, a fermentation tank was sealed with a pressure below 0.15 MPa. When a diacetyl content of the fermentation broth dropped below 0.1 mg/L, the broth was transferred to a post-fermentation tank, added with remaining waxberry juice, fermented at -1-0°C for 10 d. Bottom yeast slurry and condensed solids were removed to obtain an original beer. Sterilization by filtration was carried out with a 0.2 pm filter membrane to obtain a beer brewed with waxberries with an alcohol content of 6-7%vol. Experimental Example The beers made with waxberries brewed in Examples 1-3 were subjected to sensory and flavor evaluation. 1. Sensory evaluation 1.1 Sensory evaluation standards Rich and fine foams with long lasting time and foam retention >260 s, clear and transparent, light color, no obvious suspended matter or sediment, elegant fruit fragrance, light hop fragrance, rich ester fragrance, moderate sweet and sour taste, soft and smooth. 1.2 Sensory score Appearance, foam performance, aroma and beer taste of the beers brewed with waxberries were scored by trained tasters, with a full score of 10 points for each item. The scoring results were shown in Table 1. Table 1. Sensory evaluation scores of beers made with waxberries in Examples 1-3

Item Appearance Foam Aroma Taste Kind performance Example 9 points 10 points 9 points 8 points 1 clear and transparent, no white foams, no harmonious malt, hop delicate and refreshing, strong impurities, excellent light impurities, long and waxberry aromas, irritating mouthfeel, strong transmittance foam retention no peculiar odour mellowness Example 9 points 10 points 10 points 10 points 2 clear and transparent, no obvious white and fine fruit fragrance of moderate sweet and sour taste, suspended matter or sediment foams, long- waxberries, sour, sweet strong irritating mouthfeel, lasting time and soft aroma, relatively low bitterness and pleasant and slightly sour and sweet harmonious ester, malt mouthfeel, harmonious and and hop aromas balanced taste Example 10 points 8 points 9 points 9 points 3 pink yellow color, clear and white and fine slight fruit fragrance of delicate and refreshing, no transparent, no obvious foams, clean, waxberries and sweet peculiar taste, moderate suspended matter or sediment, long-lasting time and sour fragrance, bitterness an sourness excellent light transmittance, no obvious ester and fruit light scattering or loss of light aromas

The beers brewed with waxberries brewed by the present invention were clear and transparent, free of impurities, and had white and fine foams with long foam retention and long lasting time. The beers also had harmonious malt, hop and waxberry aromas with no peculiar odour, delicate and refreshing mouthfeel, moderate sourness and sweetness, and balanced and harmonious taste with no peculiar taste. 2. Flavor substance detection The major flavor substances in the beers made with waxberries brewed in Examples 1-3 were detected, and the results were shown in Table 2. Table 2. Contents of major flavor substances in the beers made with waxberries of Examples1 3 (unit: mg/L)

am Kind Example I Example 2 Example 3 Common wheat beer Ethyl formate 2.35 1.82 1.95 0.15 Ethyl acetate 24.64 23.45 23.12 19.44 Isobutyl acetate 0.39 0.33 0.28 0.16 Isoamyl acetate 3.22 2.50 2.71 1.17 Ethyl caproate 0.53 0.37 0.40 0.06 Ethyl octanoate 0.52 0.40 0.31 0.10 Isoamyl alcohol 83.23 82.07 81.35 79.01 N-propanol 23.25 25.31 26.45 24.78 Isobutanol 48.25 49.13 50.25 47.77 Acetaldehyde 2.21 2.10 2.09 2.08 DMS 0.03 0.03 0.04 0.04 Total acid (mL/lOOmL) 7.95 7.75 6.23 1.8 Lactic acid (ppm) 1148 1038 998 448 Trans-caryophyllene 1.41 1.42 1.41 0.5 Anthocyanin 84.9 85.3 85.2 50.6

It can be seen from the above results that, the beers made with waxberries brewed by the present invention had significantly higher contents of the flavor substances of ethyl formate, ethyl acetate, isoamyl acetate, ethyl caproate and ethyl octanoate, total acid, lactic acid, trans-caryophyllene and anthocyanin compared with the common wheat beer. The flavor of a beer was mainly determined by the flavor substances in the beer, thus, the beers brewed with waxberries of the present invention had superior flavor characteristics compared with the common wheat beer. The present invention provides a beer brewed with waxberries which not only has original aromas of malt and hops in a beer, promotes digestion and absorption, and accelerates metabolism in the body, but also integrates sweet, sour and refreshing mouthfeel, fruit aroma of waxberries and effects of anti-cancer. The present invention also provides a method for brewing a beer brewed with waxberries, which has simple operations, requires simple and available materials with a low cost, and thereby is suitable for a larger range of applications. Although the examples of the present invention have been illustrated and described, it should be understood that those of ordinary skill in the technology may make various modifications to the above examples without departing from the principle and spirit of the present invention, and the scope of the present invention is limited by the appended claims and their equivalents.

Claims (5)

1. What is claimed is: 1. A beer brewed with waxberries, comprising the following raw materials in percent by weight: 62-69% of waxberry, 18-22% of barley malt, 12-15% of wheat malt, 0.4-0.7% of caramel malt, 0.5 0.8% of yeast and 0.1-0.4% of hop.
2. 2. The beer brewed with waxberries according to claim 1, wherein the beer comprises the following raw materials in percent by weight: 64-68% of waxberry, 18-21% of barley malt, 12-14% of wheat malt, 0.5-0.7% of caramel malt, 0.5-0.7% of yeast and 0.2-0.4% of hop.
3. 3. A method of brewing the beer brewed with waxberries according to claim 1, comprising the following steps: step S1. preparation of waxberry juice: removing stems of fresh and mature waxberries, soaking and washing in salt water, crushing pulps, pressing and filtering to obtain the waxberry juice; step S2. preparation of wort: mixing barley malt, wheat malt and caramel malt, mashing, lautering, boiling and cooling to obtain the wort, wherein the waxberry juice in step S Iis added during boiling; step S3. fermentation and post-treatment: adding a yeast to the wort prepared in step S2 for main fermentation, adding the waxberry juice in step S1for post-fermentation when a diacetyl content of a fermentation broth drops below 0.1 mg/L, and filtering to obtain the beer brewed with waxberries.
4. 4. The method of brewing according to claim 3, wherein in step Si, specific steps of the preparation of waxberry juice are as follows: step (1): selecting and cleaning: selecting mature and intact fresh waxberries, removing stems, soaking in salt water with a concentration of 33-35 g/L for 30-40 min, and rinsing with water; step (2): crushing: crushing waxberries with a mechanical method to separate pulps from endocarps and crushing pulps to 2-3 mm; step (3): pre-boiling: pre-boiling crushed waxberries for 8-12 min; step (4): beating to pastes: beating pre-boiled waxberries at three stages with a screen having pore sizes of 1.2 mm, 0.8 mm and 0.5 mmin sequence respectively, wherein each stage is followed by filtering; step (5): hot pressing and secondary pressing: heating waxberry pastes obtained after beating to 64-66°C, pressing the pastes to obtain juice, and then extracting pomace with water in a pomace-to water mass ratio of 1:(1-2) at 35-38°C for 20-40 min, and performing secondary pressing; step (6): clarifying: adding a pectinase to pressed waxberry juice in an amount of 0.01-0.03% of mass of the waxberries, enzymatically hydrolyzing at 34-36°C for 1 h; step (7): filtering: fine filtering clarified waxberry juice; step (8): adjusting sugar and acid contents: adding a white granulated sugar to filtered waxberry juice to adjust a sugar content, mixing malic acid and citric acid in a mass ratio of 1:3 before adjusting an acid content, so that a soluble solid content in the waxberry juice is >1loP and the pH is 5.5-5.7; step (9): sterilizing: quickly heating the waxberry juice obtained after the adjusting sugar and acid contents to 100-120°C, performing instantaneous sterilization for 25 s, and then cooling to 37 39°C to obtain the waxberry juice; wherein in step S2, specific steps of the preparation of wort are as follows: step (1): crushing: mixing barley malt, wheat malt and caramel malt, and crushing raw materials on a roller mill at a speed of 160-180 r/min; step (2): mashing: mashing in a mashing tun with materials and water in a mass ratio of 1:(3-4), wherein mashing-in is carried out at 43-45°C which is held for 15-25 min, a temperature is increased to 51-53°C and held for 30-45 min, increased to 64-66°C and held for 60-75 min and then increased to 77-79°C and held for 10-20 min, to obtain mashes; step (3): lautering: allowing the mashes to stand still in lauter tun to settle spent grains on a filter sieve for filtration to obtain a first wort, and then sparging the spent grains, mixing water for sparging the spent grains with the first wort, so that a sugar content of a mixed wort is 10-14°P; step (4): boiling: adding the mixed wort into a wort kettle and boiling for 70-90 min, wherein hops are added during the boiling, and the waxberry juice obtained in step Si is added in an amount of 75-85% of the total mass of the waxberry juice 5-15 min before an end of the boiling; step (5): cooling: removing hot coagulum from boiled wort, cooling the boiled wort to 19-20°C and, at the same time, oxygenating to an oxygen content of 5-8 mg/L to obtain the wort for fermentation with pH of 5.5-5.7 and a sugar content of 10-15°P; wherein in step (4), hops are added for a first time when the boiling is carried out for 10 min, for a second time when the boiling is carried out for 30 min, and for a third time 10 minutes before an end of the boiling; wherein in step S3, specific steps of the fermentation and the post-treatment are as follows: adding a yeast to the wort prepared in step S2 for main fermentation at 19.5-20.5°C, sealing a fermentation tank with a pressure below 0.15 MPa when a sugar content of a fermentation broth drops below 5°P, transferring to a post-fermentation tank when a diacetyl content of the fermentation broth drops below 0.1 mg/L, adding remaining waxberry juice, fermenting at -l°C to 0°C for 10 d, removing bottom yeast slurry and condensed solids to obtain an original beer, sterilizing by filtration to obtain the beer brewed with waxberries.
5. 5. The method of brewing according to claim 4, wherein the yeast is a fermentation broth of slant yeast after step propagations; wherein the sterilizing by filtration is carried out with a 0.2 pm filter membrane; wherein the beer brewed with waxberries has an alcohol content of 4-7% vol.