CN104263571B - A kind of red date sheep milk beer and preparation technology thereof - Google Patents

Abstract

The invention discloses a jujube goat milk beer, which is made from jujube goat milk lactic acid liquid and beer original brew at a volume ratio of 1:0.5 to 1:2; wherein the red jujube goat milk lactic acid liquid is made from the following raw materials in parts by weight: 100 parts of goat milk, 10-15 parts of red date juice, 0.3-0.5 parts of compound lactic acid bacteria, 4-8 parts of sweetener, 0.35-0.5 parts of stabilizer; the original brewing of beer is made of the following raw materials in parts by weight: 150 parts of wort juice , 0.075-0.15 parts of hops, 0.3-0.75 parts of beer yeast. Also disclosed is the preparation process of the jujube goat milk beer, using goat milk, malt and red dates as raw materials, respectively carrying out lactic acid fermentation and alcoholic fermentation, and then mixing and carrying out post-ripening fermentation of lactic acid. The jujube goat's milk beer of the present invention not only has good stability, but also has a pure color and a good taste. It not only has the flavor of yogurt and beer, but also has the taste of jujube and carbon dioxide, and is more suitable for the taste of consumers. The new type of drink has a broad market prospect.

Description

A kind of jujube goat milk beer and its preparation process

technical field

The invention relates to a jujube goat milk beer and a preparation process thereof, belonging to the technical field of food fermentation.

Background technique

In my country, fresh milk has a long history of being made into various dairy products, and milk wine is very popular because of its rich nutritional value and unique flavor. Foaming milk wine is milk beer. Traditional milk beer uses milk, hops, and malt as the main raw materials. It is made into milk beer with rich nutrition and unique flavor through lactic acid fermentation and alcohol fermentation. Because it has the characteristics of yogurt, beer and carbonated drinks Flavor has become a new type of healthy drink.

In recent years, with the continuous emergence of milk problems, more and more consumers have begun to feel a sense of fear towards milk, and people are looking for new milk sources that are more nutritious and of higher quality. As a new type of milk source, goat milk has attracted more and more attention because of its rich nutritional value. Goat milk contains more than 200 kinds of nutrients and biologically active substances, including 64 kinds of lactic acid, more than 20 kinds of amino acids, and 20 kinds of vitamins. There are many kinds of minerals and 25 kinds of minerals, and goat milk is recognized as the closest to human milk in the world. Red dates are rich in VC, minerals and 18 kinds of amino acids needed by the human body. It is recorded in "Compendium of Materia Medica": "Red dates are sweet in taste and warm in nature. Producing body fluid, treating deficiency." Modern medical research has proved that jujube has nutritional and health effects such as promoting blood circulation, delaying aging, dilating blood vessels, and preventing cardiovascular diseases.

With the increase of people's demand for goat milk, various goat milk products such as goat milk powder, goat milk cheese and goat milk yogurt are rushing to the market. And take goat's milk as the goat's milk beer of main raw material to rarely appear on the market at present.

The Chinese patent "A Brewing Method of Milk Beer" (CN100392056C) discloses a method that uses whey of cow's milk, mare's milk or goat's milk as raw material, adds lactose yeast to the whey for fermentation, and then adds fermented whey Malt and hops are brewed according to the beer fermentation process to make milk beer. This brewing method realizes the full and reasonable comprehensive utilization of waste, but because the fat and protein content in whey is too low, it cannot reflect the comprehensive and balanced nutritional value of goat milk, and the smell of goat milk cannot be well covered.

Chinese patent "a kind of milk beer drink and its preparation method" (CN1594526A) discloses a kind of milk beer drink, after yogurt, stabilizer and sweetener are mixed in proportion, add beer homogenization, then add beer yeast liquid and mix Evenly, ferment, and you get it. In this method, alcoholic fermentation is carried out after mixing yoghurt and beer, so the carbon dioxide and alcohol produced in the fermentation process may cause the protein in the yoghurt to precipitate and the milk fat to rise, making the nutritional components in the prepared milk beer unstable.

Contents of the invention

The object of the present invention is to provide a red date goat's milk beer and its preparation process. Goat's milk, malt and red dates are used as raw materials to carry out lactic acid fermentation and alcoholic fermentation respectively, and then mix in proportion to carry out after-ripening fermentation. During the preparation process of this product, the full fermentation of lactic acid and alcohol respectively improves the stability of milk beer; the secondary homogenization adopted, the strict control of the degree of wort, the addition of CMC-Na, pectin, sucrose ester, etc. All the measures can effectively prevent the precipitation of milk fat, avoid the floating and stratification of milk fat in the product, and increase the stability of milk beer. In addition, the added jujube juice can alleviate to a certain extent the inhibition of beneficial bacteria caused by high acidity in the later stage of fermentation, increase the number of bacteria, and can also remove the smell of goat milk, greatly improving the flavor of the product. Give the product more nutritional and health functions. This product has the flavor of yogurt and beer, the aroma of jujube juice and the taste of carbon dioxide, and removes the smell of goat milk to the greatest extent. It has strong stability and has broad market prospects.

To achieve the above object, the present invention adopts the following technical solutions:

A kind of jujube goat's milk beer, which is made from jujube goat's milk lactic acid liquid and beer brewing at a volume ratio of 1:0.5 to 1:2;

Wherein, the jujube goat milk lactic acid liquid is made from the following raw materials in parts by weight:

100 parts of goat milk, 10-15 parts of red date juice, 0.3-0.5 parts of compound lactic acid bacteria, 4-8 parts of sweetener, 0.35-0.5 parts of stabilizer;

The original beer is made from the following raw materials in parts by weight:

150 parts of wort, 0.075-0.15 parts of hops, 0.3-0.75 parts of brewer's yeast.

The compound lactic acid bacteria are mixed by mass ratio (1～2):(1～2) of Lactobacillus bulgaricus and Streptococcus thermophilus;

The dried red dates used to prepare red date juice are commercially available products, the manufacturer is Leling Shouxing Jujube Industry Co., Ltd., and the trade name is Xinjiang special product Hetian jujube;

Preferably, Lactobacillus bulgaricus and Streptococcus thermophilus are mixed at a mass ratio of 1:1; the compound lactic acid bacteria is a commercially available product, the manufacturer is Beijing Chuanxiu International Trade Co., Ltd., and the trade name is Chuanxiu Lactobacillus Yogurt Starter;

The wort is made of malt and water in a mass ratio (1-1.5): 5;

The sweetener is white granulated sugar or sucrose;

The stabilizer is mixed with 0.1-0.2 parts of carboxymethylcellulose sodium (CMC-Na), 0.15-0.2 parts of pectin and 0.1 parts of sucrose ester;

Described brewer's yeast (Sac-charomycescerevisiae), is commercially available product, is purchased from Angel Yeast Co., Ltd., and trade name is Angel beer active dry yeast;

The preparation technology of the jujube goat milk beer comprises the following steps:

(1) Weigh the raw materials according to the above weight parts, add the content of the peeled malt into water at 65-68°C, the mass ratio of malt to water is (1-1.5):5, keep the temperature and heat for 1-2h, Then heat up to 75-80°C, fully convert the starch into sugar, and filter to obtain the wort;

(2) Boil the wort, and add hops therein, measure the sugar content of the wort during the boiling process of the hops, until the sugar content of the wort drops to 1.5 ° P ~ 2 ° P;

(3) Wort precipitation cooling, after cooling the wort, pour it into the fermentation tank, add brewer's yeast, ferment, and seal the tank after the residual sugar content of the fermentation liquid drops to 4 degrees Baume, when the quality of diacetyl in the fermentation liquid is 100% When the beer content drops below 0.1%, the temperature is lowered to 0°C, the fermentation is stopped, and the post-storage time is at least two weeks to obtain the beer puree;

(4) Sterilize the goat milk and jujube juice, mix and stir evenly, dissolve the sweetener and stabilizer in hot water, sterilize and cool them, add them to the jujube goat milk mixture, sweetener, stabilizer and The mass volume ratio of water is 1:10-40 (g/ml), then add compound lactic acid bacteria, stir evenly, and ferment at 40-45°C for 20-30 hours to obtain jujube goat milk lactic acid liquid;

(5) Add the original beer brew obtained in step (3) into the jujube goat milk lactic acid liquid in step (4), the volume ratio of the red date goat milk lactic acid liquid to the original beer brew is 1:0.5～1:2, in order to make The texture and taste of the product are more integrated and homogenized, so that the texture of the milk beer is more uniform, the taste has no sense of conflict, and stratification is prevented. Post-ripening fermentation is carried out at 4°C to make the flavor better, that is, red date goat milk beer .

In the step (2), the hops are added in three times. After the wort is boiled for 10 minutes, 20% of the hops are added, and then 60% of the hops are added after boiling for 30 minutes. Boil for 20 minutes, measure the sugar content of the wort with a sugar meter, if the sugar content is too high, add water and continue boiling until the sugar content drops to 1.5°P-2°P. If the sugar content of the wort is too high and the alcohol content is too high, the goat milk protein is easily denatured, resulting in unstable products. The sugar content of the juice is measured to control the alcohol content.

In the step (3), the beer yeast is activated and expanded in the wort before being added, and the weight ratio of the wort to the beer yeast is 5-10:1 to obtain the working strain.

In the step (3), the fermentation process conditions are as follows: the fermentation temperature is 9° C., the fermentation time is 3-4 days, then the temperature is raised to 11° C., and the pressure in the tank is kept at 0.12 MPa.

In the step (4), the sterilization method of goat milk, jujube juice, sweetener and stabilizer aqueous solution is to filter the material to be sterilized and pour it into a sterilized Erlenmeyer flask, seal it with a tampon, and put it into High-pressure steam sterilizer, sterilize at 95°C for 10-15min, then cool to 45°C.

In the described step (4), the preparation method of jujube juice is to select the high-quality non-rotten dried jujube with pitting for use, clean it and place it in a beater, add 4 times the water of the volume (g/mL) for beating, and then add 4 Doubling the volume (g/mL) of water and 0.2% pectinase in the raw material mass percentage of jujube were hydrolyzed at 30°C for 3 hours, and then filtered with gauze. Jujube juice was extracted by enzymatic hydrolysis to increase the content of VC.

In the step (5), the homogeneous conditions are 60° C. and 30 MPa.

In the step (5), the post-ripening fermentation condition is 4° C. for 6 hours.

Preferably, in step (4), the stabilizer is 0.2 part of CMC-Na, 0.15 part of pectin and 0.1 part of sucrose ester.

Preferably, in step (4), the fermentation condition of the mixed liquid of goat milk and red dates is 42° C. for 24 hours.

Preferably, in the step (5), the volume ratio of the jujube goat milk lactic acid liquid to the beer brewing is 1:1˜1:1.5.

In the invention, the goat's milk is made into goat's milk beer through secondary fermentation, which not only makes full use of the rich nutritional value of the goat's milk, but also has the low alcohol content of beer and the delicious taste of carbonated drinks. Since the casein of goat milk is less than that of milk, and the fat particles are one-third of that of milk, the taste is more delicate and refreshing after fermentation, and the composition is more stable. At the same time, the addition of red dates can not only eliminate the smell of goat milk itself, but also has health care functions such as promoting blood circulation in the human body, promoting body fluids to quench thirst, beautifying the skin, and improving human immunity. It is a fashionable, healthy and green new health care drink with broad market prospects.

The present invention adopts the method for organoleptic evaluation to determine the addition of jujube juice:

Take four 200ml Erlenmeyer flasks, add 50ml of sterilized goat milk respectively, homogenize, add jujube juice of 8%, 10%, 12% and 14% of the volume percentage of goat milk, and stir evenly. The mass percentage of goat milk is 4% white sugar, 0.2% CMC-Na, 0.15% pectin and 0.1% sucrose ester, mixed with hot water, sterilized and cooled, and then added to the jujube goat milk mixture , adding compound lactic acid bacteria, stirring evenly, putting it into a constant temperature incubator at 42° C. to ferment for 24 hours to obtain jujube goat milk lactic acid liquid. Then mix jujube goat milk lactic acid liquid and beer puree at a ratio of 1:1, homogenize at 30 MPa, put in 4°C for post-ripening fermentation for 6 hours, and then perform sensory evaluation. The experimental results are shown in Table 1:

The impact of the addition of table 1 jujube juice on the taste of the product

The present invention increases the addition amount of jujube juice to 15% and above, and finds that when the content of jujube juice is more than 15%, the product will have bad flavor due to too strong jujube flavor. Through sensory evaluation, it is determined that the addition amount of jujube juice is 10-15%.

The present invention adopts the sedimentation rate of measuring product to determine the addition of CMC-Na and pectin in the stabilizer:

Take four labeled 200ml Erlenmeyer flasks, add 50ml of sterilized goat milk respectively, homogenize, add sterilized jujube juice accounting for 12% of the volume percentage of goat milk, stir well, and respectively account for the mass percentage of goat milk White granulated sugar with a content of 4%, 0.1% sucrose ester, different amounts of CMC-Na and pectin are dissolved in hot water, sterilized and cooled, added to the red date and goat milk mixture, added with compound lactic acid bacteria, stirred evenly, put into Ferment at 42° C. for 24 hours in a constant temperature incubator to obtain red date goat milk lactic acid liquid. Then, the jujube goat milk lactic acid liquid and the beer puree were mixed evenly at a ratio of 1:1, homogenized at 30 MPa, and then put into 4°C for post-ripening fermentation for 6 hours to obtain the product. Then take 10 mL of milk beer prepared with different contents of CMC-Na and pectin, put them into centrifuge tubes, centrifuge at 3500 r/min for 10 min, pour off the supernatant, measure the mass of the precipitate as m ₁ , and place the precipitate in Dry at 105°C to constant weight, measure its mass m ₂ , and calculate the ratio of the total solid content in the sample, and use the sedimentation rate SR (sedimentation rate) to express the stability of the system. The larger the SR value, the worse the system stability .

SR＝m ₁ /m ₂

The impact of different contents of CMC-Na and pectin on product stability is shown in Table 2:

The impact of CMC-Na and pectin in different addition amounts of table 2 on product stability

Through sensory evaluation, it is determined that the addition amount of CMC-Na and pectin in the stabilizer is 0.25%-0.4%.

The present invention adopts the method for sensory evaluation to determine the addition of sweetener:

Take four labeled 200ml Erlenmeyer flasks, add 50ml of sterilized goat milk respectively, homogenize, add sterilized jujube juice accounting for 12% of the volume percentage of goat milk, stir evenly, and respectively account for the mass percentage of goat milk Dissolve 0.2% CMC-Na, 0.15% pectin, 0.1% sucrose ester and white granulated sugar with different contents, sterilize and cool with hot water, add red dates and goat milk mixture, then add compound lactic acid bacteria, stir evenly, put Ferment in a constant temperature incubator at 42°C for 24 hours to obtain red date goat milk lactic acid liquid. Then mix the jujube goat milk lactic acid liquid and beer puree evenly at a ratio of 1:1, homogenize at 30MPa, put it in 4°C for post-ripening fermentation for 6 hours, and then perform sensory evaluation. The experimental results are shown in Table 3:

Table 3 The impact of the addition of white granulated sugar on the taste of the product

Through sensory evaluation, it is determined that the added amount of sweetener is 2-8%.

Beneficial effects of the present invention:

(1) The present invention carries out lactic acid fermentation and alcoholic fermentation respectively, then mixes in proportion to carry out post-ripening fermentation of lactic acid. The milk beer made in this way can avoid protein precipitation and milk fat rise due to the production of carbon dioxide and alcohol during the alcoholic fermentation process, and improve the stability of the milk beer. Carrying out fermentation separately can fully carry out lactic acid fermentation and alcoholic fermentation, and the color is pure and the taste is positive, so that the flavor of yogurt and beer is fully integrated into the finished product, the flavor of jujube and the killing taste of carbon dioxide.

(2) The present invention measures the degree of wort during the boiling process of hops, and strictly controls the degree of wort, so that the alcohol content is controlled within the alcohol stability range of goat milk, thereby avoiding the deterioration of goat milk due to excessive alcohol. Product instability due to protein denaturation.

(3) CMC-Na and pectin added in the product of the present invention can improve the viscosity of milk beer, and the sucrose esters added can prevent the separation of goat milk milk fat under acidic conditions and increase the stability of milk beer; Secondary homogenization maximizes the density of fat globules and prevents fat globules from floating up. It not only makes the texture of milk beer more uniform and has no conflicting taste, but also prevents stratification and increases the stability of the product.

(4) The jujube juice added in the present invention during the lactic acid fermentation of goat milk can alleviate to a certain extent the inhibition of beneficial bacteria caused by excessive acidity in the later stage of fermentation, increase the number of bacteria, and can also remove goat milk. Improve the product flavor by reducing the smell of mutton, and at the same time endow the product with more nutritional and health functions.

(5) The jujube goat milk beer prepared by the present invention has the advantages of rich protein, amino acid and vitamins, low alcohol and low calorie value, and good stability. The nutritional combination of jujube and goat milk will better cater to the health concept of consumers. Coupled with the aroma of malt wine, it makes the product more fashionable. It is a new type of drink that is healthy, nutritious, green and healthy. It is more in line with the concept of consumers pursuing health and has a broad market value.

detailed description:

The present invention will be further elaborated below through specific examples. It should be noted that the following descriptions are only for explaining the present invention, and do not limit its content.

Example 1

Preparation of jujube goat milk beer

The process is as follows:

(1) Preparation of beer brewing:

Grind 300g of selected high-quality malt to separate the skin from the content without breaking the content, then heat the water to 65°C, put the peeled malt content into the water, the quality of malt and water The ratio is 1:5, keep the temperature at 65°C and heat for 1 hour, then raise the temperature to 78°C and filter with gauze to obtain wort. Add 1.25g of hops to the wort three times, first boil the wort for 10 minutes, then add hops with 20% of the total mass of hops, continue to boil for 30 minutes, then add hops with 60% of the total mass of hops, and then add hops after the 50th minute of boiling Hops with a total mass of 20% continue to boil for 20 minutes. Use a sugar meter to measure the sugar content. If the sugar content is too high, add water and continue to boil until the sugar content drops to 1.5°P-2°P. After the wort is cooled, it is poured into a fermenter, and then 7.5g of beer yeast is added. Before adding the beer yeast, it is activated and expanded in 70mL of wort to obtain working strains. The wort tank can not be full for more than 24 hours. After the tank is full for 24 hours, the slag should be discharged in time. The fermentation temperature is 9°C, and it is maintained for 4 days, and then the temperature is raised to 11°C as the main fermentation temperature, and the pressure is 0.12MPa. When the residual sugar content drops to 4 Baume degrees, the cans are sealed, because diacetyl will produce bad flavors in beer, so when the mass percentage of diacetyl in the fermentation liquid drops below 0.1%, the beer is considered to be fermented mature, and it must be slow Lower the temperature to 0° C. to prevent the yeast from continuing to ferment, and store for at least two weeks to obtain beer puree.

(2) Preparation of jujube goat milk lactic acid liquid:

What this example uses is the Laoshan milk goat of Sanxi milk goat farm in Tai'an City. Take 1000mL of fresh goat milk, pour it into a sterilized 1000mL Erlenmeyer flask after filtration, add a cotton plug, and put it into a high-pressure steam sterilizer. The pot was sterilized at 95°C for 15 minutes, homogenized, and cooled to 45°C. Pour 120mL of sterilized jujube juice into the sterilized goat milk, stir evenly with a sterilized glass rod, dissolve 40g of white sugar, 2g of CMC-Na, 1.5g of pectin and 1g of sucrose ester in hot water , after sterilizing and cooling, add it to the jujube and goat milk mixed solution, mix evenly, and then mix 5 g of Lactobacillus bulgaricus and Streptococcus thermophilus in a mass ratio of 1:1 on the ultra-clean workbench. Lactic acid bacteria granules were added to 1000mL sterilized goat milk mixture, stirred evenly, put into a constant temperature incubator at 42°C for 24 hours of fermentation, and red date goat milk lactic acid liquid was obtained.

Take four 200ml Erlenmeyer flasks, add 200ml red dates and goat milk lactic acid solution respectively, and then add beer puree according to the volume ratio of 1:0.5, 1:1, 1:1.5, 1:2, mix evenly, and Homogenize at 30MPa, place at 4°C for post-ripening fermentation for 6 hours, and then perform sensory evaluation. The experimental results are shown in Table 4:

Table 4 The effect of the ratio of jujube goat milk lactic acid liquid and beer puree on the taste of the product

The jujube goat milk beer prepared by Example 1 of the present invention has the following characteristics:

(1) The taste of the product is unique and delicate, and the color and fragrance are excellent.

(2) It has the milk flavor of yogurt, the malt flavor of beer, the flavor of dates and the mouthfeel of carbonated drinks.

The jujube goat milk beer of the present invention is a new type of healthy, nutritious, green and health-care drink. The product has the advantages of rich protein, amino acid and vitamins, low alcohol and low calorific value, and is more in line with the concept of consumers pursuing health. The perfect combination of the nutritional value of red dates and goat milk endows the product with more nutritional and health care functions, coupled with the aroma of malt wine, not only removes the smell of goat milk, but also has a more unique taste, making the product more fashionable and attractive The eyes of more consumers have broad market prospects and good economic benefits.

Example 2

Preparation of jujube goat milk beer

(1) Preparation of beer brewing:

Grind 350g of selected high-quality malt to separate the skin from the content without breaking the content, then heat the water to 68°C, put the peeled malt content into the water, the quality of malt and water The ratio is 1.5:5, keep the temperature at 68°C and heat for 1 hour, then raise the temperature to 80°C and filter with gauze to obtain wort. Add 1.0g of hops to the wort three times, first boil the wort for 10 minutes, then add hops with 20% of the total mass of hops, continue to boil for 30 minutes, add hops with 60% of the total mass of hops, and add the total hops after boiling for 50 minutes The hops with 20% quality continue to boil for 20 minutes, measure the sugar content with a sugar meter, if the sugar content is too high, add water and continue to boil until the sugar content drops to 1.5°P-2°P. After the wort is cooled, it is poured into a fermenter, and then 4.4g of brewer's yeast is added. Before adding the brewer's yeast, it is activated and expanded in 40mL of wort to obtain a working strain. The wort tank should not be full for more than 24 hours. After the tank is full for 24 hours, the slag should be discharged in time. The fermentation temperature is 9°C, maintained for 3 days, and then raised to 11°C as the main fermentation temperature, and the pressure is 0.12MPa. When the residual sugar content drops to 4 Baume degrees, the cans are sealed, because diacetyl will produce bad flavors in beer, so when the mass percentage of diacetyl in the fermentation liquid drops below 0.1%, the beer is considered to be fermented mature, and it must be slow Lower the temperature to 0° C. to prevent the yeast from continuing to ferment, and store for at least two weeks to obtain beer puree.

(2) Preparation of jujube goat milk lactic acid liquid:

What this example uses is the Laoshan dairy goat of Tai’an City Sanxi Milk Goat Farm. Take 1000mL of fresh goat’s milk, pour it into a sterilized 1000mL Erlenmeyer flask after filtration, add a cotton plug, and put it into a high-pressure steam sterilizer. The pot was sterilized at 95°C for 15 minutes, homogenized after sterilization, and cooled to 45°C. Pour 100mL of sterilized jujube juice into the sterilized goat milk, stir evenly with a sterilized glass rod, add 60g of white sugar, 1.5g of CMC-Na, 1.5g of pectin and 1g of sucrose ester After dissolving and sterilizing in hot water, add red dates and goat milk mixture, mix evenly, and mix 3 g of Lactobacillus bulgaricus and Streptococcus thermophilus in a mass ratio of 2:1 on a clean bench. The granules were added to 1000mL of sterilized goat milk mixture, stirred evenly, put into a constant temperature incubator at 42°C for 24 hours of fermentation, and the red date goat milk lactic acid liquid was obtained. Then add the beer puree at a ratio of 1:1 by volume, put it in 4°C for post-ripening fermentation for 6 hours, and obtain the product.

Example 3

Preparation of jujube goat milk beer

(1) Preparation of beer brewing:

Grind 330g of selected high-quality malt to separate the skin from the content, and the content is broken but not broken, then heat the water to 66°C, put the peeled malt content into the water, the quality of malt and water The ratio is 1.3:5, keep the temperature at 66°C and heat for 2 hours, then raise the temperature to 75°C and filter with gauze to obtain wort. Add 0.8g of hops to the wort three times, first boil the wort for 10 minutes, then add hops accounting for 20% of the total mass of hops, continue to boil for 30 minutes, then add hops accounting for 60% of the total mass of hops, add after the 50th minute of boiling The hops accounting for 20% of the total mass of hops, continue to boil for 20 minutes, measure the sugar content with a sugar meter, if the sugar content is too high, add water and continue to boil until the sugar content drops to 1.5°P-2°P. After the wort is cooled, it is poured into the fermenter, and then 4.8g of brewer's yeast is added. Before adding the brewer's yeast, it is activated and expanded in 40mL of wort to obtain working strains. The wort tank should not be full for more than 24 hours. After the tank is full for 24 hours, the slag should be discharged in time. The fermentation temperature is 9°C, maintained for 3 days, and then raised to 11°C as the main fermentation temperature, and the pressure is 0.12MPa. When the residual sugar content drops to 4 Baume degrees, the cans are sealed, because diacetyl will cause bad flavor in beer, so when the diacetyl drops below 0.1%, the beer is considered to be fermented mature, and the temperature should be slowly lowered to 0°C to prevent yeast The bacteria continue to ferment, and the post-storage time is at least two weeks to obtain beer puree.

(2) Preparation of jujube goat lactic acid liquid:

In this example, Laoshan milk goats from Sanxi Milk Goat Farm in Tai’an City were used. Fresh goat milk was taken in 1000 mL, filtered and homogenized, poured into a sterilized 1000 mL Erlenmeyer flask, added with a cotton plug, and placed in high-pressure steam Sterilize at 95°C for 15 minutes, then cool to 45°C. Pour 150mL of sterilized jujube juice into the sterilized goat's milk, stir evenly with a sterilized glass rod, mix 80g of white granulated sugar, 2g of CMC-Na, 2g of pectin and 1g of sucrose ester with hot water After dissolving and sterilizing in water, add it to the jujube goat milk mixture, mix evenly, and mix 4g of Lactobacillus bulgaricus and Streptococcus thermophilus in a mass ratio of 1:2 on a clean bench. The granules are added to 1000ml of sterilized goat milk mixture, stirred evenly, put into a constant temperature incubator at 42°C to ferment for 24 hours, and the jujube goat milk lactic acid liquid is obtained. Then add beer stock at a volume ratio of 1:1, homogenize at 30 MPa, put it in 4°C for post-ripening fermentation for 6 hours, and obtain the product.

Sensory evaluation was carried out on the jujube goat milk beer prepared in Examples 2 and 3, and the results are shown in Table 2.

The product mouthfeel evaluation table that table 2 embodiment 2,3 prepares

Claims (8)

1. A red date goat milk beer is characterized in that it is made of red date goat milk lactic acid liquid and beer brewing at a volume ratio of 1:0.5 to 1:2; wherein the red date goat milk lactic acid liquid is made of the following raw materials in parts by weight become: 100 parts of goat milk, 10-15 parts of red date juice, 0.3-0.5 parts of compound lactic acid bacteria, 4-8 parts of sweetener, 0.35-0.5 parts of stabilizer; The original beer is made from the following raw materials in parts by weight: 150 parts of wort juice, 0.075-0.15 parts of hops, 0.3-0.75 parts of brewer's yeast; The compound lactic acid bacteria are mixed by mass ratio (1～2):(1～2) of Lactobacillus bulgaricus and Streptococcus thermophilus; The sweetener is white granulated sugar or sucrose; The stabilizer is a mixture consisting of 0.1 to 0.2 parts of sodium carboxymethylcellulose, 0.15 to 0.2 parts of pectin and 0.1 part of sucrose ester; The preparation method is: (1) Weigh the raw materials by weight, add the malt peeled content into water at 65-68°C, the mass ratio of malt to water is (1-1.5): 5, keep the temperature and heat for 1-2h, then After heating up to 75-80°C, filter to obtain wort; (2) Boil the wort, and add hops therein, measure the sugar content of the wort during the boiling process, until the sugar content of the wort drops to 1.5 ° P ~ 2 ° P; (3) Pour the wort into the fermenter after cooling, add brewer's yeast, and ferment. After the residual sugar content of the fermented liquid drops to 4 degrees Baume, the can is sealed. When the mass percentage of diacetyl in the fermented liquid drops to 0.1 % below, stop the fermentation, after storage for at least two weeks, to obtain beer puree; (4) Sterilize the goat milk and jujube juice, mix them, mix the sweetener and stabilizer with hot water to dissolve and sterilize them, add them to the goat milk and jujube mixture, then add compound lactic acid bacteria to the mixture, and stir well , fermented at 40-45°C for 20-30h to obtain jujube goat milk lactic acid liquid; (5) Add the original brewed beer obtained in step (3) into the jujube goat milk lactic acid liquid in step (4), the volume ratio of the red date goat milk lactic acid liquid and the original beer brew is 1:1, homogenize and post-ripen Fermentation, that is. 2. the preparation technology of the described jujube goat's milk beer of claim 1 is characterized in that, comprises the following steps: (1) Weigh the raw materials by weight, add the malt peeled content into water at 65-68°C, the mass ratio of malt to water is (1-1.5): 5, keep the temperature and heat for 1-2h, then After heating up to 75-80°C, filter to obtain wort; (2) Boil the wort, and add hops therein, measure the sugar content of the wort during the boiling process, until the sugar content of the wort drops to 1.5 ° P ~ 2 ° P; (3) Pour the wort into the fermenter after cooling, add brewer's yeast, and ferment. After the residual sugar content of the fermented liquid drops to 4 degrees Baume, the can is sealed. When the mass percentage of diacetyl in the fermented liquid drops to 0.1 % below, stop the fermentation, after storage for at least two weeks, to obtain beer puree; (4) Sterilize the goat milk and jujube juice, mix them, mix the sweetener and stabilizer with hot water to dissolve and sterilize them, add them to the goat milk and jujube mixture, then add compound lactic acid bacteria to the mixture, and stir well , fermented at 40-45°C for 20-30h to obtain jujube goat milk lactic acid liquid; (5) Add the original brewed beer obtained in step (3) into the jujube goat milk lactic acid liquid in step (4), the volume ratio of the red date goat milk lactic acid liquid and the original beer brew is 1:1, homogenize and post-ripen Fermentation, that is; In the step (2), the hops are added in three times. After the wort is boiled for 10 minutes, hops accounting for 20% of the total weight of the hops are added, and after boiling for 30 minutes, hops accounting for 60% of the total weight of the hops are added. Add hops accounting for 20% of the total weight of hops after 50 minutes, and then boil for 20 minutes; In step (5), the homogeneous conditions are 60° C. and 30 MPa. 3. The preparation process of jujube goat milk beer as claimed in claim 2, characterized in that, in the step (3), the fermentation process conditions are: the fermentation temperature is 9°C, the fermentation time is 3-4 days, and then Raise the temperature to 11°C, continue the fermentation, and keep the pressure in the tank at 0.12MPa. 4. the preparation technology of jujube goat's milk beer as claimed in claim 2 is characterized in that, in described step (3), brewer's yeast carries out activation expansion cultivation in wort before adding, and the weight of wort and brewer's yeast The ratio is 5-10:1. 5. the preparation technology of red date goat's milk beer as claimed in claim 2 is characterized in that, in described step (4), the sterilization method of goat's milk, red date juice, sweetener and stabilizer aqueous solution is, will Filter the sterilized substance into a sterilized Erlenmeyer flask, seal it with a cotton plug, put it into a high-pressure steam sterilizer, sterilize at 95°C for 10-15min, and then cool to 45°C. 6. The preparation process of jujube and goat milk beer according to claim 2, characterized in that, in step (4), the fermentation condition of goat milk and jujube mixed liquid is 42°C for 24 hours. 7. The preparation process of jujube goat's milk beer as claimed in claim 2, characterized in that, in the step (4), the preparation method of jujube juice is as follows: the dried jujube after the pitting is cleaned and placed in a beater , add 4 times the volume of water for beating, then add 4 times the volume of water and 0.2% pectinase, perform enzymatic hydrolysis at 30°C for 3 hours, and filter to obtain the product. 8 . The preparation process of jujube goat milk beer according to claim 2 , characterized in that, in the step (5), the post-ripening fermentation condition is 4° C. for 6 hours.