A processing technology of fruit fermented beer

Abstract

The application relates to the field of beer processing, and particularly discloses a processing technology of fruit fermented beer; comprising the following steps: S1, selecting 8-9 ripe hard peaches, crushing the peaches to obtain peach particles after cleaning, mixing the peach particles with water at a mass ratio of 1:7-10, then connecting composite bacteria, enzymes, bacterial cellulose and blue algae for initial fermentation, and obtaining white peach liquid after squeezing, filtering and boiling; S2, crushing, saccharifying and boiling barley malt powder, then connecting beer yeast, and obtaining barley beer through fermentation treatment; adding the white peach liquid into the barley beer, and obtaining finished fermented beer through after-fermentation; the fermented beer has relatively strong fruit flavor aroma and is not prone to excessive fermentation of yeast, so that the content of aldehydes and fusel substances in the beer is controlled, and the taste and flavor of the finished beer are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of beer processing, more particularly, it relates to a processing technology of fruit fermented beer. BACKGROUND

[0002] Beer is a fermented wine made of malt and water as main raw materials, containing carbon dioxide and producing foam.

[0003] In the brewing process of beer, the following steps are generally experienced: crushing barley malt, saccharification, boiling, cooling, fermentation, the original wort concentration of ordinary beer is about 10-13 °P, the alcohol content is about 3%-6%, and the total acid is about 2%-3%, which is a relatively light and refreshing drink; therefore, the beer brewed by ordinary process has a single taste.

[0004] Fruit beer has a good fruit fragrance, and can balance the bitter taste of beer, so that women and young people can drink it appropriately, thereby widening the audience of beer; however, fruit generally contains high sugar content, and excessive sugar content can easily cause excessive fermentation of yeast, resulting in increased content of acetaldehyde and fusel, thereby affecting the taste and flavor of fruit beer.

[0005] White peaches have good fragrance and special taste, and are deeply loved by people, when white peaches are used to prepare fruit beer, if soft peaches are used, although the aroma is rich and can increase the fruit aroma of white peaches, the high sugar content of soft peaches can easily cause excessive fermentation of yeast, resulting in increased content of fusel and acetaldehyde, thereby affecting the taste of fruit beer; moreover, in the process of industrial production, fully ripe peaches are prone to rot, which affects the production of enterprises; if hard peaches are used, although they can be stored for a long time to ensure industrial production, the hard peaches are not fully ripe, and the fragrance is not rich enough, which can affect the fruit flavor of white peach beer.

[0006] Therefore, how to prepare a new fruit fermented beer with rich fruit aroma and without causing excessive fermentation of yeast, so as to control the content of aldehydes and fusel substances in beer and ensure the taste and flavor of the finished beer. SUMMARY

[0007] In order to prepare a new fruit fermented beer with good fruit aroma and without causing excessive fermentation of yeast, so as to control the content of aldehydes and fusel substances in beer and ensure the taste and flavor of the finished beer, the present application provides a processing technology of fruit fermented beer.

[0008] The processing technology of fruit fermented beer provided by the present application adopts the following technical scheme:

[0009] A processing technology of fruit fermented beer, comprising the following steps:

[0010] S1, selecting 8-9 mature hard peaches, washing and crushing to obtain peach particles, mixing the peach particles with water at a mass ratio of 1:7-10, then inoculating composite bacteria, enzymes, bacterial cellulose and blue algae for initial fermentation, after fermentation, squeezing, filtering and boiling to obtain white peach liquid; S2, crushing, saccharifying and boiling barley malt, then inoculating beer yeast for fermentation to obtain barley beer; adding white peach liquid to the barley beer for post-fermentation to obtain finished fermented beer.

[0011] By using the above technical scheme, the sugar content in the 8-9 mature hard peaches is only about 70%-80% of that in fully ripe peaches, so that the excessive fermentation of yeast in the fruit fermented beer is not easy to occur, and the content of acetaldehyde, fusel and other substances is controlled to ensure the taste and flavor of the fruit fermented beer.

[0012] The crushed peach particles contain white peach fruit aroma and rich nutrients under the fermentation of the composite bacteria, which enriches the taste and flavor of the beer; the enzymes, bacterial cellulose and blue algae added during the fermentation process decompose cellulose, fat, starch, protein and other substances in the hard peaches, ensure the fermentation effect of the composite bacteria, increase the content of amino acids and fatty acids, and the amino acids and fatty acids form esters in the oxygen environment, while the blue algae can produce oxygen through photosynthesis, further ensuring the content of ester substances in the hard peaches, and the ester substances in the fruit impart fruit aroma and fresh flavor, so that even the white peaches that have not yet fully matured still have high fruit aroma and sweet flavor after fermentation, at the same time, the high sugar content in the hard peaches does not affect beer fermentation, so that the fruit fermented beer has good fruit flavor aroma and is not easy to cause excessive fermentation of yeast, thereby controlling the content of aldehyde and ketone substances in the beer and ensuring the taste and flavor of the finished beer.

[0013] Preferably, the composite bacteria are composed of yeast, pectin-coated lactobacillus acidophilus and black aspergillus at a mass ratio of 1:0.1-0.3:0.1-0.2.

[0014] The yeast, the pectin-coated lactobacillus acidophilus and the aspergillus niger are cooperated, the yeast and the aspergillus niger grow and breed under the aerobic condition, the content of the bacteria is improved, the aspergillus niger metabolizes to produce the pectinase, the pectinase decomposes the pectin, the anaerobic lactobacillus acidophilus is exposed, the lactobacillus acidophilus metabolizes to produce the lactic acid, the acetic acid and the formic acid which affect the beer taste in the fermentation product are converted, the content of the organic acid produced in the eight-ninety percent mature hard peach is reduced, the fruitiness and the sweet degree of the white peach juice are improved; the yeast and the aspergillus niger have the conversion effect on the sugar, the alcohol produced by the metabolism and the ester formed by the citric acid and the malic acid in the eight-ninety percent mature hard peach, the white peach beer has the good fruitiness and the sweet flavor with the low sugar content of the white peach juice, the yeast does not easily over-ferment, the content of the aldehyde and the ketone in the beer is controlled, and the taste and the flavor of the finished beer are ensured.

[0015] Preferably, the bacterial cellulose is prepared from the bacterial cellulose silk, the calcium carbonate and the sodium carboxymethyl cellulose solution with a mass ratio of 1:0.1-0.2:0.1-0.2.

[0016] By adopting the above technical scheme, the bacterial cellulose silk and the calcium carbonate are cooperated, the advantages of the porous and large specific surface area of the bacterial cellulose silk are used to cooperate the viscosity of the sodium carboxymethyl cellulose solution, the calcium carbonate is easily loaded, the calcium carbonate can react with the organic acid to reduce the content of the organic acid such as the citric acid and the malic acid in the not fully mature hard peach, and the lactic acid produced by the metabolism of the compound bacteria and the remaining part of the organic acid can ensure the generation of the ester, so that the beer is not affected by the excessive acid in the beer due to the high content of the organic acid in the not fully mature hard peach.

[0017] Preferably, the enzyme is composed of the rhamnolipid-coated papain and the cellulase with a mass ratio of 1:0.5-1.

[0018] By adopting the above technical scheme, the rhamnolipid-coated papain and the cellulase are cooperated, the ester group in the rhamnolipid is used to contact with the fatty acid, the compound bacteria can gradually decompose the rhamnolipid, the papain is exposed after the decomposition of the rhamnolipid, the papain can decompose the fat to produce the fatty acid, the fatty acid can be oxidized to generate the ester, the fruitiness and the sweet degree of the white peach juice are enriched; and the decomposition of the protein and the cellulose in the hard peach by the papain and the cellulase can improve the content of the nutrient substance in the white peach juice, when the white peach juice is added into the barley beer, the finished fruit beer has the strong white peach flavor and the good taste.

[0019] Preferably, the initial fermentation in the S1 is specifically as follows:

[0020] After the access of the compound bacteria, the fermentation is carried out at 20-25℃ for 4-6 days to obtain a pre-fermentation liquid; the enzyme, bacterial cellulose and blue algae are added in the pre-fermentation liquid, and then the fermentation is carried out for 1-2 days, in the process, the sunlight is shined for 2-3 hours per day, and the stirring is carried out for 1-2 times per day, and each time for 5-10 minutes.

[0021] By adopting the above technical scheme, after the access of the compound bacteria, the fermentation temperature and time are limited, so that the sugar in the peaches is converted into ethanol, then the enzyme is added to promote the formation of ester from alcohol and acid, so that the peaches with 80-90% maturity still have high fruit aroma and sweet flavor, which is close to the fruit aroma of fully ripe peaches; then the enzyme, blue algae and bacterial cellulose are added, and a small amount of sunlight is used to make the blue algae produce continuous oxygen, and a small amount of stirring operation is used to make the oxygen in the external environment enter the inside, so as to ensure that the fatty acids and amino acids are oxidized with alcohol to generate ester, so that the white peach liquid has rich aroma, and the yeast is not easy to over-ferment to affect the taste of the fruit fermented beer.

[0022] In the early stage of the fermentation process of the access of the compound bacteria, the yeast can only produce ethanol by anaerobic fermentation, so during the fermentation process, stirring and sunlight shining operations cannot be accepted, and after 4-6 days of fermentation, in order to promote the generation of ester, the sunlight is shined for a short time and the stirring operation is limited, so that the white peach liquid has rich fruit aroma and sweet flavor, and the fruit aroma of the white peach juice obtained by the fermentation of fully ripe soft white peaches tends to be fully ripe.

[0023] Preferably, the S1 filtering step is as follows: the peach juice is separated by filtration, then the chitosan modified adsorption resin particles are added, and the liquid is filtered out after standing for 5-20 minutes.

[0024] By adopting the above technical scheme, the surface amino groups of the chitosan modified adsorption resin particles are used to complex the organic acids in the white peach juice, so as to reduce the content of the organic acids in the white peach juice which are not used to generate ester, so that the fruit fermented beer retains the white peach fruit aroma and sweet taste, and is not easy to affect the taste and flavor of the beer due to over-fermentation of the yeast.

[0025] Preferably, the beer yeast in S2 is prepared from beer yeast powder, papain and pectin solution with a mass ratio of 1:0.1-0.2:0.1-0.2.

[0026] By adopting the above technical scheme, the beer yeast powder, papain and pectin are matched, the uniform dispersion of the beer yeast powder can promote the uniform fermentation of barley, the decomposition of papain to protein and other substances can generate water-soluble polypeptides and small molecule amino acids, the content of protein in beer is controlled, so that the beer is not easy to produce turbidity and precipitation, the adsorption and connection of undecomposed protein, water-insoluble polypeptides and other substances in beer by pectin, and the partial consistency of pectin can further control the generation of beer turbidity problem, and ensure the clarification effect of beer.

[0027] Preferably, the pectin solution is a high-fat pectin solution with a mass fraction of 1-3%.

[0028] By adopting the above technical solution, high-fat pectin contains fatty acid groups, which can increase the content of esters in beer during the beer fermentation process, thereby improving the aroma and flavor of beer. Furthermore, by limiting the mass fraction of high-fat pectin, it can not only make the beer yeast powder and papain bind more evenly, ensuring that the protein in barley is decomposed and improving the beer fermentation efficiency, but also reduce the turbidity of beer and improve its clarity.

[0029] Preferably, the fermentation process in S2 is as follows: first, ferment at 5-10℃ for 5-8 days, and seal the container when the sugar content is measured to be 3.5-4°P. Then, ferment at a pressure of 0.1-0.15MPa and a temperature of 10-12℃ for 5-8 days.

[0030] By adopting the above technical solutions, the fermentation temperature and time are limited to ensure the fermentation effect of barley and control the content of higher alcohols and higher esters in beer. Too high a temperature can easily produce fusel alcohol flavors, affecting the taste of beer, while too low a temperature can easily affect the fermentation rate, thus limiting industrial production.

[0031] Preferably, the post-fermentation temperature is 0-2℃ and the time is 10-15 days.

[0032] By adopting the above technical solution and through post-fermentation, the flavors of white peach and beer are integrated, while the production of substances such as fusel alcohols is less likely. This gives the fermented beer a sweet and fruity aroma of white peach, ensuring the taste and flavor of the finished fruit-fermented beer.

[0033] In summary, this application has the following beneficial effects:

[0034] 1. Fully ripe white peaches have a sweetness of about 12-14%, and are characterized by their softness, high sweetness, and rich fruity aroma. However, hard peaches that are 80-90% ripe are not soft and have a lower sugar content than fully ripe peaches. This allows for control of the sugar content, preventing excessive fermentation of yeast under high sugar conditions. This, in turn, controls the content of acetaldehyde, fusel oils, and ketones, ensuring the taste and flavor of fruit-fermented beer.

[0035] 2. The enzymes, bacterial cellulose, and blue-green algae added during the fermentation process utilize the enzymes to decompose substances such as cellulose, fat, starch, and protein in the hard peach, increasing the content of amino acids and fatty acids. Amino acids and fatty acids form esters in an oxygen environment. The esters in the fruit give the fruit aroma and fresh flavor, so even white peaches that are not fully ripe still have a high fruity aroma and sweet flavor after fermentation.

[0036] 3、Full ripe peach shelf life is shorter, not suitable for industrial production, and eight or nine mature peach although the sweetness is lower than full ripe peach, but the organic acid content is higher than full ripe peach, so using chitosan adsorption resin particles, calcium carbonate and other substances to adsorb the remaining organic acid in white peach juice, reduce the organic acid content in fermented white peach juice, ensure the taste and clarity of the finished product fermented beer. DETAILED DESCRIPTION

[0037] The application will be further described in detail below in conjunction with examples.

[0038] Preparation example of pectin-coated lactobacillus acidophilus

[0039] The following raw materials are purchased from Shandong Jianyou Biological Engineering Co., Ltd., food grade; Lactobacillus acidophilus powder is purchased from Shenzhen Lovefu Biological Technology Co., Ltd., food grade; other raw materials and equipment used are ordinary market sales.

[0040] Preparation example 1: Pectin-coated lactobacillus acidophilus is prepared by the following method:

[0041] Mix high-fat pectin and white granulated sugar in a mass ratio of 1:2 and stir evenly, then add 80℃ water, mix and stir until all the high-fat pectin is dissolved, then cool to 50℃, to prepare a 2% high-fat pectin solution by mass fraction;

[0042] 1kg high-fat pectin solution is evenly sprayed on the surface of 1kg lactobacillus acidophilus, the spraying speed is 60g / min, and the stirring speed of lactobacillus acidophilus is 80r / min during the spraying process. Lactobacillus acidophilus is lactobacillus acidophilus powder, mix evenly, immediately dry, disperse, and prepare the finished product pectin-coated lactobacillus acidophilus, pass through a 300-mesh sieve.

[0043] Preparation example of bacterial cellulose

[0044] The following raw materials are ordinary market sales.

[0045] Preparation example 2: Bacterial cellulose is prepared by the following method:

[0046] Carboxymethyl cellulose sodium is stirred in water until all the carboxymethyl cellulose sodium is dissolved to prepare a 1% carboxymethyl cellulose sodium solution by mass fraction, 0.1kg carboxymethyl cellulose sodium solution is evenly sprayed on the surface of 1kg bacterial cellulose silk, the average length of the bacterial cellulose silk is 40μm, then 0.1kg calcium carbonate is added, the average particle size of the calcium carbonate is 10μm, the addition speed of the calcium carbonate is 30g / min, during the addition process of the calcium carbonate, the bacterial cellulose silk is stirred at a speed of 80r / min, mix evenly, dry, disperse, and prepare the finished product bacterial cellulose, pass through a 200-mesh sieve.

[0047] Preparation Example 3: The difference between this preparation example and Preparation Example 2 is that:

[0048] Spray 0.2 kg of sodium carboxymethyl cellulose solution evenly on the surface of 1 kg of bacterial cellulose filaments, then add 0.2 kg of calcium carbonate, the adding speed of calcium carbonate is 30 g / min, during the adding process of calcium carbonate, the bacterial cellulose filaments are stirred at a speed of 80 r / min, after mixing evenly, dry and disperse to obtain the finished product of bacterial cellulose.

[0049] Preparation Example of Rhamnolipid-coated Papain

[0050] The rhamnolipid in the following raw materials is food-grade L-rhamnolipid produced by Wuhan Huaxiang Kejebio Technology Co., Ltd., in liquid state; the papain is food-grade and purchased from Shandong Yatu Biotechnology Co., Ltd.

[0051] Preparation Example 4: The rhamnolipid-coated papain is prepared by the following method:

[0052] Spray 1 kg of rhamnolipid evenly on the surface of 1 kg of papain, dry and disperse to obtain the finished product, and pass through a 300-mesh sieve.

[0053] Preparation Example of Chitosan-modified Adsorption Resin Particles

[0054] The following raw materials are all ordinary commercial products.

[0055] Preparation Example 5: The chitosan-modified adsorption resin particles are prepared by the following method:

[0056] Spray 0.5 kg of chitosan solution evenly on the surface of 1 kg of adsorption resin particles, dry and disperse to obtain chitosan-modified adsorption resin particles; the average particle size of the adsorption resin particles is 80 μm, the chitosan solution is a chitosan acetic acid solution with a mass fraction of 1%, the degree of deacetylation of chitosan is 85%, and the concentration of acetic acid is 2%.

[0057] Preparation Example of Beer Yeast

[0058] The high-fat pectin in the following raw materials is food-grade and purchased from Shandong Jianyou Bioengineering Co., Ltd.; the beer yeast powder is beer yeast produced by Hubei Xingyan New Material Technology Co., Ltd.; the papain is food-grade and purchased from Shandong Yatu Biotechnology Co., Ltd.; other raw materials and equipment are all ordinary commercial products.

[0059] Preparation Example 6: The beer yeast is prepared by the following method:

[0060] Mix and stir the high-fat pectin and white granulated sugar at a mass ratio of 1:2 until they are evenly mixed, then add water at 80℃, mix and stir until the high-fat pectin is completely dissolved, then cool to 50℃ to obtain a pectin solution with a mass fraction of 1%;

[0061] 1 kg of beer yeast powder and 0.1 kg of papain are mixed and stirred uniformly, then 0.1 kg of pectin solution is uniformly sprayed, dried and dispersed to obtain the finished product.

[0062] Preparation Example 7: The difference between this preparation example and Preparation Example 6 is that:

[0063] High-fat pectin and white granulated sugar are mixed and stirred uniformly at a mass ratio of 1:2, then 80℃ water is added and stirred until the high-fat pectin is completely dissolved, then the temperature is lowered to 50℃ to obtain a pectin solution with a mass fraction of 3%;

[0064] 1 kg of beer yeast powder and 0.2 kg of papain are mixed and stirred uniformly, then 0.2 kg of pectin solution is uniformly sprayed, dried and dispersed to obtain the finished product.

[0065] Example

[0066] The following raw materials are all ordinary commercially available.

[0067] Example 1: A processing technology of fruit fermented beer:

[0068] S1, select 8-9 mature hard peaches, the sugar content of the hard peaches is 8-9%, wash and crush to obtain peach particles, mix the peach particles and water at a mass ratio of 1:8, then inoculate the complex bacteria and ferment at 20℃ for 4d to obtain a pre-fermentation liquid, the inoculation amount of the complex bacteria is 3*10 5 / mL, the complex bacteria are prepared by mixing yeast, pectin-coated Lactobacillus acidophilus prepared in Preparation Example 1 and Aspergillus niger at a mass ratio of 1:0.2:0.15, the Aspergillus niger is Aspergillus niger powder; then add enzymes, bacterial cellulose and blue algae to the pre-fermentation liquid, the enzyme addition amount is 40mg / L, the bacterial cellulose addition amount is 20mg / L, and the blue algae addition amount is 5mg / L, ferment at 20℃ for 2d, during which the liquid is exposed to sunlight for 3h every day, and stirred at 8am and 16pm every day for 5min each time, to complete the primary fermentation; the enzymes are prepared by mixing rhamnolipid-coated papain and cellulase prepared in Preparation Example 4 at a mass ratio of 1:0.5; the bacterial cellulose is prepared in Preparation Example 2, and the blue algae is food-grade spirulina powder; after fermentation, the peach juice is obtained by pressing and filtering, then chitosan-modified adsorption resin particles are added to the peach juice, the mass ratio of the peach juice to the chitosan-modified adsorption resin prepared in Preparation Example 5 is 100:2, the liquid is filtered again through a 400-mesh screen, and finally boiled for 10min and cooled to obtain white peach juice;

[0069] S2, the barley malt is crushed by a crusher to obtain malt powder; 100 L of water is added to a saccharifying kettle, heated to 50°C, and 32 kg of the malt powder is added to the saccharifying kettle for saccharification treatment; in the process, it is first treated at 50°C for 10 min, then heated to 60°C for 40 min, and finally heated to 70°C for 10 min; after the saccharification is completed, filtration is performed, then heating to 100°C is performed to boil, the wort concentration is 10°P to stop boiling, then clarification is performed for 30 min, and cooling to 10°C is performed to obtain wort; the beer yeast prepared in Preparation Example 6 and water are mixed and stirred uniformly at a mass ratio of 1:9, then introduced into the wort for fermentation, and the detected viable cell count is 2*10 6 / mL; then fermentation is performed, the sugar content is detected to be 3.5-3.8°P after fermentation at 8°C for 7 d, the tank is sealed, then fermentation is performed at 0.1 MPa and 12°C for 7 d to obtain barley beer; the white peach liquid is added to the barley beer at a mass ratio of 1:0.3, and post-fermentation is performed at 0°C for 12 d to obtain the finished fermented beer.

[0070] Example 2: The difference between this example and Example 1 is that:

[0071] S1, 8-9 mature hard peaches with a sugar content of 8-9% are selected, washed and crushed to obtain peach particles, then mixed with water at a mass ratio of 1:7, and then introduced into the composite bacteria for fermentation at 25°C for 3 d to obtain pre-fermented liquid, the introduction amount of the composite bacteria is 3*10 5 / mL, and the composite bacteria are prepared by mixing yeast, Lactobacillus acidophilus coated with pectin prepared in Preparation Example 1 and Aspergillus niger at a mass ratio of 1:0.1:0.1; then enzymes, bacterial cellulose and blue algae are added to the pre-fermented liquid for fermentation at 20°C for 1 d, the liquid is exposed to sunlight for 2 h every day during the 1 d, and stirring is performed once every day at 8 am for 10 min each time, and the primary fermentation is completed; the enzymes are prepared by mixing the rhamnolipid-coated papain and cellulase prepared in Preparation Example 4 at a mass ratio of 1:1; the bacterial cellulose is the bacterial cellulose prepared in Preparation Example 3, and the blue algae is food-grade spirulina powder; after fermentation, the peach juice is obtained by squeezing and filtering, chitosan-modified adsorption resin particles are added to the peach juice, and the mixture is left to stand for 5 min, the mass ratio of the peach juice to the chitosan-modified adsorption resin prepared in Preparation Example 5 is 100:2, the liquid is filtered again, the filter screen is 400 meshes, and finally boiling is performed for 10 min and the mixture is left to cool to obtain the white peach liquid;

[0072] S2, the beer yeast prepared in Preparation Example 6 and water are mixed and stirred uniformly at a mass ratio of 1:9, then introduced into the wort for fermentation, and the detected viable cell count is 2*10 6 / mL; then fermentation is carried out at 5 degrees Celsius for 8 days. The sugar content is measured to be 3.8-4°P and the container is sealed. Then fermentation is carried out at 0.15MPa and 10°C for 8 days to obtain barley beer. White peach extract is added to the barley beer at a mass ratio of 1:0.3 and fermented at 2°C for 10 days to obtain the finished fermented beer.

[0073] Example 3: The difference between this example and Example 1 is that:

[0074] S1. Select firm peaches that are 8-9 parts ripe (with a sugar content of 8-9%). Wash and crush them to obtain peach pieces. Mix the peach pieces with water at a mass ratio of 1:10, then inoculate with a compound bacteria and ferment at 20℃ for 5 days to obtain a pre-fermentation liquid. The inoculation amount of the compound bacteria is 3*10. 5 / mL, the compound bacteria were prepared by mixing yeast, pectin-coated Lactobacillus acidophilus prepared in Preparation Example 1 and Aspergillus niger in a mass ratio of 1:0.3:0.2; then enzymes, bacterial cellulose and cyanobacteria were added to the pre-fermentation liquid, and fermented at 20°C for 2 days. During these 2 days, the mixture was exposed to sunlight for 3 hours each day and stirred once at 8 am for 10 minutes each time to complete the initial fermentation; the enzymes were prepared by mixing rhamnolipid-coated papain and cellulase prepared in Preparation Example 4 in a mass ratio of 1:1; the bacterial cellulose was the bacterial cellulose prepared in Preparation Example 3, and the cyanobacteria were food-grade spirulina powder; after fermentation, the mixture was pressed and filtered to obtain peach juice, chitosan-modified adsorption resin particles were added to the peach juice, and the mixture was allowed to stand for 20 minutes. The mass ratio of peach juice to chitosan-modified adsorption resin prepared in Preparation Example 5 was 100:2. The liquid was filtered again through a 400-mesh sieve, and finally boiled for 10 minutes and cooled to obtain white peach liquid;

[0075] S2. The brewer's yeast prepared in Example 7 and water were mixed and stirred evenly at a mass ratio of 1:9, and then inoculated into the wort for fermentation. The viable count was 2*10⁻⁶. 6 / mL; then fermentation is carried out at 10 degrees Celsius for 5 days, and the sugar content is measured to be 3.8-4°P. The mixture is then sealed in a container and fermented for another 5 days at a pressure of 0.15MPa and a temperature of 12°C to obtain barley beer; white peach extract is added to the barley beer at a mass ratio of 1:0.3 and then fermented at 0°C for 15 days to obtain the finished fermented beer.

[0076] Example 4: The difference between this example and Example 1 is that:

[0077] No Aspergillus niger was added to the compound bacteria.

[0078] Example 5: The difference between this example and Example 1 is that:

[0079] The compound bacteria did not contain pectin-coated Lactobacillus acidophilus.

[0080] Example 6: The difference between this example and Example 1 is that:

[0081] The bacterial cellulose is commercially available bacterial cellulose.

[0082] Example 7: The difference between this example and Example 1 is that:

[0083] The equal mass of papain is replaced by rhamnolipid-coated papain in the enzyme.

[0084] Example 8: The difference between this example and Example 1 is that:

[0085] In S1, 8-9 ripe hard peaches with a sugar content of 8-9% are selected, washed and broken into peach particles, then mixed with water at a mass ratio of 1:8, and then inoculated with complex bacteria, enzymes, bacterial cellulose and blue algae, and fermented at 20°C for 7 days to complete the initial fermentation.

[0086] Example 9: The difference between this example and Example 1 is that:

[0087] In S1, the filtration step does not add chitosan-modified adsorption resin particles.

[0088] Example 10: The difference between this example and Example 1 is that:

[0089] The pectin solution is not added in the beer yeast.

[0090] Comparative Example

[0091] Comparative Example 1: The difference between this comparative example and Example 1 is that:

[0092] In S1, enzymes, bacterial cellulose and blue algae are not added.

[0093] Comparative Example 2: The difference between this comparative example and Example 1 is that:

[0094] In S1, fully ripe peaches with a sweetness of 13% are selected.

[0095] Comparative Example 3: The difference between this comparative example and Example 1 is that:

[0096] In S1, the same mass of litchi juice is used to replace white peach juice.

[0097] Specifically: Take fresh 10°P litchi juice, heat to 65°C for 27 min for sterilization, and cool to 12°C; mix water and yeast bacteria at a mass ratio of 1:10, stand for 18 min, and mix evenly; add the activated yeast liquid above to the litchi juice, and after inoculation, the active yeast number is about 3×10 5 / mL, fermentation for 7 days at 20℃, heating to 65℃ for 27 min to kill the yeast, cooling to 10±0.5℃, to obtain the litchi juice; the sweetness of the litchi is 18%.

[0098] Performance test

[0099] 1. Physicochemical property test

[0100] The fruit fermented beer was prepared by the preparation method of Example 1-10 and Comparative Example 1-3, respectively, and the appearance, sugar content, total acid and turbidity were detected according to GB / T4927, and the data were recorded.

[0101] 2. Fruit flavor property test

[0102] The fruit fermented beer was prepared by the preparation method of Example 1-10 and Comparative Example 1-3, respectively, and the fruit flavor was scored, and the tester was a national certified wine taster, 10 points for strong fruit flavor and 0 points for no fruit flavor.

[0103] Table 1. Performance test table (‘ / ’ in the table represents that the corresponding example or comparative example is not detected for the item, and there is no data result)

[0104]

[0105] 3. Flavor property test

[0106] The fruit fermented beer was prepared by the preparation method of Example 1-3 and Comparative Example 1-3, respectively, and the content of acetaldehyde, ethyl acetate, isoamyl acetate, ethyl hexanoate and fusel alcohol (fusel alcohol includes n-propanol, isobutyl alcohol and isoamyl alcohol) was detected according to GB / T4927, and the data were recorded.

[0107] Table 2. Performance test table (the unit of the detected data in the table below is mg / L, and ‘ / ’ represents that the corresponding comparative example is not detected for the item, and there is no data result)

[0108] Item Acetaldehyde Ethyl acetate Isoamyl acetate Ethyl hexanoate Fusel alcohol Example 1 8.78 22.58 1.54 0.16 25.12 Example 2 9.52 21.65 1.34 0.12 25.84 Example 3 8.64 22.79 1.60 0.18 25.03 Comparative Example 1 12.25 / / / 32.65 Comparative Example 2 15.48 / / / 38.47 Comparative Example 3 16.23 / / / 42.51

[0109] It can be seen from Example 1-3 in combination with Table 1 and 2 that the fruit fermented beer has low sugar content, low total acid content, low turbidity, good fruit flavor, and low content of acetaldehyde and fusel alcohol, so that the finished fruit fermented beer has good fruit flavor aroma and is not easy to cause excessive fermentation of yeast, the content of aldehydes and fusel alcohols in the beer is controlled, and the taste and flavor of the finished beer are ensured.

[0110] It can be seen from the combination of Example 4 and Examples 4-10 and in combination with Tables 1 and 2 that in Example 4, Aspergillus niger is not added in the composite bacteria, and in Example 5, Lactobacillus acidophilus coated with pectin is not added in the composite bacteria, compared with Example 1, the total acid of Example 4 and Example 5 is greater than that of Example 1, the fruit aroma score is lower than that of Example 1, and the turbidity of Example 5 is greater than that of Example 1; it is indicated that the addition of Aspergillus niger can decompose pectinase, then expose Lactobacillus acidophilus, utilize the generated lactic acid to transform acetic acid, formic acid and other substances, reduce the content of organic acids in unripe peaches, ensure the fruit aroma and sweet aroma of white peach juice, and thus ensure the fruit aroma flavor of beer; the addition of pectin can improve the clarity of white peach juice.

[0111] In Example 6, the bacterial cellulose is commercially available, compared with Example 1, the total acid of beer prepared in Example 6 is higher than that of Example 1, and the fruit aroma score is lower than that of Example 1; it is indicated that calcium carbonate can react with organic acids to reduce the content of excess organic acids such as citric acid and malic acid in unripe hard peaches, and lactic acid and part of the remaining organic acids metabolized by the composite bacteria can ensure the generation of ester substances, so that too much acid is not left in beer to affect the taste of beer.

[0112] In Example 7, the same mass of papain is used to replace rhamnolipid-coated papain in the enzyme, compared with Example 1, the fruit aroma score of beer prepared in Example 7 is lower than that of Example 1; it is indicated that the addition of rhamnolipid can not only promote the formation of esters from fatty acids, but also improve the fruit aroma flavor.

[0113] In Example 8, the composite bacteria, enzyme, bacterial cellulose and blue algae are mixed together, compared with Example 1, the total acid of beer prepared in Example 8 is greater than that of Example 1, and the fruit aroma score is lower than that of Example 1; it is indicated that batch addition and limited stirring means can ensure the presence of oxygen in the late fermentation stage, facilitate the oxidation of fatty acids and amino acids to generate esters, and thus improve the fruit aroma and sweet aroma of unripe peaches, so that the beer has the advantages of good flavor and no excessive fermentation.

[0114] In Example 9, no chitosan-modified adsorption resin particles are added in the filtration step, compared with Example 1, the total acid content of Example 9 is higher than that of Example 1, and the turbidity is greater than that of Example 1; it is indicated that chitosan-modified adsorption resin can adsorb organic acids, thereby reducing the content of organic acids in unripe peaches, and can adsorb undecomposed macromolecular proteins, thereby improving the clarity of beer.

[0115] In Example 10, no pectin solution is added in the beer yeast, compared with Example 1, the turbidity of beer prepared in Example 10 is greater than that of Example 1; it is indicated that pectin can bond undecomposed proteins, water-insoluble polypeptides and other substances, cooperate with the appropriate consistency of pectin, further control the generation of beer turbidity problem, and ensure the clarification effect of beer.

[0116] It can be seen from the combination of Example 1 and Comparative Examples 1-3 and in combination with Tables 1 and 2 that, compared with Example 1, the total acid of the beer prepared in Comparative Example 1 is greater than that of Example 1, the fruity flavor score is lower than that of Example 1, and the acetaldehyde and fusel content is higher than that of Example 1; it is shown that the addition of the enzyme, bacterial cellulose and blue algae can reduce the organic acid content in the unripe white peach and promote the generation of ester substances in the unripe peach, so as to ensure that the beer has the flavor of white peach and is not easy to over-ferment to produce too much aldehyde, fusel and other substances.

[0117] In Comparative Example 2, the peach is fully ripe, and compared with Example 1, the beer prepared in Comparative Example 2 has higher sweetness than Example 1, and the acetaldehyde and fusel content is higher than Example 1; it is shown that the fully ripe peach has higher sweetness, which easily affects the fermentation effect of the yeast, so that the beer is easy to be over-fermented by the yeast, thereby affecting the beer flavor and taste.

[0118] In Comparative Example 3, litchi is selected, and compared with Example 1, the beer prepared in Comparative Example 3 has higher sweetness than Example 1, and the acetaldehyde and fusel content is higher than Example 1; it is shown that the sugar content of litchi is about 16-20%, and the higher sugar content easily affects the fermentation effect of the yeast, so that the beer is easy to produce too much acetaldehyde and fusel, thereby affecting the beer flavor and taste.

[0119] The specific embodiments are merely an explanation of the present application, and are not a limitation of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A processing method for fruit-fermented beer, characterized in that, Includes the following steps: S1. Select 8-9 ripe peaches, wash and crush them to obtain peach granules. Mix the peach granules with water at a mass ratio of 1:7-10, inoculate with compound bacteria, and ferment at 20-25℃ for 3-5 days to obtain a pre-fermentation liquid. Add enzymes, bacterial cellulose and food-grade spirulina powder to the pre-fermentation liquid, and ferment for another 1-2 days. During the process, expose the liquid to sunlight for 2-3 hours per day and stir it 1-2 times a day for 5-10 minutes each time. After fermentation, press, filter and boil to obtain white peach liquid. The bacterial cellulose is prepared from bacterial cellulose filaments, calcium carbonate and sodium carboxymethyl cellulose solution at a mass ratio of 1:0.1-0.2:0.1-0.

2. S2. After crushing, saccharifying, and boiling barley malt, beer yeast is inoculated and fermented to obtain barley beer. White peach extract is added to the barley beer and it undergoes post-fermentation to obtain the finished fermented beer. The compound bacteria consist of yeast, pectin-coated Lactobacillus acidophilus, and Aspergillus niger in a mass ratio of 1:0.1-0.3:0.1-0.

2. The enzymes consist of rhamnolipid-coated papain and cellulase in a mass ratio of 1:0.5-1.

2. The processing technology for fruit-fermented beer according to claim 1, characterized in that, The S1 filtration step is as follows: filter and separate the peach juice, then add chitosan-modified adsorption resin particles, let stand for 5-20 minutes, and then filter out the liquid.

3. The processing technology for fruit-fermented beer according to claim 1, characterized in that, The brewer's yeast in S2 is prepared from brewer's yeast powder, papain and pectin solution in a mass ratio of 1:0.1-0.2:0.1-0.

2.

4. The processing technology for fruit-fermented beer according to claim 3, characterized in that, The pectin solution is a high-fat pectin solution with a mass fraction of 1-3%.

5. The processing technology for fruit-fermented beer according to claim 1, characterized in that, The fermentation process in S2 is as follows: first, ferment at 5-10℃ for 5-8 days, and seal the container when the sugar content is measured to be 3.5-4°P. Then, ferment at a pressure of 0.1-0.15MPa and a temperature of 10-12℃ for 5-8 days.

6. The processing technology for fruit-fermented beer according to claim 1, characterized in that, The post-fermentation temperature is 0-2℃, and the time is 10-15 days.

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