33 results about "Yeast metabolism" patented technology

The present invention relates to a process for preparing a nutritional, therapeutic or organoleptic product by growing non-recombinant yeast under aerobic conditions, in a medium that includes crude glycerol, as one possible carbon source to produce a yeast product. The yeast product can be processed to obtain such nutritional, therapeutic or organoleptic products as yeast paste, yeast metabolites, carbohydrates, proteins, functional proteins, nucleotides, yeast autolysates, yeast extract, yeast cell walls, beta-glucans, mannans or a product derived from a mineralized yeast product.

The invention relates to the field of feed, and in particular relates to a biological feed composition containing organic microelements, an application of the biological feed composition, a special sow compound premix, and a special sow feed. The biological feed composition comprises the organic microelements and yeast metabolism products, wherein the organic microelements comprise copper glycinate, ferrous fumarate, zinc lactate, manganese methionine, selenium yeast and chromium nicotinate. The yeast metabolism products in the biological feed composition can be used for promoting the developing of synergistic effects of the various microelements; the utilization rate of the microelements is increased, the premonition and the immunity of sows are improved, and the hormone metabolism related to the sow reproduction is adjusted, so that the fecundity of the sows is improved; the special sow feed containing the biological feed composition containing the yeast metabolism products and the organic microelements can obviously improve the estradiol level and the luteinizing hormone level of the sows, so that the fecundity of the sows is improved.

The present invention belongs to the field of microbial fermentation technology, and particularly to a micro ecological feed additive for regulating rumens and a preparation method thereof. The additive consists of metabolites and intracellular substances of yeast, and metabolites of aspergillus oryzae with a mass ratio of 15: 1, 20: 1 or 25: 1. Single strain industrial fermentation technology is used to produce a specific anti-stress metabolite composite, the method is stable in process, and effectively solves the defects that viable organism and enzyme preparations are easily inactivated and unstable, which greatly expands the application range of the additive, and is conducive to achieve the targeted product development of different animals and different physiological stages of the animals. The additive is not a viable organism preparation, but is the specific anti-stress metabolite composite produced by viable organisms after high density fermentation, and the additive is easy to store so that active ingredient activity cannot be decreased with prolonged storage time, which ensures active ingredient contents of the additive.

The invention discloses a production process for producing low-alcoholism blueberry wine through low-temperature fermentation. The process comprises steps of processing raw materials, adjusting components, conducting fermentation, conducting filtering, conducting fining, conducting freezing, conducting filtering, and conducting sterilizing and filtering. The production process provided by the invention, by controlling yeast metabolism, can reduce foreign flavor caused by the fermentation of by-products and can improve product taste. The wine body is pure and full in taste and good in palatability. By replacing a conventional thermal sterilization technology with a biological membrane filtering sterilization technology, the damage to an anthocyanin bioactive substance, a flavoring substance and a pigment in a sterilizing process is relieved, and natural nutrient ingredients in blueberries are reserved to the greatest extent. The preservation rate of an anthocyanin content, after fermentation, reaches 64% or above.

The invention discloses a production method of sparkling cider wine. The production method uses concentrated apple juice as a raw material, the apple juice is diluted or blended, then high-temperature pasteurization is performed to kill infectious microbes, then carbon dioxide produced by yeast metabolism is dissolved in wine liquid by adopting a natural pressure rising method in which a tank body is closed after normal pressure, low-temperature wine storage to make a yeast gradually settle after a fermentation liquor is mature preliminarily, and then under-pressure filtration, bottling and sterilization are performed. For balancing the sour taste, brought into the wine liquid, of organic acid in the apple juice, a sweetening agent is added during apple juice blending or before wine liquid filtration. Rapid fermentation of the cider wine is achieved by adopting the production method, the fermentation operation is convenient and rapid, and no sulfur dioxide residue is produced. A production test proves that the finished product sparkling cider wine has strong carbon dioxide mouth irritation, the full-bodied fermentation fragrance of the apple juice, moderate sourness and sweetness and relatively mellow taste and is suitable for industrial production.

The invention discloses a rice wine yeast metabolic engineering bacterium low in urea yield and a construction method thereof. The construction method includes: placing an encoding frame of a carbamido amidase gene DUR 1,2 in control of brewing yeast group forming high-expression thermoplastic polyimide 1 (TPI 1) transcription promoters and TPI 1 transcription terminators, and stably integrating TPI 1p-DUR1,2-TPI1t gene cassette in a bacterial strain rice wine yeast bacterial strain genome through homologous recombination to obtain the rice wine yeast metabolic engineering bacterium. The rice wine yeast metabolic engineering bacterium has the remarkable advantage of being low in urea production level, rice wine produced through fermentation of the rice wine yeast metabolic engineering bacterium is low in ethyl cellulose (EC) content and keeps flavor basically unchanged, and therefore the rice wine yeast metabolic engineering bacterium has wide application prospect.

The invention discloses industrial rice wine yeast metabolic engineering bacteria with low-yield urea. The building method of the engineering bacteria comprises the following steps: building URA3 gene knockout component, respectively transforming a-type and alpha-type haploid rice wine yeasts, so as to obtain a uracil defect type strain; building a strong promoter containing PGK1p and a high-expression component of a URA3 gene; respectively transforming the a-type and alpha-type haploid rice wine yeasts; integrating into a strain genome by homologous recombination; inserting the PGK1p strong promoter before an initiation codon of a DUR1,2 gene to obtain a prototrophic haploid engineering strain for high expression of the DUR1,2 gene; fusing into diploid again, so as to obtain the industrial rice wine yeast metabolic engineering bacteria with low-yield urea. The engineering bacteria disclosed by the invention are prototrophic, the growth and fermentation abilities are very nearly the same as those of a parent strain, the content of urea and EC in a fermentation liquor can be obviously reduced, and no exogenous gene is led in. Therefore, the industrial rice wine yeast metabolic engineering bacteria are high in biosecurity and have good industrial application prospects.

The present invention relates to a process for preparing a nutritional, therapeutic o organoleptic product by growing non-recombinant yeast under aerobic conditions, in medium that includes crude glycerol, as one possible carbon source to produce a yeas product. The yeast product can be processed to obtain such nutritional, therapeutic o organoleptic products as yeast paste, yeast metabolites, carbohydrates, proteins functional proteins, nucleotides, yeast autolysates, yeast extract, yeast cell walls, beta glucans, mannans or a product derived from a mineralized yeast product.

The invention aims to provide mulberry soy sauce which has the nutrient components of mulberries, has the color of purple red brown, has gloss, has thick soy sauce fragrance, ester fragrance and thickmulberry fragrance, and is delicious and mellow in taste, fresh, sweet and palatable, slight in salty taste, unique in flavor and rich in nutrition, and a new variety is provided for the soy sauce family. Compared with conventional high-salt diluted soy sauce, the mulberry soy sauce has three bacteria of aspergillus oryzae, aspergillus niger and monascus, so that enzyme systems are enriched, andthe protease activity, the saccharifying enzyme activity and the monascorubin value are increased; in high-salt fermentation, saccharomyces rouxii and saccharomyces cerevisiae LM001 of an appropriateratio are added, gentle brewing at 30 DEG C or less is implemented, the fermentation and fragrance generation capability of the saccharomycetes can be effectively improved, and the fermentation time can be shortened. Organic acids generated when lactobacillus FJ001 is fermented and alcohols generated from yeast metabolism are compounded to generate esters, and thus the decorous feeling of the taste of the soy sauce is further improved.

The invention discloses a yeast strain promoter with weakened regulation intensity and application thereof. The invention specifically discloses a DNA molecule, and the DNA molecule is a recombinant promoter with reduced or weakened regulation intensity obtained by integrating a heterologous cis-acting regulatory element with a repression effect and a yeast strain inner source endogenous promoter. According to the invention, the intensity of the yeast strain promoter can be effectively reduced by integrating the marO sequence, the gene expression level is reduced from the transcriptional level, and a new tool is provided for reducing the metabolic flux of a branch way, a decomposition way or a derivative way in yeast metabolic engineering. The metabolic flux from squalene to sterol can be effectively reduced by applying the promoter weakening strategy to weakening of a yeast squalene derivation path. The yeast strain for producing squalene, provided by the invention, can realize efficient accumulation of squalene, reduce the fermentation cost and simplify the fermentation process under the condition of not adding additional enzyme inhibitor terbinafine or other effectors, with a very good industrial application prospect.

A mixture of the hard resins, lipids and waxes obtained by solvent extraction of hops can be effectively utilized in brewing processes to suppress foaming. The mixture is typically the residue obtained by extraction of hops with liquid carbon dioxide, or other solvents, followed by extraction of alpha acids, beta acids and essential oils from the whole hop extract. The mixture of natural products is at least as effective as silicone antifoams, and has been shown to improve fermentation rates because the presence of hop lipids has a positive effect on yeast metabolism.

The invention relates to a method for breeding a yeast, with which the production of sulfurous acid which is important for maintaining freshness during brewing is increased and the production of hydrogen sulfide which is one of the causes for nasty odor is not increased based on analytical results of yeast metabolites and gene expression levels, and a method for producing a high quality liquor using the yeast. That is, the invention relates to a method for breeding a yeast in which the production amount of hydrogen sulfide is not increased compared with its parent cell line and the production amount of sulfurous acid is increased by increasing the metabolic flux in the synthetic pathway from sulfate ions to hydrogen sulfide and increasing the amount of synthesized homocysteine from O-acetylhomoserine in the hydrogen sulfide and sulfurous acid production pathways of yeast, and a method for producing a liquor using the yeast.

The invention discloses a brewing method of kiwi fruit wine. The brewing method comprises the following steps: fruit selection; pulping; enzymolysis; sugar regulation; fermentation; filtration and ageing to finish fermentation. The brewing method is characterized in that a certain amount of sea-buckthorn seed pulp is added into fermenting slurry, production and reproduction of yeast in a fermenting liquid in an anaerobic condition through unsaturated fatty acid in the sea-buckthorn seed pulp to shorten the fermenting time, and meanwhile, the unsaturated fatty acid promotes the yeasts to metabolize to generate more aromatic metabolic products, so that the fragrance of the fruit wine is adjusted, and the quality of the wine fruit is improved. In addition, impurities of the fruit wine are separated through filtration. Various nutrients in the kiwi fruits and sea-buckthorn seeds will be remained in a fermented fruit wine product effectively, so that the fruit wine keeps relatively high nutritional value.

The invention relates to the field of fruit wine processing, in particular to a preparation method of mulberry wine. In the process of brewing the mulberry wine, through production of a proper amountof higher alcohol, increase in the coordination of the fruit wine is facilitated and the fruit wine is endowed with a mellow and full mouth feel; the excessive higher alcohol brings an unpleasant eviltaste to the fruit wine, so that drunkenness is easily caused after a user drinks the fruit wine too much; a fermentation solution of the fruit wine is rich in nutrient, so that the yeast metabolismis vigorous and the reproduction speed is high, and thus the higher alcohol massively accumulates; a strain screened by the preparation method provided by the invention has the characteristic of low-yield higher alcohol through the coordination with the fermentation solution; through addition of a proper amount of a nitrogen source, during yeast fermentation, use of nitrogen in produced amino acidfor producing the higher alcohol due to lack of the nitrogen source is prevented; and production of a large amount of amino acid feeds back and inhibits the activity of synthetase, and the intensityof a catabolic pathway is increased, so that the production amount of the higher alcohol is inhibited.

The invention discloses a yeast promoter with weakened regulation strength and application thereof. The invention specifically discloses a DNA molecule. The DNA molecule is a recombinant promoter with a reduced or weakened regulatory strength obtained by integrating a heterologous cis-regulatory element with a repressive effect on a yeast endogenous promoter. The invention can effectively down-regulate the strength of yeast promoter by integrating the marO sequence, reduce the gene expression level from the transcription level, and provide a new tool for down-regulating the metabolic flux of branch pathway, decomposition pathway or derivative pathway in yeast metabolic engineering transformation. Applying this promoter attenuation strategy to the attenuation of the yeast squalene-derived pathway can effectively reduce the metabolic flux from squalene to sterols. The squalene-producing yeast strain provided by the present invention can realize high-efficiency accumulation of squalene without additional addition of enzyme inhibitor terbinafine or other effectors, reduce fermentation cost, simplify fermentation process, and have great advantages. Good prospects for industrial application.

The invention relates to calophyllum inophyllum fruit beer and a brewing method thereof. The calophyllum inophyllum fruit beer comprises the following raw materials in percentage by weight: 33 to 59 percent of Pilsner malt, 1 to 2 percent of burnt malt, 30 to 45 percent of wheat malt and 10 to 20 percent of calophyllum inophyllum fruit juice. The adding time of the calophyllum inophyllum fruit juice in the beer brewing process of the invention is during boiling, before main fermentation and before can sealing. The calophyllum inophyllum fruit juice is added during the boiling, and the high temperature is favorable for leaching of micromolecular nutrient substances. Through combination with the calophyllum inophyllum fruit juice added before the main fermentation, sufficient nutrient substances are provided for production of special flavor substances of the calophyllum inophyllum fruit through yeast metabolism in the subsequent process; and in addition, through the addition of the calophyllum inophyllum fruit juice before the can sealing, the original flavor of the calophyllum inophyllum fruit can be effectively maintained. Therefore, through the addition of the calophyllum inophyllum fruit juice in three times, the flavor substances and the nutrient substances of the calophyllum inophyllum fruits are effectively maintained.

The invention relates to a processing method of rabbit manure biological fermentation feed. The processing method is characterized by comprising the following steps: preparing 100 kg of a nutrient solution from dried rabbit manure powder, 3.2 kg of brown sugar, 2.5 kg of calcium lactate, 0.15 kg of magnesium sulfate, 10 kg of wort, 10 kg of soybean milk, 10 kg of carrot juice, 10 kg of potato juice and the balance of water, mixing at the ratio of 1:(1.5-2.5), sterilizing, fermenting, drying, smashing, screening and the like to obtain the rabbit manure biological fermentation feed, wherein the fermentation is performed by adding a saccharomyces fermentation agent into a culture medium with the weight ratio of the culture medium to the saccharomyces fermentation agent to be 1:(0.035-0.065). The nutrient solution replaces water to adjust the water content of a cultured material, and the utilization of the nutrient solution not only can provide more enough nutrition for the saccharomyces fermentation agent to enable the saccharomyces to be vigorous in metabolism and increased in propagating quantity to form more mycoproteins, but also can improve the nutrient substances of the whole fermented culture material. The product is high in organic matter transformation rate, high in protein content, and is a good protein feed source, and the crude protein content is 32-36%.

The present invention relates to a preparation method of passion fruit sparkling apple wine. The method comprises the following steps of (1) preparing passion fruit juice; (2) adding water to the passion fruit juice, performing boiling, and adding apple juice and yeast nutritive salt, thereby preparing passion fruit and apple mixed fermentation liquid; and (3) fermenting the mixed fermentation liquid by using fruit wine yeasts until the sugar degree is 7-9.5%, adding the passion fruit juice, and performing freezing, storing and filtering to prepare the passion fruit sparkling apple wine. According to the method, the passion fruit is added on the basis of taking apples as raw materials, so that the finished fruit wine has rich and delicious fruit aromas, the wine body, the foam property andthe non-biological stability of the sparkling apple wine are improved, and the mouth feel and the fruit aromas of the sparkling apple wine are layered and stereoscopic; and the finished sparkling apple wine has the typical flavor characteristics of champagne, ester aroma generated by yeast metabolism and alcohol, apple aroma and passion fruit aroma in the fruit wine are mutually supplementary, the mouth feel is rich, and the fruit wine has a strong sense of layering.

The invention discloses a brewing method of mango wine. The brewing method includes steps: fruit selection, pulping, enzymolysis, sugar blending, fermentation, filtering and aging. The brewing methodis characterized in that a certain amount of sea-buckthorn seed meal is added into fermentation pulp, production and multiplication of yeast in the fermentation pulp under anaerobic conditions are promoted to short fermentation time through unsaturated fatty acid in the sea-buckthorn seed meal, and the unsaturated fatty acid promotes yeast metabolism to generate more aromatic metabolites so as toadjust aroma of the mango wine and improve quality of the same. In addition, filtering is adopted to separate impurities, and various nutritional substances in mango and the sea-buckthorn seed meal can be effectively retaining in a fermented mango wine finished product, so that the mango wine maintains high nutritional value.

The object of the present invention is to provide a kind of mulberry soy sauce. The mulberry soy sauce provided by the present invention has the nutritional components of mulberry, and the color is purple-reddish brown, shiny, has a relatively strong sauce aroma and ester aroma and a relatively strong mulberry aroma, and is delicious. It is full-bodied, sweet and palatable, less salty, unique in style and rich in nutrition, adding a new variety to the soy sauce family. Compared with the traditional high-salt dilute soy sauce, the koji uses three strains of Aspergillus oryzae, Aspergillus niger and Monascus, which enriches the enzyme system and improves the activity of koji-making protease, glucoamylase activity and red koji pigment value; when high-salt fermentation Adding an appropriate proportion of Saccharomyces rouxii and Saccharomyces cerevisiae LML001, brewing at 30°C, can effectively improve the fermentation and aroma production ability of the yeast, and shorten the fermentation time. The organic acid produced by the fermentation of Lactobacillus FJ001 and the alcohol produced by yeast metabolism are combined to form an ester, which further gives the soy sauce a thick taste.

The present invention discloses an animal feed yeast body protein and a preparation method thereof; the animal feed yeast body protein comprises candida utilis, candida tropicalis, torulopsis torulopsis, saccharomyces cerevisiae, a mixed additive, and water added to 1g as a supporter; wherein in more than 1800 strains of the three types of strains, a strain biochemical experiment and a strain symbiosis experiment are carried out, thereby selecting the microorganisms and preparing a yeast suspension. According to the present invention, the variety, the digestive tract microflora and the physiological digestion characteristics of animals are fully paid attention to, and the rich functional factors can improve the gastrointestinal function and the immune function of the animals, so that the animal feed yeast body protein is rich in B vitamins, organic trace elements, enzymes, small peptides, organic acids and other various yeast metabolites. The product can improve the digestion utilization rate of the feed, improve the production performance and reduce the production cost. Therefore, the feed digestion and utilization rate is increased, the disease resistance of the organism is enhanced, and the mycoprotein is high-quality mycoprotein which is very suitable for pigs, poultry, cattle and aquatic animals.

The invention relates to the field of fermentation engineering and feed raw material and particularly discloses disc solid aerobic fermentation soybean meal as well as a preparation method and application thereof. The preparation method comprises the following steps: raw material moistening with water, cooking, cooling, inoculating, carrying out disc fermentation, carrying out low-temperature drying, crushing, weighing and packaging, wherein the inoculation and fermentation comprises first-stage aspergillus oryzae solid-state culture and fermentation and second-stage saccharomyces cerevisiae culture and fermentation; the disc is used as a fermentation container, so that intelligent regulation and mechanical continuous production are realized; the obtained fermented soybean meal is stable and reliable in quality, rich in digestive enzymes and yeast metabolites, high in crude protein and acid-soluble protein content, low in anti-nutritional factor and good in palatability and food calling effect, and the in-vitro bionic digestibility is larger than or equal to 80%, the antinutritional factor is low, and the soybean meal has good palatability and food calling effect; the fermented soybean meal is used in animal breeding and can significantly improve digestion and absorption of animals to feed nutrients, improve growth performance, enhance immunity, reduce a feed-weight ratio, improve unit capacity and bring economic benefits to farmers.

The invention relates to a preparation method for yeast culture, belongs to the field of yeast culture, and aims to solve the problem that infectious microbes in a yeast culture preparation process are more. The preparation method for yeast culture comprises the steps of culture enlarged cultivation, liquid fermentation, solid fermentation, finished product obtaining and the like, wherein a solidculture medium is prepared from the following raw materials: stalks, corn powder, bran, cross-linked sephadex, 1-(2-(beta-d-pyranglucoxy)-4,6-dihydroxy phenyl)-3-(4-hydroxyl phenyl)-acetone, D-2,3,5,6-tetrahydroxy-2-hexenic acid-gamma-lactone. The preparation method greatly reduces pollution of infectious microbes, and cell content obtained by wall breaking of yeast cells, cell walls, a yeast metabolic end product and a culture medium in the prepared yeast culture define a bioactive feed additive.

The invention discloses a production method of sparkling cider wine. The production method uses concentrated apple juice as a raw material, the apple juice is diluted or blended, then high-temperature pasteurization is performed to kill infectious microbes, then carbon dioxide produced by yeast metabolism is dissolved in wine liquid by adopting a natural pressure rising method in which a tank body is closed after normal pressure, low-temperature wine storage to make a yeast gradually settle after a fermentation liquor is mature preliminarily, and then under-pressure filtration, bottling and sterilization are performed. For balancing the sour taste, brought into the wine liquid, of organic acid in the apple juice, a sweetening agent is added during apple juice blending or before wine liquid filtration. Rapid fermentation of the cider wine is achieved by adopting the production method, the fermentation operation is convenient and rapid, and no sulfur dioxide residue is produced. A production test proves that the finished product sparkling cider wine has strong carbon dioxide mouth irritation, the full-bodied fermentation fragrance of the apple juice, moderate sourness and sweetness and relatively mellow taste and is suitable for industrial production.

The invention relates to the technical field of microorganisms, in particular relates to an anti-inflammatory effect of oxidative stress yeast metabolite and application of the oxidative stress yeast metabolite in preparation of anti-inflammatory products. The invention provides a preparation method of the oxidative stress yeast metabolite; an experiment shows that the yeast metabolite can inhibit expression of COX-2 and activation of an NF-kappaB signal channel and can play effects of inhibiting inflammatory cell infiltration, inhibiting increment of nuclear-cytoplasmic ratio of cells, and inhibiting epidermal keratinization and / or reducing swelling degree so as to prove that the yeast metabolite has an anti-inflammatory effect, can be applied to related fields of drugs, cosmetics, health care products, food and the like, and can be made into dosage forms such as tablets, capsules, cream and liquid.

The invention discloses a method for manufacturing brown rice wine with red rice yeast. The method includes steps of (1), preparing raw materials including, by weight, 44.1% of brown rice, 44.1% of purified water and 11.8% of red yeast rice; (2), soaking the brown rice for at least 8 hours; (3), draining obtained brown rice and then steaming the brown rice until rice is cooked but not mushy; (4),cooling obtained brown rice by means of spreading until the temperature of the brown rice reaches 30 DEG C, adding the red yeast rice into the brown rice, mixing the brown rice, the red yeast rice andthe purified water with one another, and uniformly stirring the brown rice, the red yeast rice and the purified water to carry out primary fermentation; (5), carrying out primary fermentation at theprimary fermentation temperature higher than 20 DEG C; (6), sealing wine jar openings after primary fermentation is completed and carrying out further fermentation for 28-32 days; (7), filtering wineafter fermentation is completed, heating and disinfecting the wine and clarifying the disinfected wine to obtain the brown rice wine. The method has the advantages that processes for manufacturing thebrown rice wine are simple; diversified active substances can be dissolved in wine with the red rice yeast in brown rice leaven and red rice yeast metabolism procedures, and accordingly nutritional and healthcare functions of the brown rice wine can be improved; the wine with the red rice yeast is pink and bright, wine bodies have outstanding aroma, and the brown rice wine is sweet, sour and palatable and is excellent in color, flavor and functional performance.

The invention discloses a salmonella-pollution-resistant compound feed for laying hens. The salmonella-pollution-resistant compound feed comprises the following components: corn, soybean meal, biological fermentation raw materials, chili powder, rice bran, soybean oil, yeast metabolites, lactobacillus plantarum, mountain flour, calcium hydrophosphate, table salt, methionine, lysine, choline chloride with the purity of 60%, baking soda, phytase, composite vitamins and trace elements. According to the feed disclosed by the invention, three raw materials, namely the biological fermentation raw materials, the yeast metabolites and the lactobacillus plantarum, are combined to be used as an additive for cooperation, so that the feed can remarkably inhibit the growth of salmonella, it is ensuredthat salmonella detection in the feed is negative, and a finished feed product is not polluted in a transfer process; meanwhile, the feed laying hens can be prevented from being polluted by salmonellaunder the condition that a heating process is not needed and formaldehyde additives and organic acids are not additionally added into the feed, and the antibacterial effect on salmonella and escherichia coli is obvious.

The invention discloses a method for detecting the metabolic activity of yeast in the beer fermentation process, comprising the following steps: after starving the yeast collected in the fermentation liquid, adjusting the induced initial pH of the bacteria suspension, adding glucose to induce the outflow of yeast H+, and calculating Yeast maximum H+ efflux rate, and it is used to characterize the metabolic activity of yeast. The method of the invention can not only accurately reflect the difference in the activity of yeast strains, but also can be used to evaluate the metabolic activity of yeast in the fermentation process, and the result is accurate and repeatable. The invention can be used to quickly analyze the metabolic status and fermentation performance of yeast in the beer fermentation process.