241 results about "Carbohydrase" patented technology

The invention discloses a composite microbial enzyme preparation and a preparation method thereof, and belongs to the technical field of bioplastic degradation. The enzyme preparation is synergistically constructed through a temperature-sensitive MOFs / Schiff base network composite carrier and black phosphorus quantum dots, FeO (at) ZIF-8 is taken as a core, and PNIPAM is grafted on the surface to form temperature-responsive MOFs; constructing a three-dimensional network carrier through Schiff base crosslinking of the CMC and the CNF; the complex enzyme is loaded on MOFs pore channels and then is embedded in a carrier network together with the black phosphorus quantum dots. The temperature-sensitive MOFs open pore channels to release enzyme when the compost is heated, and the Schiff base network dissociates secondary released enzyme under an acidic condition; the black phosphorus quantum dots promote enzyme activity and strengthen carrier response through a photothermal effect; the compound enzyme contains cutinase, alkaline lipase, neutral lipase, alpha-amylase, saccharifying enzyme, cellulase, laccase and protease, and can synergistically degrade PLA, PBAT and starch-based plastic. According to the invention, dual environment response controlled release, photo-thermal synergistic catalysis and synergistic degradation of the enzyme preparation are realized, and the plastic degradation period is shortened under the composting condition.

The invention relates to the technical field of microorganisms, in particular to an Aspergillus oryzae ZA307 strain and application of the Aspergillus oryzae ZA307 strain. The aspergillus oryzae ZA307 high-yield protease and aminopeptidase provided by the invention cooperate with aspergillus oryzae Huniang 3.042 for starter propagation, so that the activity of the protease, aminopeptidase, saccharifying enzyme and amylase of a starter material can be remarkably improved, and furthermore, the content of ammonia nitrogen and total nitrogen and the variety and content of volatile flavor substances in a product are remarkably improved. The soy sauce or soybean paste prepared and fermented by double-strain starter propagation is obviously improved in the aspects of sauce fragrance, ester fragrance, delicate flavor and harmonious taste, and the quality of the product is comprehensively improved.

The method for preparing D-mannose through catalysis can effectively reduce the amount of by-products glucose and fructose, and greatly improves the conversion rate of D-mannose. Specifically, engineering bacteria for expressing isoamylase genes and engineering bacteria for expressing alpha-glucan phosphorylase genes, glucophosphate mutase genes, difunctional enzyme glucophosphate isomerase / mannose 6-phosphate isomerase genes and mannose 6-phosphate phosphatase genes are utilized, starch or starch derivatives are used as substrates, and the starch or starch derivatives are used as substrates. A phosphate buffer solution and Mg < 2 + > are added, a preliminary catalysis system is constructed, after the reaction is completed, an incompletely-reacted substrate and maltodisaccharide exist in the reaction system, the incompletely-reacted substrate and maltodisaccharide can be hydrolyzed into glucose by glucoamylase, and the polyphosphoglucokinase can be used for catalyzing the reaction of the polyphosphoglucokinase under the assistance of sodium hexametaphosphate. All glucose is converted into phosphorylated glucose, then D-mannose is generated, and by-products in a system are removed while the yield is increased.

The invention discloses a preparation method of V-shaped adsorptive starch, and belongs to the technical field of starch modification. The preparation method comprises the following steps: firstly, carrying out high-temperature alcohol-water heat treatment to obtain V-type starch with a V-type single-spiral structure, expanded and loose particles, a large amount of exposed hydroxyl groups and relatively high reaction activity; pullulanase which has a poor enzymolysis effect on original starch and is not applied to enzymolysis of the V-type starch is subsequently adopted for enzymolysis, due to the fact that pullulanase has different enzymolysis characteristics from common saccharifying enzyme and alpha-amylase, short-chain dextrin formed during enzymolysis can be combined with ethyl alcohol to form a V-type compound with an adsorption effect, the V-type compound can be precipitated by the ethyl alcohol, and then the V-type compound can be separated and purified. The utilization rate of enzymolysis byproducts is improved, so that the yield of final products can be improved.

The invention discloses a preparation method of a whole-bean rumex hanus nutrient plant enzyme, which comprises the following steps: S1, taking soybeans, and preparing whole-bean minced soybean; taking rumex hanus to prepare rumex hanus whole pulp; taking grains, and preparing whole grain pulp paste; taking fruits and vegetables, and preparing fruit and vegetable puree; s2, mixing the whole-bean minced soybean, the rumex hanus whole pulp, the whole-grain minced pulp and the fruit and vegetable primary pulp obtained in the step S1 to obtain whole-bean rumex hanus nutrient plant enzyme primary pulp, and then sequentially performing enzymolysis by combining cellulase with pectinase, amylase, saccharifying enzyme and protease; and S3, taking the whole-bean rumex hanus nutrient plant enzyme primary pulp subjected to enzymolysis in the step S2, performing anaerobic fermentation by using saccharomycetes and / or distiller's yeast under the negative pressure condition of-0.1 to-0.06 MPa, and filtering to obtain the whole-bean rumex hanus nutrient plant enzyme. The invention further provides the whole-bean rumex hanus nutrient plant enzyme. According to the technical scheme, the defects of traditional bean products, rumex hanus food and edible plant enzymes can be overcome.

The preparation method comprises the following steps: degreasing polygonatum cyrtonema leaf superfine powder, sequentially carrying out ultrasonic-assisted enzymolysis treatment on cellulase, xylanase, high-temperature-resistant alpha-amylase, papain and saccharifying enzyme, and carrying out alcohol precipitation, dialysis and vacuum freeze drying treatment to obtain the polygonatum cyrtonema leaf polysaccharide. The polygonatum cyrtonema leaf enzyme extraction crude polysaccharide is obtained; and separating the enzyme-extracted crude polysaccharide through a cellulose column, and purifying through a sephadex column to obtain the polygonatum cyrtonema leaf enzyme-extracted polysaccharide. Polysaccharide in polygonatum cyrtonema leaves is extracted through ultrasonic-assisted compound enzyme, single pure polysaccharide is obtained through alcohol precipitation, dialysis, cellulose column chromatography and gel column chromatography, and the purity can reach 99.86%; the obtained enzyme extraction polysaccharide has good anti-cancer activity, can significantly inhibit proliferation of breast cancer cells and colorectal cancer cells, has the characteristics of good biocompatibility, strong specificity, low toxic and side effects and the like, and has wide application prospects.

The invention relates to the technical field of wine brewing, and discloses a bamboo leaf powder added distilled liquor and a preparation method thereof, and the distilled liquor is prepared from 75-85 parts of grain powder and 15-25 parts of enzyme-deactivated bamboo leaf powder. The preparation method comprises the following steps: mixing the raw materials to obtain a dry mixture; adding a compound enzyme preparation containing cellulase and pectinase, preserving heat at 50-55 DEG C, performing enzymolysis and moistening, destroying a fiber structure and converting fermentable sugar; cooking the moistened material, and adding a saccharifying enzyme for saccharifying; primary fermentation is performed at 28-32 DEG C, and then secondary fermentation is performed at 22-25 DEG C; during distillation, foreshot with the expected wine yield of 1.5%-2.0% is intercepted and abandoned to remove methanol, fractions with the volume of 50% or above are collected to obtain raw wine, and the wine is obtained through ageing. The raw material utilization rate and the wine yield are improved through enzymolysis, the methanol content is controlled through temperature-variable fermentation and precise cut distillation, the raw and green taste of bamboo leaves is eliminated, and the finished wine has the unique composite style of bamboo fragrance and grain fragrance.

The invention discloses a method for brewing high-quality antioxidant Luzhou-flavor liquor in a semi-solid state. The method comprises the following steps: separating glutinous sorghum serving as a wine brewing raw material into sorghum rice and sorghum peel through rice milling, recovering residual starch in the sorghum peel by adopting alpha-amylase and saccharifying enzyme, releasing different tannins by adopting cellulase, and depolymerizing tannin dissolved in the sorghum peel and a solution by adopting laccase to release tannin with different structures, so as to obtain tannin enzymatic hydrolysate; the enzymatic hydrolysate is added into the steamed peeled sorghum rice according to a certain proportion, so that the thermal destructive effect of the steamed material on tannin in the sorghum rice is avoided; and adding yeast for making the white spirit in a semi-solid state to obtain the white spirit which has the antioxidant activity exceeding 80% compared with that of the existing white spirit and meets the national standard of semi-solid Luzhou-flavor white spirit. Compared with the traditional baijiu brewed by steaming sorghum, the total ester content of the baijiu brewed by adding the tannin enzymatic hydrolysate is increased by 87.50-102.27%, the free radical scavenging rate of DPPH is increased by 134.16-158.71%, and the content of guaiacol substances (4-ethyl guaiacol and guaiacol) is increased by 160.69-166.90%.

The invention discloses a germinated brown rice fermentation product filtrate as well as a preparation method and application thereof, and the preparation method comprises the following steps: S1, adjusting the pH value of a CaCl2 solution with glutamic acid to obtain a CaCl2 germination accelerating solution, immersing disinfected brown rice into the CaCl2 germination accelerating solution for germination treatment, and grinding to obtain germinated brown rice slurry; s2, adding liquefying enzyme and saccharifying enzyme into the germinated brown rice pulp, and performing enzymolysis to the end point to obtain brown rice saccharified liquid; s3, saccharomyces cerevisiae CGMCC No.33650 is inoculated into a glucose culture medium for aerobic culture, and a seed solution is obtained; s4, inoculating the seed solution into a culture solution containing a brown rice saccharification solution, and carrying out aerobic fermentation to an end point to obtain a fermentation solution; s5, performing centrifugal treatment on the fermentation liquid to obtain germinated brown rice fermentation product filtrate. The filtrate of the fermentation product is rich in GABA, amino acid, protein, small molecular organic acid and phenolic substances, retains mellow wine fragrance and does not contain alcohol; the whitening and brightening effects, the anti-wrinkle and repairing effects, the anti-aging effect, the anti-oxidation effect, the soothing effect, the moisturizing effect and the like are realized.

The invention relates to the technical field of food processing and functional beverages, in particular to a preparation technology of wheat germ pulp, the wheat germ pulp and a functional beverage containing the wheat germ pulp. According to the preparation process of the wheat germ pulp provided by the invention, the pulsed electric field is applied in the gelatinization process, a specific enzymolysis sequence of amylase, saccharifying enzyme and cellulase is adopted, and ultrasonic treatment is carried out during first enzymolysis, so that the sugar degree and yield of the wheat germ pulp are remarkably improved, and meanwhile, the pulp viscosity is reduced; the taste of the wheat germ pulp is effectively improved.

The invention relates to the technical field of feeds, in particular to a diatomite carrying agent enriched rice polysaccharide feed and a preparation method thereof. The raw materials comprise diatomite, rice, glutinous rice, flour, dry yeast, beer yeast, rhizopus sweet rice wine koji, raw rice flour, glutinous rice flour, brown sugar, soybean meal, saccharifying enzyme, sodium propionate, sodium lactate, astragalus membranaceus, liquorice, angelica sinensis, radix angelicae, clove, malt, momordica grosvenori, codonopsis pilosula and flaccid knotweed herb. The diatomite carrying agent enriched rice polysaccharide feed disclosed by the invention contains extremely rich polysaccharides, and is safe and nutritional; the preparation process of the feed is ecological and environment-friendly, can be fully copied, is easy to prepare, low in price and remarkable in economic benefit, meanwhile, the value of the rice is increased, and the feed has great strategic significance for maintaining food safety.

The present invention provides a method for preparing polygonatum wine, which comprises mixing polygonatum with saccharifying enzyme for saccharification and then mixing with saccharomyces cerevisiae FN107 bacterial liquid for fermentation. Compared with the traditional fermentation koji, the optimized fermentation process has the advantages of fast fermentation speed, convenient process operation, rich in polysaccharides, the main functional component of polygonatum, and can effectively improve the utilization efficiency of polygonatum, enrich the product types of polygonatum, expand the polygonatum industry chain, and thus promote the polygonatum industry.

The invention relates to the field of preparation of rice drinks, in particular to a preparation method of a rice drink, which comprises the following steps: S1, cleaning rice, and soaking for 25 minutes in summer and 35-40 minutes in winter; s2, adding water into the soaked rice according to the material-liquid ratio of 1: 12.5, and smashing the rice into pulp by pulping equipment; s3, adjusting the pH value of the rice milk to 5.0-5.6, and adding high-temperature alpha-amylase for liquefying; s4, adding saccharifying enzyme into the liquefied rice milk for saccharifying; s5, adjusting the pH value of the saccharified raw materials to 6.5-7.5, and adding protease for enzymolysis; s6, the rice milk obtained after enzymolysis is filtered through a 200-mesh filter; s7, the rice milk is compounded with oat juice, and white sugar, an emulsion stabilizer and curdlan are added for blending; s8, the compound mixture is homogenized through a high-pressure homogenizer; s9, performing sterilization treatment on the rice juice beverage; and S10, performing sterile filling on the sterilized rice juice beverage, and converting the rice into the rice beverage which is good in stability and not easy to stratify through a series of process steps.

The invention belongs to the field of biomass-based functional materials, relates to a difunctional coating based on enzymolysis modified cassava starch as well as a preparation method and application of the difunctional coating, and innovatively solves the technical problem that a single coating gives consideration to oil prevention and water absorption through a synergistic technical path of pretreatment and composite enzymolysis. The core mechanism is as follows: the starch particle structure is destroyed through pretreatment, and the degradation degree of starch is accurately controlled through the synergistic effect of alpha-amylase and saccharifying enzyme, so that an unexpected technical effect is achieved, and an enzymolysis product with a film-forming skeleton (medium molecular weight dextrin) and a hydrophilic unit (small molecular saccharide) is formed; meanwhile, a compact and continuous network structure can be formed by a film-forming framework, and grease permeation is blocked; and the hydrophilic unit endows the coating with a rapid capillary water absorption effect.

The invention discloses a method for producing phloretin by using saccharomyces cerevisiae, and belongs to the technical field of microbial genetic engineering. A natural metabolic phloretin path in a plant is successfully constructed in the saccharomyces cerevisiae BY4741, synthesis of phloretin in microorganisms is achieved, synthesis of the phloretin in the microorganisms is enhanced by enhancing synthesis path genes of tyrosine and phenylalanine in the saccharomyces cerevisiae, including elimination of tyrosine feedback inhibition and introduction of exogenous genes, synthesis of prerequisite tyrosine and phenylalanine is enhanced, and the yield of the phloretin is increased. And the yield of the phloretin is further improved by enhancing the expression of a key gene in a phloretin synthesis pathway. The yield of phloretin synthesized from the beginning by the engineering yeast can reach 246.21 mg / L, the synthesis problem of phloretin serving as a carbohydrase inhibitor is effectively solved, and a foundation is laid for synthesizing phloretin through efficient fermentation of microorganisms.

The invention discloses high-purity resistant dextrin and a preparation method thereof, and the preparation method comprises the following steps: (1) adding 4, 3-alpha-glucosyltransferase into a maltodextrin aqueous solution or a starch solution treated by starch debranching enzyme to react, and after the reaction is finished, deactivating the enzyme; (2) adding alpha-amylase into a reactant in the step (1) to react, and deactivating the enzyme after the reaction is finished; (3) adding alpha-glucosidase into the reactant in the step (2) for reaction, and deactivating the enzyme after the reaction is finished; (4) adding saccharifying enzyme into the reactant in the step (3) to react, and deactivating the enzyme after the reaction is finished; and (5) adding yeast powder into the reactant in the step (4) for fermentation, filtering by a filter membrane after fermentation, collecting membrane filtrate, and drying to obtain the high-purity resistant dextrin. The preparation process is simple and efficient, the product purity is high, the proportion of alpha-1, 3 glucosidic bonds in the prepared resistant dextrin is 40% or above, and the purity of the resistant dextrin is 80-90%.

The invention belongs to the technical field of biology, and relates to a method for preparing peony seed protein from an oil peony byproduct. The peony seed protein is obtained by taking oil peony seed meal as a raw material and adopting a separation and purification method of protease enzymolysis, saccharifying enzyme desugaring, centrifugation, microfiltration and ultrafiltration. The peony seed protein disclosed by the invention is low in alkali consumption and dosage, simple to operate and high in solubility.

The application discloses a method for preparing an oat-based beverage through biological enzymolysis and a product thereof, and comprises the following steps: continuously hydrolyzing starch, cellulose, protein and other substances in oat slurry by using high-temperature-resistant amylase, cellulase, saccharifying enzyme, papain and alkaline protease, sufficiently releasing reducing substances in the oat, simultaneously generating reducing peptides, improving the free radical scavenging capacity of the oat slurry, and improving the emulsification stability of the oat slurry due to the moderate degradation of macromolecular substances such as starch, cellulose and protein; glycerol is added in three stages at a controlled speed, so that the glycerol is fully mixed with flaxseed oil, and excessive glycerol is avoided from adhering to lipase to reduce the activity of the enzyme, thereby improving the reaction efficiency.

The application discloses a method for improving the protein secretion capacity of Aspergillus and a recombinant strain obtained from the method. An16g07795 The method comprises performing genetic operation on Aspergillus to delete or reduce the activity of specific genes An16g07795 , so as to improve the protein secretion capacity of saccharifying enzyme, alpha-amylase, other proteins participating in starch hydrolysis and the like. The application utilizes the CRISPR-Cas9 genome editing technology to knock out the genes of Aspergillus niger, obtains a gene editing deletion mutant strain, and significantly improves the production level of starch hydrolysis enzymes, including the protein secretion level and the activity of saccharifying enzyme, so the application has great application value.

The present application relates to the field of food processing, and particularly relates to a preparation method of quinoa and red date yoghurt. The method comprises the following steps: quinoa is soaked, ground, and treated by gradient temperature enzyme inactivation, and then mixed with red date pulp at a volume ratio of 1:1, and then treated by alpha-amylase liquefaction, saccharifying enzyme and pullulanase compound saccharification, and low-oxygen flavor pre-hybridization, and then mixed with reconstituted milk and compound stabilizer konjac glucomannan and sodium pyrophosphate, and then sterilized, cooled, inoculated with starter culture, and then fermented and ripened to obtain the product. The present application eliminates the peculiar smell of quinoa by gradient enzyme inactivation, and saccharifying enzyme and pullulanase have a significant synergistic effect in the quinoa and red date yoghurt system, and the secondary enzymolysis of liquefaction and saccharification significantly improves the starch utilization rate, and the compounding of konjac glucomannan and sodium pyrophosphate significantly improves the product texture, and the present application solves the technical problems of low starch utilization rate, obvious peculiar smell, poor water holding capacity, and low viable count of traditional quinoa yoghurt.

The invention relates to the technical field of membrane separation, in particular to a glucose mother liquor nanofiltration membrane filtration parameter dynamic optimization process which comprises mother liquor pretreatment, intelligent nanofiltration filtration, clear liquid treatment, residual liquid deep saccharification and finished product preparation. A sulfonated chitosan-graphene modifier is added during pretreatment, a polyamide membrane is adopted for nanofiltration, the temperature, pressure and flow velocity are dynamically adjusted through a PLC-AI system, a TiO-ZnO nano liquid is synchronously added, clear liquid is concentrated, composite saccharifying enzyme is added for reaction, enzyme is added into residual liquid, nano aerogel is saccharified, and a finished product is dried through pulse hot air circulation. According to the process, AI dynamic regulation and control are combined with a nano material, so that the pollution resistance of a nanofiltration membrane is improved, the purity of glucose is improved to 92% or above, the yield is higher than 89%, oligosaccharide residues in saccharified liquid are reduced, drying energy consumption and COD emission are reduced, and high-value utilization of mother liquor is realized.

The invention provides a preparation method of rice bran fermentation product filtrate as well as a product and application thereof. The preparation method comprises the following steps: (1) sterilizing rice bran, mixing the sterilized rice bran with compound enzyme and water, adjusting the pH value, performing enzymolysis reaction, and performing enzyme deactivation after the enzymolysis reaction is finished to obtain rice bran zymolyte; the compound enzyme comprises alpha-amylase, beta-xylosidase and saccharifying enzyme; (2) mixing the rice bran zymolyte, an auxiliary carbon source and water to prepare a fermentation substrate; and (3) inoculating compound bacteria into the fermentation substrate for fermentation, sterilizing after fermentation, and carrying out solid-liquid separation to obtain the rice bran fermentation product filtrate. According to the method, active ingredients in the rice bran can be fully and effectively extracted and utilized, the stability and the absorption rate of the rice bran fermentation product filtrate are improved, and the prepared rice bran fermentation product filtrate contains rich effective ingredients such as ceramide, vitamins, polyphenol compounds and trace elements; the composition has excellent soothing, repairing and anti-oxidation effects.

The invention provides a preparation method and application of high-palatability carrot dietary fibers. The method comprises the following steps: (1) washing and dicing carrots; (2) cellulase and saccharifying enzyme enzymolysis; (3) constructing a two-phase system, adding a compound enzyme and pectinase, and carrying out gradient enzymolysis; (4) carrying out enzyme deactivation and centrifugation to obtain a water phase; (5) performing gradient centrifugation to obtain mixed fibers; (6) precipitating, and collecting precipitated fibers; (7) adding carrot source nano cellulose to obtain a composite fiber with a core-shell structure; and (8) drying, crushing and sieving. According to the preparation method disclosed by the invention, the core problems of rough taste (large particle size), astringent taste (residual acetyl groups and terpene substances), weak function and low purity in the traditional carrot dietary fiber preparation process are solved through a water-alcohol two-phase gradient composite enzymolysis and nano cellulose composite purification process; and finally, the high-palatability carrot dietary fiber which is fine, smooth, free of rough feeling, natural, fresh and sweet, high in purity and strong in function is prepared.

The invention discloses paenibacillus polymyxa FF1901 derived from animal intestinal tracts and an application of the paenibacillus polymyxa FF1901. The invention provides paenibacillus polymyxa, the paenibacillus polymyxa is paenibacillus polymyxa FF1901, and the preservation number of the paenibacillus polymyxa is CGMCC (China General Microbiological Culture Collection Center) No.33724. The paenibacillus polymyxa has the advantages that the paenibacillus polymyxa FF1901 is used as a culture medium; the invention also provides a paenibacillus polymyxa culture which is a substance obtained by culturing the paenibacillus polymyxa in a microbial culture medium or a supernatant of the substance. The paenibacillus polymyxa FF1901 or the culture of the paenibacillus polymyxa FF1901 provided by the invention can be used for remarkably inhibiting various pathogenic bacteria and potential pathogenic fungi; certain intestinal environment tolerance and colonization capability are realized; good carbohydrate enzyme activity is achieved, and the carbohydrate enzyme comprises cellulase, protease and amylase; good anti-inflammatory activity is realized.

The invention relates to the technical field of emulsification processes, in particular to a camellia oil emulsification production process. Comprising the following steps: step 1, mixing cassava starch with water to prepare starch milk; step 2, adding saccharifying enzyme and alpha-amylase into the starch milk, adding bacillus firmus for fermentation reaction, and after the reaction, inactivating the bacillus firmus, the saccharifying enzyme and the alpha-amylase to obtain a fermentation product; and step 3, mixing the fermentation product, camellia oil, sorbate monostearate, L-ascorbyl palmitate, cocoa butter, water and lecithin according to a mass ratio to obtain a mixture, heating the mixture to 40-45 DEG C, adjusting the pH value to 6-8, and circularly treating the mixture for 3-5 times under the pressure of 90-100 MPa through a high-pressure homogenizer to obtain a homogeneous emulsion. The prepared camellia oil emulsified product can still maintain a good gastric mucosa repairing effect after being stored for more than 24 months under a normal-temperature indoor illumination condition.

This invention discloses a method for preparing fermented Chinese medicine wine, comprising the following steps: S1: Preparing brewing grains by weight, soaking, steaming, and treating with saccharifying enzymes to obtain saccharified grains; S2: Treating Chinese medicinal materials with compound enzymes to obtain enzymatically hydrolyzed Chinese medicinal materials; S3: Mixing the saccharified grains and enzymatically hydrolyzed Chinese medicinal materials, adding yeast for anaerobic fermentation to obtain fermented material; S4: Distilling and aging the fermented material to obtain fermented Chinese medicine wine. The advantages of this invention compared to existing technologies are: providing a method for preparing fermented Chinese medicine wine that achieves efficient release and full conversion of the effective components of Chinese medicinal materials, ensuring a mellow flavor and stable quality.

The application belongs to the technical field of vinegar brewing, and provides a compound koji inoculated with indigenous Aspergillus oryzae and Aspergillus niger and a method for strengthening Shanxi old mature vinegar. Indigenous Aspergillus oryzae CGMCC 42103 with high yield of acid protease and glutaminease and Aspergillus niger CGMCC 15672 with high yield of saccharifying enzyme are mixed and inoculated in bran and soybean powder medium to prepare compound koji, and the prepared compound koji is applied to the fermentation process of Shanxi old mature vinegar to prepare new vinegar, the total acid, amino acid nitrogen, non-volatile acid and glutamic acid content of the new vinegar are 6.18 g / 100 mL, 0.38 g / 100 mL, 2.45 g / 100 mL and 58.83 mg / 100 mL respectively, compared with the comparative example in which only highland millet with a mass fraction of 60% is added in the alcohol fermentation stage to carry out conventional fermentation of food vinegar, the new vinegar is improved by 20.47%, 153.33%, 33.15% and 118.86% respectively, and the content of organic acid and volatile aroma components is enriched.

The method for catalytically preparing D-mannose provided in the application can effectively reduce the amount of by-products glucose and fructose, and greatly improve the conversion rate of D-mannose. Specifically, the engineering bacteria expressing isoamylase gene and the engineering bacteria expressing alpha-glucan phosphorylase gene, glucose phosphomutase gene, bifunctional enzyme glucose phosphate isomerase / mannose 6-phosphate isomerase gene and mannose 6-phosphate phosphatase gene are used, starch or starch derivatives are used as substrates, phosphate buffer solution and Mg 2+ A preliminary catalytic system is constructed, and after the reaction is completed, there are unreacted substrates and maltodextrin in the reaction system, the saccharifying enzyme can hydrolyze the unreacted substrates and maltodextrin into glucose, the polyphosphate glucose kinase can convert all the glucose into phosphorylated glucose with the assistance of sodium hexametaphosphate, and then D-mannose is generated, thereby improving the yield and removing the by-products in the system.

The present application relates to the technical field of starch coating, in particular to a preparation method of structured starch coating liquid with oil-proof and moisture-absorbing dual functions. The method comprises the following steps: firstly, performing mild acidolysis or selective oxidation pretreatment on cassava starch; then, preparing starch milk by using the pretreated starch, and performing synergistic enzymolysis on the starch milk under mild conditions by using a composite enzyme composed of alpha-amylase and glucoamylase in a specific ratio; after the enzymolysis, performing enzyme inactivation treatment, and then adding a bio-based crosslinking agent for compounding. The prepared coating has a specific bimodal distribution structure of starch derivative molecular weight, which is a key to realize function balance. After the coating liquid is coated on a substrate such as paper and dried and solidified, the formed coating not only has excellent oil-proof performance, but also exhibits good water vapor absorption capacity. The raw materials of the present application are green and the process is environmentally friendly, and the prepared multifunctional coating can be effectively applied to the fields of food packaging, medical protection and other fields which need to resist oil and regulate humidity at the same time.

The present invention provides a method for improving the digestibility of a carbohydrate by a carbohydrase in an animal feed such as soybean-meal, corn, wheat, wheat middlings, oats, rye, barley and sorghum; and / or roughages such as hay and pasture plants, or mixture thereof by adding one or more proteases, preferably a serine protease such as a Nocardiopsis serine protease or a S8 serine protease. The present invention also provides a feed composition suitable for the above methods.