641 results about "Yeast extract" patented technology

The invention relates to a concrete anti-cracking self-repairing agent in the technical field of building materials, and aims to solve the problem that concrete cracks are difficult to self-repair. According to the technical scheme, the self-repairing agent is characterized by comprising a microbial repairing unit formed by ZSM-5 type zeolite molecular sieve loaded bacillus pasteurii spores, mesoporous silica particles loaded with L-calcium aspartate and Fe3O4 (at) SiO2 core-shell nanoparticles which are fixed through an in-situ polymerization coating layer to form a magnetic thermal response capsule layer coating the surface of the microbial repairing unit, pLGA microspheres containing yeast extract are positioned on an interface of zeolite and hydrogel, and a trehalose-anhydrous calcium chloride eutectic compound is used as a directional mineralization accelerant. The concrete anti-cracking self-repairing agent provided by the invention is mainly used for intelligent identification and self-repairing of concrete cracks, and efficient repairing is realized through a microbial mineralization, calcium ion slow release and magnetic thermal response synergistic mechanism.

The invention relates to the technical field of environmental restoration, in particular to a slow-release material for synergistically restoring heavy metal and organic compound contaminated soil based on modified biochar and microorganisms and an application method thereof.The slow-release material is prepared from, by weight, 50-80 parts of modified biochar, 30-40 parts of sodium alginate, 10-20 parts of gelatin, 5-10 parts of glycerin and 3-5 parts of calcium carbonate. The multi-modified biochar is prepared from, by weight, 300-400 parts of a functional flora mixed solution and 5-10 parts of mixed nutrient elements of glucose, yeast extract and KHPO, and through the synergistic effect of the multi-modified biochar and the functional flora, efficient immobilization (the immobilization rate gt is 60%) of heavy metal (lead, cadmium and chromium) and efficient degradation (the degradation rate gt is 70%) of organic pollutants (polycyclic aromatic hydrocarbon and petroleum hydrocarbon) are achieved.

The invention relates to a functional microorganism-containing organic-inorganic compound fertilizer and a production method thereof, and relates to the technical field of fertilizers, the functional microorganism-containing organic-inorganic compound fertilizer comprises an inorganic core layer, an organic coating layer and a functional microorganism outer layer, the functional microorganism outer layer comprises the following components in parts by mass: 10-15 parts of compound functional microorganisms, 5-10 parts of synergistic growth-promoting microorganisms, 2-3 parts of trehalose, 1-2 parts of mannitol, 10-15 parts of sodium alginate, 8-10 parts of chitosan, 2-4 parts of a yeast extract and 30-40 parts of a modified activated carbon carrier. The production method comprises the following steps: preparing an inorganic core layer, preheating the inorganic core layer, and spraying and coating an organic coating layer material to obtain a primary product with an organic coating layer; and coating the surface of the organic coating layer of the primary product with a functional microorganism outer layer material, drying at low temperature, and screening to obtain the organic-inorganic compound fertilizer containing the functional microorganisms. The fertilizer has the effect of improving the slow release effect of the fertilizer and the survival rate of microorganisms.

The invention relates to the field of nutrient solutions, and particularly discloses a high-calcium-zinc dietary nutrient solution for promoting skeletal development and a preparation method thereof, the high-calcium-zinc dietary nutrient solution for promoting skeletal development comprises the following raw materials: calcium citrate, zinc citrate, a zinc-containing yeast extract, vitamin D3, a nutrition enhancer, functional oligosaccharide, xanthan gum, anhydrous citric acid, essence, a sweetening agent and water; the preparation method comprises the following steps: mixing the zinc citrate, the zinc-containing yeast extract, the seaweed meal, the natto powder, the stachyose and the trehalose to prepare a mixture A; uniformly premixing stevioside, xanthan gum and trehalose to obtain a mixture B; s4, vitamin D3 powder and trehalose are premixed and dissolved, and a mixture C is prepared; heating the residual water, adding the mixture A, the fructo-oligosaccharide, the anhydrous citric acid, the calcium citrate, the mixture B, the trehalose and the mixture C, adding the essence, and stirring to obtain the beverage. The preparation method has the characteristic of preparing the liquid calcium-zinc dietary nutrient solution with good absorption and utilization rate and palatability.

The application relates to an organic-inorganic compound fertilizer containing functional microorganisms and a production method thereof, and relates to the technical field of fertilizers. The fertilizer comprises an inorganic core layer, an organic coating layer and a functional microorganism outer layer. The functional microorganism outer layer comprises the following components in mass fractions: 10-15 parts of compound functional microorganisms, 5-10 parts of synergistic growth-promoting microorganisms, 2-3 parts of trehalose, 1-2 parts of mannitol, 10-15 parts of sodium alginate, 8-10 parts of chitosan, 2-4 parts of yeast extract and 30-40 parts of modified active carbon carriers. The production method comprises the following steps: preparing the inorganic core layer, preheating the inorganic core layer, spraying the organic coating layer material to coat the surface, and obtaining a preliminary product with the organic coating layer; coating the functional microorganism outer layer material on the surface of the organic coating layer of the preliminary product, low-temperature drying and screening, and obtaining the organic-inorganic compound fertilizer containing the functional microorganisms. The application has the effects of improving the slow-release effect of the fertilizer and the survival rate of the microorganisms.

The invention belongs to the field of analytical chemistry and mathematical modeling, and particularly relates to a method for predicting and identifying whether soy sauce contains yeast extracts, which comprises the following steps: 1) taking different types of soy sauce as modeling samples; 2) carrying out decolorization pretreatment on the modeling sample; (3) carrying out spectrum scanning on the modeling sample by adopting a Raman spectrum technology to obtain original Raman spectrum information; 4) preprocessing the Raman spectrum data obtained in the step 3); 5) sampling for multiple times to establish a sparse logistic regression model, and recording important wave numbers; 6) counting wavenumber importance; 7) selecting an important wave number; 8) using TabPFN to establish a prediction model; (9) predicting and judging whether the yeast extract is added into the soy sauce sample or not by utilizing the established prediction model; compared with the prior art, the method can quickly and accurately identify whether the soy sauce such as light soy sauce and dark soy sauce contains the yeast extract or not, and is simple and quick in identification process, short in analysis time, high in accuracy and high in practicability.

The invention provides schizochytrium limacinum FJ-1 and application thereof in production of phospholipid type EPA (eicosapentaenoic acid). The application comprises the following steps: taking a cryopreserved schizochytrium limacinum strain, and inoculating the schizochytrium limacinum strain into a liquid seed culture medium for pre-culture; the method comprises the following steps: inoculating pre-cultured schizochytrium limacinum into a fermentation tank according to the inoculum size of 5-10% v / v, culturing for 48-60 hours at the sea salt concentration of 0.5-1% w / v, fermenting for 48-72 hours, supplementing sea salt to a culture medium in batches until the sea salt concentration is 3-5% w / v, and continuously culturing for 96-120 hours by controlling the glucose concentration and the yeast extract concentration through supplementing materials. The technical problem that the synthesis efficiency of schizochytrium limacinum phospholipid type EPA is low is solved through precise regulation and control of salinity stress, an efficient, economical and generalizable innovative scheme is provided for industrial production of functional lipid, and the method is suitable for large-scale production.

The invention relates to the technical field of bacterium enrichment nutrient solutions, in particular to a bacterium enrichment nutrient solution for fermentation and a preparation method of the bacterium enrichment nutrient solution. The culture medium is prepared from the following raw materials in parts by weight: maltodextrin, crystalline glucose, low-pigment yeast extract powder, refined soy peptone, dipotassium phosphate, monopotassium phosphate, magnesium sulfate heptahydrate, sodium chloride, phytic acid, L-ascorbic acid, manganese sulfate monohydrate, biotin, thiamine hydrochloride and choline chloride. Through a double-carbon-source structure, maltodextrin and crystalline glucose cooperate, metabolic oscillation is avoided, and the energy utilization rate is increased; the low-pigment yeast extract powder and the refined soy peptone are complementary, so that the rapid growth requirement of thalli is met; phytic acid is chelated with metal ions to prevent precipitation, L-ascorbic acid is used for resisting oxidation, and biotin and thiamine activate a coenzyme pathway to realize accurate regulation and control of a metabolic network.

An object of the present invention is to provide a lactase solution showing good permeation through a filtration filter, a lactase solution showing good permeation through a filtration filter and having a good residual lactase activity, and a lactase solution showing good permeation through a filtration filter and having a good residual lactase activity even when a lactase solution having a low protease activity and a low arylsulfatase activity as contaminant enzymes is used.A lactase solution containing any of (i) to (iii) below.(i) 0.0001 to 0.1 mass % of an unsaturated fatty acid or a salt thereof(ii) 0.0001 to 0.1 mass % of a saturated fatty acid salt(iii) 0.01 to 10 mass % of at least one selected from yeast extract, soybean peptone, pea protein, a casein degradation product, and corn steep liquor

The invention discloses a culture medium for increasing the yield of paracoccus astaxanthin and application of the culture medium. The culture medium comprises the following components according to concentration: 4-20g / L of yeast extract; 8-20 g / L of beef extract; 4 to 20 g / L of bacteriological peptone; 10 to 30 g / L of glucose; the concentration of KH2PO4 is 0.1 to 0.2 g / L; the concentration of Na2HPO4. 12H2O is 0.1 to 0.5 g / L; 0.1 to 1 g / L of MgSO4. 7H2O; 0.1 to 1 g / L of FeSO4. 7H2O; the concentration of CaCl2. 2H2O is 0.02 to 0.1 g / L; the pH is 7.2 + / -0.2. The yeast extract, the beef extract and the bacteriological peptone are selected and mixed to serve as a nitrogen source, accumulation of paracoccus biomass and astaxanthin can be promoted synergistically, and meanwhile the problem of precipitation after the culture medium is sterilized is solved.

The invention relates to the technical field of food, and particularly provides a preparation method and application of an oyster sauce based on Sanzan gum. The Sanzan gum is used as a raw material for preparing the oyster sauce for the first time, the preparation method of the oyster sauce is optimized, the problems of poor stability and high cost of the oyster sauce can be effectively solved, and meanwhile, the texture characteristics of the oyster sauce are improved. More specifically, in the raw materials of the oyster sauce, the flavoring substances comprise oyster juice, edible salt, white granulated sugar, a yeast extract and sodium glutamate; in the stabilizer of the oyster sauce, the ratio of hydroxypropyl distarch phosphate to Sanzan gum is (1-8): (0.1-0.4). The Sanzan gum endows the oyster sauce with relatively good firmness, viscosity, cohesiveness, viscosity index and taste; moreover, the shelf life is prolonged while the addition amount of the Sanzan glue is small, and the production cost of the oyster sauce can be effectively reduced.

The invention belongs to the technical field of edible flavors and fragrances, and particularly relates to a method for preparing bidirectional controlled-release meat flavor by using bean dreg protein. The method comprises the following steps: taking bean dreg protein as a raw material, mixing bean dreg protein zymolyte, yeast extract, amino acid or peptide, reducing sugar and grease, carrying out three-stage heating, and respectively mixing the three-stage heating products according to a specific ratio. The obtained essence has the characteristic of bidirectional controlled-release fragrance, is pure, strong, mellow and vivid in meat flavor, can be well applied to food seasonings, and has a wide application prospect.

The invention discloses an improved self-induction culture medium and a culture process, and belongs to the technical field of bioengineering. The improved self-induction culture medium is prepared from 10 g / L of glucose, 3-5 g / L of glycerin, 3 g / L of lactose, 24 g / L of yeast extract, 8 g / L of casein hydrolysate, 0.02-0.05 mM of malonic acid, 1 mM of methionine and 1-3 mM of MgSO4, a phosphate buffer solution is added to control the pH to be 7.2, and the improved self-induction culture medium is prepared by mixing after sterilization. Cells are inoculated to an improved self-induction culture medium for culture, automatic switching of growth-induction stages can be realized based on a pH and DO linkage dynamic feeding control method, the operation complexity is reduced, and the controllability is higher. The culture medium does not need a special inducer, cost is reduced, and protein expression quantity is improved.

To provide a topical skin preparation that effectively promotes collagen production within the skin, exhibits excellent usability, and effectively enhances post-use stratum corneum moisture content.SOLUTION: A topical skin preparation comprises niacinamide, a heparin-like substance, dipotassium glycyrrhizinate, a collagen peptide, a yeast extract, and glycylglycine. It is preferable that the topical skin preparation further contains hydrogenated soybean phospholipids and phytosterols. It is more preferable that the topical skin preparation has a niacinamide content of 5 mass% or more. It is also preferable that the topical skin preparation further contains at least one plant extract selected from Arnica montana and Plantago major.SELECTED DRAWING: Figure 1

The invention belongs to the technical field of bioengineering, and particularly relates to kluyveromyces marxianus engineering bacteria for synthesizing eicosapentaenoic acid and application of the kluyveromyces marxianus engineering bacteria. According to the engineering bacterium, pyruvate decarboxylase PDC1 genes, alcohol dehydrogenase ADH1 genes and alcohol dehydrogenase ADH2 genes are sequentially knocked out from a kluyveromyces marxianus FIM1 delta ura3 strain; meanwhile, a citrate lyase ACL gene, a pyruvate oxidase PO gene and a phosphate transacetylase PTA gene are inserted into the loci respectively, so that synthesis of acetyl coenzyme A is enhanced; then a plurality of genes are sequentially inserted into a Kluyveromyces marxianus genome, and then a vector of a delta 8 desaturase delta 8D gene is transferred into the Kluyveromyces marxianus genome. The invention also provides a method for efficiently preparing the EPA, namely the Kluyveromyces marxianus engineering strain is used as a fermentation strain, glucose, a yeast extract, peptone and other components are used as a culture medium, and the yield of the EPA produced by culturing and fermenting reaches 8.71 mg / g of dry cell weight.

The invention relates to the technical field of agricultural waste recycling and feed industry, in particular to a traditional Chinese medicine residue feed additive as well as a preparation method and application thereof. The preparation method comprises the following steps: drying traditional Chinese medicine residues, crushing to obtain a crushed material, mixing the crushed material with a compound enzyme, carrying out enzymolysis to obtain an enzymolysis material, mixing the enzymolysis material with lactobacillus plantarum LP-01, carrying out anaerobic fermentation to obtain a fermented material, mixing the fermented material with a yeast extract and manganese sulfate to obtain a mixture, mixing the mixture with water, extracting, filtering to obtain a filtrate, concentrating, and carrying out freeze drying to obtain a finished product. The traditional Chinese medicine residue feed additive is obtained. By adopting the traditional Chinese medicine residue feed additive provided by the invention, the diarrhea rate of weaned piglets can be reduced, the stress resistance of aquatic animals is improved, and the growth performance of poultry is improved.

The invention provides a preparation method of composite degradable TIEL aerogel, and relates to the technical field of production of TIEL aerogel. The preparation method of the composite degradable TIEL aerogel comprises the following steps: S1, firstly, preparing a culture medium, and dissolving 20g / L of glucose, 5g / L of yeast extract, 5g / L of peptone, 2.7 g / L of Na2.HPO4, 0.5 g / L of MgSO4. 7H2O and 1.5 g / L of citric acid in deionized water; s2, adjusting the pH value of the culture medium with HCl, then performing high-temperature sterilization treatment on the culture medium, cooling the culture medium to room temperature, inoculating pre-cultured acetobacter aceti into the culture medium, performing static culture for 7 days at 30 DEG C, then repeatedly cleaning the harvested film with deionized water, and removing impurities with an alkaline solution to obtain a fresh bacterial cellulose film. According to the cellulose aerogel, chitosan is introduced as a natural electron donor, so that the triboelectric property of the cellulose aerogel is optimized, and meanwhile, the degradability is kept.

This invention provides a novel method for preparing a medical collagen sponge, relating to the field of medical sponge technology. The invention uses yeast extract obtained by Soxhlet extraction of brewer's yeast as a raw material, which is mixed and reacted with polyvinyl alcohol and graphene oxide to obtain the novel medical collagen sponge. The medical collagen sponge prepared by this invention exhibits excellent performance and good hemostatic effect. Furthermore, the preparation method is simple, and it degrades postoperatively, demonstrating significant application value in the field of medical materials.

The invention discloses a method for improving the fermentation performance of clostridium aerovorans and application of the clostridium aerovorans, and according to the method, an effective amount of methionine or a derivative thereof is added into a fermentation culture medium of the clostridium aerovorans to completely replace expensive complex organic nitrogen sources such as yeast extracts. The method successfully solves the three technical bottlenecks of slow biomass accumulation, low ethanol yield and dependence on expensive nitrogen sources in the fermentation process of the clostridium aerovorans by utilizing synthesis gas or CO2 / H2 mixed gas. Experiments prove that methionine or a derivative thereof can synergistically promote growth metabolism of thalli and a synthesis path of a product, so that the gas conversion efficiency of a carbon source is remarkably improved and metabolism is guided to flow to ethanol synthesis while the growth rate and the final biomass of the thalli are improved, and thus the production capacity of alcohols is synchronously enhanced. The method is simple in process and remarkable in effect, and an efficient and economical new strategy is provided for reducing the production cost of biofuel and promoting industrial application of a synthesis gas biorefinery technology.

The invention relates to the technical field of pet food, in particular to flavoring agent powder for pet dogs and a preparation method of the flavoring agent powder. Comprising the following raw materials: 40 parts of beef liver, 10 parts of hairtail, 7-40 parts of ricefield eel, 1 part of protease, 0.5-1 part of lipase, 0.5-1 part of flavor enzyme, 5-10 parts of saccharides, 10 parts of fish oil, 5-10 parts of maltodextrin, 0.5-1 part of sodium hydroxide, 5 parts of phosphoric acid, 3 parts of amino acid, 2 parts of thiamine, 1 part of yeast extract and 0.5-1 part of lactoferrin. The dog feed can increase the appetite of dogs from the sense of smell, maintain the health balance of intestinal flora of dogs and improve the micro-ecological environment of intestinal tracts.

The invention relates to the technical field of microbial fermentation, in particular to a fermentation medium for producing oxytetracycline. According to the fermentation culture medium, a corn starch-molasses-wheat hydrolyzed sugar composite carbon source, a soybean cake powder-corn steep liquor-yeast extract composite nitrogen source and a choline chloride-betaine-L-lysine precursor accelerant in a specific proportion are used as a core innovative system, and a form regulating agent, a defoaming agent and inorganic salt are cooperatively added. Through the synergistic effect of multiple components, the fermentation titer and yield of oxytetracycline are remarkably improved, the fermentation period is shortened, the generation of heteroacid is effectively inhibited, the mycelium form is optimized, and the oxytetracycline fermentation medium is suitable for industrial large-scale production of oxytetracycline.

The present invention relates to the field of biotechnology, and particularly to a preparation method of yeast extract rich in betaine. The present invention provides a preparation method of yeast extract rich in betaine. Among them, the yeast extract rich in betaine includes protein, amino acids, peptides, nucleotides, and betaine. The mass percentage content of protein is 50% - 75%, and the mass percentage content of betaine is 0.2% - 4%. In the present invention, yeast rich in betaine is obtained by the yeast absorbing and enriching betaine in the betaine-rich carbon source during the growth process, and then the yeast extract rich in betaine is obtained through enzymatic hydrolysis and refinement. This technology makes up for the blank of yeast extract of betaine, and is mainly involved in the fields of food, health food, feed, medicine, etc.

The invention relates to the technical field of animal feed, in particular to a high-efficiency growth-promoting pig compound additive and a preparation method thereof. The high-efficiency growth-promoting pig compound additive is prepared from the following raw materials in parts by weight: 5-8 parts of bacillus subtilis; 3 to 5 parts of bacillus licheniformis; 4 to 6 parts of fructo-oligosaccharide; 3 to 5 parts of galactooligosaccharide; 8 to 12 parts of yeast extract; 2-4 parts of a yucca extract; 1 to 2 parts of cellulase; 1-2 parts of acid protease; 0.5 to 1.5 parts of curcumin; 0.3 to 0.8 part of tea polyphenol; 1-3 parts of taurine; and 2 to 4 parts of glycine chelated zinc. According to the efficient growth-promoting pig compound additive and the preparation method thereof, multi-dimensional collaborative optimization is adopted, probiotics and prebiotics are combined, colonization of beneficial bacteria in intestinal tracts is promoted, metabolic active substances are generated, antibiotic dependence is replaced, organic microelements are used for replacing high-dose inorganic zinc, and the risk of environment residues is reduced; the natural anti-inflammatory component and the light stabilizer reduce oxidative stress and photosensitive toxicity, are significantly superior to the traditional scheme, and have both environmental friendliness and cost effectiveness.

The invention discloses a fermentation process for shortening a fermentation period and efficiently synthesizing Ectoine. The fermentation process comprises the following steps: screening and activating high-yield strains, preparing a fermentation culture medium, performing fermentation culture, performing sectional dissolved oxygen regulation and control, performing double-stage pH dynamic regulation and control, performing carbon-nitrogen ratio dynamic regulation based on metabolic flow analysis, performing osmotic pressure gradient induction in the later stage of fermentation, and extracting and purifying a product. According to the fermentation process for shortening the fermentation period and efficiently synthesizing the Ectoin, the expression quantity of key enzymes for synthesizing the Ectoin is increased by 80% or above compared with that of an original strain through the Halomonassp.ECT-09 strain bred through ultraviolet-nitrosoguanidine compound mutation, the basic yield reaches 35 g / L, a foundation is laid for high yield, and the method is suitable for industrial production. A glucose-trehalose mixed carbon source and a yeast extract-ammonium nitrate mixed nitrogen source are adopted, and an L-aspartic acid-L-asparagine mixed precursor is added, so that the metabolic pathway is shortened, and the loss of an intermediate product is reduced.

The invention relates to the technical field of fermented beverages, in particular to a preparation method of a high-activity fruit and vegetable probiotic fermented beverage, which comprises the following steps: adding composite fruit and vegetable juice after enzymolysis, mineral water, xylooligosaccharide, grape seed extract, yeast extract and xanthan gum into a fermentation tank, and stirring until the materials are completely dissolved; then carrying out sterilization treatment by adopting high-temperature instantaneous sterilization; adding probiotic microcapsules into the sterilized mixed liquid, and performing staged temperature-controlled fermentation to obtain fermentation liquid; and performing homogenization treatment on the fermentation liquid, and finally performing vacuum degassing to obtain the high-activity fruit and vegetable probiotic fermented beverage. A composite wall material (sodium alginate-eucheuma powder-gellan gum) of the probiotic microcapsule forms a compact gel network to effectively isolate phenols, organic acids and other antibacterial components in fruits and vegetables, so that the damage of pH fluctuation and temperature change to thalli is resisted.

The invention discloses a method for screening and cultivating a bolete mutant strain, which belongs to the field of microorganisms, and mainly comprises the following steps: obtaining the bolete mutant strain by using a carbon ion beam irradiation technology, naming the bolete mutant strain as ng2, and preserving the bolete mutant strain with the preservation number of CCTCC (China Center for Type Culture Collection) M 2025077; inoculating the ng2 strain into a hypha rapid germination and propagation solid culture medium PDA or PDA + peptone + beef extract + yeast extract powder, wherein hypha begins to germinate after 4 days; the method comprises the following steps: inoculating a solid strain into a hypha rapid propagation liquid culture medium including cane sugar, corn flour, soybean flour, wheat bran, monopotassium phosphate and yeast extract powder, and generating a large amount of fungus balls within 7 days; inoculating a liquid strain into a fruiting culture raw material self-made fermentation material, corn straw, turfy soil and rice, wherein hyphae overgrow in 30 days; the ng2 strain is high in activity, high in growth speed and suitable for being used as an excellent bolete strain in the Heilongjiang region; the screening and cultivating method of the bolete mutant strain is mainly used for solving the problems that the propagation efficiency of the bolete strain is low, germplasm resources in northern areas such as Heilongjiang are deficient and the like.

The invention discloses a sports nutrition solid food for supplementing protein and a preparation method, and belongs to the technical field of foods.The sports nutrition solid food is prepared from, by weight, 31-60 parts of compound amino acid powder, 10-15 parts of isomaltitol, 1-6 parts of taurine, 1-5 parts of Chinese yam peptide, 5 parts of glycine, 5 parts of gamma-aminobutyric acid, 5 parts of L-lysine hydrochloride and 1 part of yeast protein powder. The formula comprises the following components in parts by weight: 1-3 parts of whey protein powder, 1-2 parts of hydroxymethyl propyl cellulose, 0.1-1 part of yeast extract, 0.1-1 part of yeast beta-glucan, 2-6 parts of bovine colostrum powder, 0.5 part of stevioside, 0.1 part of zinc glycinate, 0.1 part of ferrous lactate, 0.5 part of essence and 2-3 parts of magnesium stearate. The compound amino acid powder, the Chinese yam peptide, the glycine, the L-lysine hydrochloride, the yeast protein powder, the whey protein powder, the yeast extract and the bovine colostrum powder are compounded, so that protein consumed by a human body after exercise can be comprehensively supplemented.

The invention provides a beef essence preparation method and system based on dual enzymolysis-Maillard reaction synergistic interaction. The preparation method comprises the following steps: (1) carrying out first-step enzymolysis, namely adding compound protease into minced beef, regulating the pH value of a system to 6.5-7.0, controlling the temperature to be 45-50 DEG C, and carrying out enzymolysis reaction for 2-3 hours; (2) carrying out second-step enzymolysis, adding lipase derived from aspergillus oryzae, adjusting the pH value of the reaction system to 7.5-8.0, raising the temperature to 55-60 DEG C, and carrying out enzymolysis reaction for 1-2 hours; (3) performing enzyme deactivation treatment to obtain enzymatic hydrolysate; and (4) mixing the enzymatic hydrolysate with reducing sugar, thiamine and a yeast extract, and carrying out a Maillard reaction. The beef ingredients can be fully decomposed through double enzymolysis, and sufficient flavor precursor substances are provided for reaction; the Maillard reaction is intelligently regulated and controlled, more flavor substances are generated, and the flavor of the essence is remarkably improved.

The invention discloses a feed additive for improving the immunity of dairy cows in the perinatal period, and belongs to the technical field of nutritional feeds, the feed additive comprises the following components: nutritional additives: 500-1000 IU / kg of vitamin E, 0.1-0.3 mg / kg of selenium, 30-50 mg / kg of zinc, 10-20 mg / kg of copper, 20-40 mg / kg of manganese, 0.95-1.1 mmol / L of calcium and 10-20 mL / kg of linseed oil; and the non-nutritional additive comprises the following components: 1 to 5 * 10 < 9 > CFU / kg of lactic acid bacteria, 5 to 10 g / kg of prebiotics, 50 to 100 mg / kg of rosemary extract, 50 to 100 mg / kg of green tea extract and 50 to 100 mg / kg of yeast extract. Vitamin E, selenium, zinc, copper, manganese and other nutrients in the nutritional additive can enhance the oxidation resistance and immune function of dairy cows, so that various diseases including oxidative stress related diseases, infectious diseases, reproductive disorders, skeleton diseases and the like can be prevented.

The invention relates to the technical field of extraction of rare earth elements by a biological method, and provides a biological leaching method for extracting rare earth elements in fly ash by using aspergillus niger, which comprises the following steps: adding fly ash into a culture medium, sterilizing, inoculating aspergillus niger spore suspension, culturing, filtering leachate, and drying to obtain the rare earth elements, the culture medium consists of the following components in percentage by weight: 1-2% of glucose, 0.5-1.5% of a nitrogen source and the balance of water, the nitrogen source comprises peptone, yeast extract powder and diammonium hydrogen phosphate; the mass ratio of the peptone to the yeast extract powder to the diammonium hydrogen phosphate is 5: 1: (0.05-0.5). Through the technical scheme, the problem of low extraction rate of rare earth elements in related technologies is solved.