10results about How to "Lower water activity" patented technology

The invention discloses high-stability immobilized candida antarctica lipase B as well as a preparation method and application thereof, and belongs to the technical field of enzyme engineering and biological catalysis. The preparation method comprises the following steps: modifying resin by adopting a silane coupling agent to obtain silanized resin; carrying out aldehyde functional modification on the silanized resin by using dialdehyde cellulose to obtain alkyl-aldehyde modified resin; candida antarctica lipase B is immobilized by using alkyl-aldehyde modified resin, and after the Candida antarctica lipase B is subjected to interfacial activation on the surface of the alkyl-aldehyde modified resin, the Candida antarctica lipase B is covalently bound with aldehyde on the surface of the alkyl-aldehyde modified resin; the prepared immobilized Candida antarctica lipase B has relatively high activity and stability. The method is simple to operate, the prepared immobilized lipase is high in stability, and the method can be used for preparing the high-stability immobilized lipase on a large scale and has the potential of industrial popularization and application.

The invention provides a preparation method of alumina aerogel, and belongs to the field of aerogel. The method comprises the following steps: modifying industrial aluminum hydroxide, so that the industrial aluminum hydroxide is subjected to crystal form transformation; mixing the modified industrial aluminum hydroxide with a solvent to obtain first slurry; adjusting the pH value of the first slurry to a set pH value; performing hydrothermal treatment on the first slurry with a set pH value to obtain second slurry; adjusting the solid content of the second slurry to a set solid content; aluminum salt is added into the second slurry with the set solid content, and third slurry is obtained; sequentially freezing and freeze-drying the third slurry to obtain a frozen compound; the frozen compound is sequentially subjected to first heating in a non-oxidizing atmosphere and second heating in an oxidizing atmosphere, and the aluminum oxide aerogel is obtained. Therefore, the invention provides a novel preparation method of the aluminum oxide aerogel.

The invention discloses a magnesium ion-containing water-alcohol mixed electrolyte and application, the electrolyte comprises a solvent, magnesium salt and an additive, the solvent is a mixed solvent of water and alcohol organic matters, the additive is water-soluble carboxylic acid, and the volume molar concentration of the additive is 0.01-2 mol / L. The electrolyte has a wide electrochemical stability window and high ionic conductivity, the adopted raw materials are safe and easy to obtain, the preparation method is simple, the cost is low, and large-scale batch production is facilitated. The electrolyte is applied to a secondary battery containing magnesium ions.

The invention discloses a spicy beef paste and a preparation method thereof, and belongs to the technical field of food processing, the beef paste comprises the following raw materials: soybean oil, diced beef or beef stuffing, high-alcohol-content white spirit, sweet soybean paste, spicy crushed dry chili powder, pepper paste, cooked white sesame, soft white sugar, fistular onion stalk and the like. The preparation method comprises the steps of high-temperature fragrance excitation, dehydration and fishy smell removal, medium-temperature material frying, low-temperature long-time boiling, post-seasoning and the like, and by accurately controlling the oil temperatures (180-200 DEG C, 80-90 DEG C and 50-60 DEG C) of different stages and the material adding sequence, the technical problems that traditional beef paste is dry and astringent in beef, not thick in sauce flavor, spicy but not fragrant and short in shelf life are effectively solved. The prepared beef paste is mellow in meat quality, spicy, fresh and fragrant, strong in layering sense and relatively good in storage stability.

The invention discloses freeze-dried powder for an ice glaze preparation, the ice glaze preparation and a use method of the ice glaze preparation. The preparation method of the freeze-dried powder for the ice glaze preparation comprises the following steps: step 1, collecting snakehead mucus; and step 2, removing impurities from the collected snakehead mucus, carrying out micron filtration on the impurity-removed liquid to obtain a filtrate, and carrying out freeze-drying operation on the filtrate to obtain freeze-dried powder. And dispersing the obtained freeze-dried powder in deionized water, centrifuging, taking the supernatant, and cooling to obtain the ice-coated preparation, the mass percentage of the freeze-dried powder in the ice-coated preparation being 0.2-2.5 wt%. The ice glaze preparation prepared from the freeze-dried powder is low in water activity, can reduce the water vapor partial pressure of the inner layer and the surface layer of fish, reduces the pressure difference between the water vapor on the surface layer of the fish and the water vapor in air in a freezing chamber, and inhibits ice crystal sublimation; the ice glaze preparation can inhibit the growth of ice crystals, improve the swelling phenomenon of the ice glaze, and prevent the ice glaze from releasing more expansion pressure when the ice glaze is frozen.

The invention provides a preparation method of fructo-oligosaccharide, and belongs to the technical field of fructo-oligosaccharide synthesis. The method comprises the following steps: (1) preparing a reaction stock solution; (2) adding fructosyl transferase into the reaction stock solution, and then carrying out constant-temperature water bath reaction; supplementing the sugar solution in the reaction process to continue the reaction to obtain a first-process saccharified solution; (3) filtering the first-process saccharification liquid by adopting a semi-permeable membrane to obtain trapped fluid and filtrate; (4) performing a constant-temperature water bath reaction on the filtrate to obtain a second-process saccharification liquid, and then mixing the second-process saccharification liquid with the trapped fluid to obtain a fructo-oligosaccharide crude liquid; (5) carrying out decoloration, desalination, chromatographic separation, evaporation concentration and drying on the fructo-oligosaccharide crude liquid to prepare fructo-oligosaccharide powder; the reaction time is shortened, the utilization rate of fructose is increased, generation of kestose in a system is promoted, the content of kestose in fructo-oligosaccharide is increased, and the water activity of fructo-oligosaccharide is reduced.

The application relates to the field of welding technology, and particularly discloses a water-soluble flux and a preparation method thereof. The water-soluble flux comprises the following raw materials in parts by weight: 6-12 parts of a borate ester covalent activator; 3-8 parts of cucurbituril hydrate; 0.01-2 parts of an inhibitor; 1-3 parts of a modified graphene quantum dot solution; 1-5 parts of a cyclic ether solvent; 0.5-2 parts of a metal-organic framework material containing mercapto groups; and 68-88.5 parts of deionized water. The modified graphene quantum dot solution is obtained by modifying graphene quantum dots with dioctadecyldimethylammonium chloride. The flux of the application can effectively solve the problem of water residue in the later stage after the activator is decomposed and volatilized in the early stage of welding by combining the water-soluble flux with the cyclic ether solvent, thereby reducing the problems of virtual welding, bubble defects and the like of the welding points, and effectively improving the strength and reliability of the welding points.

The invention discloses a paracetamol tablet and a preparation method thereof, and belongs to the technical field of pharmaceutical preparation preparation. By weight, the paracetamol tablet includes 86.88 parts of paracetamol, 4.52 parts of adhesive, 2.90 parts of disintegrant, 5.21 parts of filler and 0.49 parts of lubricant. The present invention reduces the types and amounts of auxiliary materials by improving the formula of paracetamol tablets and combining a special preparation process, and the main drug accounts for a high proportion. At the same time, the preparation process is simple, the production cost is low, and the production is safe. It does not require boiling water or organic solvent slurrying, and the degree of mechanization is high. It is suitable for industrial production, solves the problem of poor compressibility of paracetamol tablets, and the prepared paracetamol tablets are small in weight, which can minimize the management and inspection costs of auxiliary materials, improve the compliance of patients with medication, and the product quality is stable, the dissolution is complete, the quality is consistent with the original preparation, and it does not contain surfactants, which meets the BE exemption requirements of the consistency evaluation of generic drugs of the State Food and Drug Administration.

This invention belongs to the field of dairy goat feed technology, specifically relating to a total mixed ration (TMR) for dairy goats containing fresh oat hay, its preparation method, and its application. The invention involves chopping fresh oat hay, sequentially spraying it with a functional oil-based compound emulsion and an organic acid salt compound preservative solution, followed by static adsorption and mixing treatment, and then gradient mixing with dry-based raw materials to obtain the TMR. This invention is the first to achieve the direct use of high-moisture fresh oat hay in TMR without fermentation. It utilizes the cell wall fiber network of fresh oat hay as a natural carrier for functional oils, allowing the oils to penetrate into the fiber pores through static adsorption, forming a stable physical encapsulation structure and effectively reducing the rumen hydrogenation rate of polyunsaturated fatty acids. The invention employs a low-starch, high-slow-release fiber gradient energy supply design, combined with the organic acid salt compound preservative solution, to achieve synergistic effects in feed preservation, oil protection, and rumen health regulation.

The invention relates to the technical field of preparation of processed cheese, in particular to collagen casing-wrapped processed fish cheese easy to store at normal temperature and a preparation method of the collagen casing-wrapped processed fish cheese. Comprising the following components in parts by weight: 1000-1200 parts of cheese, 10-20 parts of cream, 70-150 parts of minced fish, 80-120 parts of protein powder, 35-50 parts of emulsifying salt, 5-20 parts of a compound stabilizer, 340-500 parts of water and 0.2-2 parts of lactic acid. The preparation process comprises the steps of chopping and mixing, heating and shearing, sterilizing, sausage filling, integrated treatment and gas filling and packaging, and the obtained product has a special flavor, is fine and smooth in taste and can be stored at normal temperature. The product storage conditions are improved while the flavor and taste of the product are improved, and the problems that the fish cheese product in the prior art is single in flavor, rough in taste, not fine enough, not easy to store at normal temperature and the like are solved.