Abstract: Disclosed are an agarase mutant with improved thermal stability and application thereof, belonging to the fields of genetic engineering technology and enzyme engineering. The present disclosure provides an agarase mutant, which is obtained by mutating the amino acid at the 86th site, the 373rd site, the 374th site, the 496th site, the 507th site, or the 747th site of agarase with an amino acid sequence as shown in SEQ ID NO.1. The agarase mutant provided by the present disclosure improves the thermal stability and the hydrolytic activity of the agarase. Compared with the wild type enzyme, the mutant enzyme shows excellent heat resistance and can be industrially used at a relatively high temperature, so that the utilization rate of agar raw materials and the yield of oligosaccharides from agar are improved, and the mutant enzyme has a good industrial application prospect.

Abstract: Disclosed are a protective starch-based film and its preparation method and application, belonging to the field of food packaging. According to the method for preparing the protective starch-based film, surfaces of zinc oxide nanoparticles are enabled to adsorb tannic acid and iron ions under the action of metal coordination by controlling the pH to obtain metallic polyphenol network coated zinc oxide nanoparticles, dispersion of the obtained nanoparticles is added to a starch gelatinization solution, and a melanin-like precursor is simultaneously added to form mixed liquid; and by controlling the pH of the mixed solution, ?-? stacking, self-polymerization and metal coordination are induced, so that a stable protective starch-based film with a nano-reinforced interpenetrating network structure is formed.

Abstract: The present disclosure discloses a simple preparation method of green acid-modified cyclodextrin, belonging to the field of cyclodextrin modification. Cyclodextrin and succinic acid are mutually modified by an esterification reaction in the presence of catalyst, and acid-modified cyclodextrin with different modification degrees is obtained by controlling reaction time at a high temperature or under a microwave action. The prepared modified cyclodextrin does not involve the use of toxic and harmful reagents, the modification reaction is simple, green and controllable, and the loading capacity of the modified cyclodextrin to guest molecules is remarkably improved compared with the loading capacity of the original cyclodextrin, so that the modified cyclodextrin has great application potential in the health fields such as food, medicines, and cosmetics.

Abstract: Disclosed are a protective starch-based film and its preparation method and application, belonging to the field of food packaging. According to the method for preparing the protective starch-based film, surfaces of zinc oxide nanoparticles are enabled to adsorb tannic acid and iron ions under the action of metal coordination by controlling the pH to obtain metallic polyphenol network coated zinc oxide nanoparticles, dispersion of the obtained nanoparticles is added to a starch gelatinization solution, and a melanin-like precursor is simultaneously added to form mixed liquid; and by controlling the pH of the mixed solution, ?-? stacking, self-polymerization and metal coordination are induced, so that a stable protective starch-based film with a nano-reinforced interpenetrating network structure is formed.

Abstract: The present disclosure discloses a simple preparation method of green acid-modified cyclodextrin, belonging to the field of cyclodextrin modification. Cyclodextrin and succinic acid are mutually modified by an esterification reaction in the presence of catalyst, and acid-modified cyclodextrin with different modification degrees is obtained by controlling reaction time at a high temperature or under a microwave action. The prepared modified cyclodextrin does not involve the use of toxic and harmful reagents, the modification reaction is simple, green and controllable, and the loading capacity of the modified cyclodextrin to guest molecules is remarkably improved compared with the loading capacity of the original cyclodextrin, so that the modified cyclodextrin has great application potential in the health fields such as food, medicines, and cosmetics.

Abstract: The disclosure relates to a preparation method of a amylodextrin and belongs to the technical field of starch chemical modification. According to the method, de-clustering and complexation effects of ultrasonic waves are used to achieve de-clustering of a starch chain and complexation of an amorphous region and an emulsifier, and then ?-amylase and pullulanase are used to achieve complex enzymolysis. Because the amorphous region and the emulsifier form a complex which is resistant to enzymolysis, the amorphous region is prevented from being destroyed. Finally, dextrins of different molecular weights are separated by a membrane separation method, so as to obtain a amylodextrin product with low polydispersity coefficient and narrow molecular weight distribution, and the starch comprehensive utilization efficiency is increased to 70% or above.

Abstract: The present disclosure discloses a preparation method of low-glycemic index slowly digestible starch-based reconstituted instant rice, and belongs to the technical field of food processing. The preparation method is based on high-temperature fluidization technology to carry out non-crystallization treatment on a solid phase broken rice raw material in a short period of time, and then the material is subjected to a one-step reactive extrusion technology combining enzymatic hydrolysis and esterification treatment to prepare the reconstituted instant rice with high content of slowly digestible starch and low glycemic index. The reconstituted instant rice prepared by the one-step molding extrusion technology is suitable for type II diabetes patients to eat, and at the same time increases the added value of agricultural and sideline products, reduces production cost, and improves production efficiency.

Abstract: The disclosure provides a modified cyclodextrin/mesoporous silica for adsorbing Pb and Cd and application thereof, belonging to the technical field of adsorbent materials. By using surface modification, chloroacetic acid is used as anions, and a modified cyclodextrin is grafted onto a surface of a cyclodextrin/mesoporous silica by nucleophilic substitution to prepare the modified cyclodextrin/mesoporous silica adsorbent material. The modified cyclodextrin/mesoporous silica adsorbent material prepared in the disclosure has the advantages of simple preparation method, strong adsorbability, easy separation, good biocompatibility and the like. When the material is used as an adsorbent to adsorb heavy metal ions Pb2+ and Cd2+, maximum removal rates can reach 97.8% and 81.29% respectively. Therefore, the material has wide application prospects in removal of heavy metals in sewage and the like, thereby improving the water environment that people depend on for survival.

Abstract: The disclosure discloses a preparation method of slowly digestible starch, and belongs to the technical field of starch modification. In the disclosure, ordinary rice starch and corn starch are used as raw materials, and the starch is fully de-clustered through dry-heat amorphization treatment, instead of traditional hydrothermal gelatinization; then ultrasonic treatment is used to induce complexation of amino acids and starch milk to form VI-type crystal; and finally through an extrusion technology, the VI-type crystal is transformed into VII-type crystal, and the content of the slowly digestible starch is significantly increased to 55%-60%. The disclosure is highly efficient, simple and environmentally friendly, and the prepared product can be used as a drug sustained-release carrier or a low-glycemic index food ingredient, and has important practical value for the regulation of chronic diseases such as diabetes and cardiovascular diseases.

Abstract: The present disclosure discloses a production method of normal-temperature instant cooked rice and belongs to the technical field of food processing. The method of the present disclosure comprises the main steps of rice washing and soaking, flavor blending, sub-packaging, cooking, sterile vacuum sealing, cooling and crystallization and normal-temperature storage, wherein an aqueous solution containing flavor substances is adopted to perform flavor blending, and a fast cooling mode is adopted to perform cooling and crystallization. The normal-temperature instant cooked rice obtained through the production method provided in the present disclosure can keep the original flavor after being stored for 90 days.

Abstract: A method for screening adulteration of fibrate anti-hyperlipidemia chemicals in tea by combined method of high performance thin layer chromatography (HPTLC) and bioluminescence, which belongs to the field of food inspection. The method includes: firstly, formulating standard solutions of bezafibrate and ciprofibrate, and preparing a tea sample; pre-washing a thin-layer plate and then performing HPTLC spotting; performing HPTLC separation to move original mixed target objects mixed originally onto different positions of the thin-layer plate according to different molecular structures, so as to form a physical isolation; and subsequently, simultaneous detection of multiple targets in the tea sample could be realized conveniently through luminous bacteria coupled with the thin-layer plate by an immersed manner.

Abstract: The disclosure discloses a preparation method of slowly digestible starch, and belongs to the technical field of starch modification. In the disclosure, ordinary rice starch and corn starch are used as raw materials, and the starch is fully de-clustered through dry-heat amorphization treatment, instead of traditional hydrothermal gelatinization; then ultrasonic treatment is used to induce complexation of amino acids and starch milk to form VI-type crystal; and finally through an extrusion technology, the VI-type crystal is transformed into VII-type crystal, and the content of the slowly digestible starch is significantly increased to 55%-60%. The disclosure is highly efficient, simple and environmentally friendly, and the prepared product can be used as a drug sustained-release carrier or a low-glycemic index food ingredient, and has important practical value for the regulation of chronic diseases such as diabetes and cardiovascular diseases.

Abstract: The disclosure relates to a preparation method of a amylodextrin and belongs to the technical field of starch chemical modification. According to the method, de-clustering and complexation effects of ultrasonic waves are used to achieve de-clustering of a starch chain and complexation of an amorphous region and an emulsifier, and then ?-amylase and pullulanase are used to achieve complex enzymolysis. Because the amorphous region and the emulsifier form a complex which is resistant to enzymolysis, the amorphous region is prevented from being destroyed. Finally, dextrins of different molecular weights are separated by a membrane separation method, so as to obtain a amylodextrin product with low polydispersity coefficient and narrow molecular weight distribution, and the starch comprehensive utilization efficiency is increased to 70% or above.

Abstract: A carbon skeleton reinforced porous starch and a preparation method thereof. The method of preparing the porous starch includes bonding starch to transition metal ions, then treating the starch attached with the transition metal ions and amylase via an extruding device, and finally forming a starch-based porous material having a high strength recombination structure, that is, the carbon skeleton reinforced porous starch.

Abstract: The present disclosure discloses a rice conditioning process and a production method of instant rice, and belongs to the technical field of food processing. According to the present disclosure, rice conditioning pretreatment is realized on the basis of an instantaneous high-temperature fluidization technology, and a conditioning liquid containing compounded soft rice flour, edible oil and rice soup is prepared through a rice soup backfilling technology. A technology of rapid cooling for film forming is adopted to increase a water-retaining film on the surface of rice, so as to enhance the water-retaining property, viscoelasticity and luster of the rice. The method mainly includes the steps of rice washing and draining, conditioning, cooking, aseptic packaging and rapid cooling for film forming. According to the present disclosure, industrialized continuous production can be realized, and the obtained instant rice is sticky but not adhesive after being stored for 60 days, and has a good taste.

Abstract: The disclosure discloses a preparation method of rice noodles with low glycemic index, and belongs to the technical filed of food processing. According to the disclosure, by adding debranching enzymes and an emulsifying agent into rice starch, resistant starch is prepared and obtained through one-step extrusion, and then, other food raw materials are compounded to form the low glycemic index rice noodles through secondary extrusion. By using the characteristic that V-type crystals are formed by complexing the emulsifying agent and amylose, the disclosure adds the debranching enzymes and the emulsifying agent into a rice starch raw material for extrusion processing. The debranching enzymes added in a first-step extrusion processing process perform limited hydrolysis on starch to reduce starch branching and improve a content of the amylose.

Abstract: The present disclosure discloses a preparation method of low-glycemic index slowly digestible starch-based reconstituted instant rice, and belongs to the technical field of food processing. The preparation method is based on high-temperature fluidization technology to carry out non-crystallization treatment on a solid phase broken rice raw material in a short period of time, and then the material is subjected to a one-step reactive extrusion technology combining enzymatic hydrolysis and esterification treatment to prepare the reconstituted instant rice with high content of slowly digestible starch and low glycemic index. The reconstituted instant rice prepared by the one-step molding extrusion technology is suitable for type II diabetes patients to eat, and at the same time increases the added value of agricultural and sideline products, reduces production cost, and improves production efficiency.

Abstract: The present disclosure disclosed is a preparation method for low glycemic index resistance starch recombinant rice, which belongs to the technical field of food. The method of the present disclosure is as follows: after starch and lipid in an alcohol aqueous system are complexed under low temperature, variable-temperature crystallization is performed, so that a low glycemic index resistance starch is prepared, and then, with the low glycemic index resistance starch as a main material, low glycemic index recombinant rice is prepared by the extrusion technique. The low glycemic index resistance starch prepared by utilizing the method of the present disclosure has the functions of controlling postprandial blood glucose, protecting and transporting fatty acid, retarding starch retrogradation and so on. The low glycemic index recombinant rice prepared by utilizing the method of the present disclosure is suitable for being eaten by patients with type II diabetes.

Abstract: The present invention discloses a multi-series continuous-flow magnetoelectric coupling processing system and applications thereof. The processing system comprises multi-series of induction units, a power supply and a feed liquid container, wherein each series of the induction unit comprises a closed iron core, a primary coil wound around one side of the closed iron core, and a secondary coil wound around the other side of the closed iron core and arranged in an induction cavity, the secondary coil comprises an insulation pipe for circulation of feed liquid, and the two ends of the insulation pipe are exposed from the induction cavity and are respectively acted as a feeding hole and a discharge hole; the power supply is in parallel connection with each primary coil in the induction unit and provides excitation voltage to each primary coil; and the feed liquid container is in series connection with the insulation pipes of the multi-series induction units to form a feed liquid circulation loop.

Abstract: The present disclosure discloses a production method of normal-temperature instant cooked rice and belongs to the technical field of food processing. The method of the present disclosure comprises the main steps of rice washing and soaking, flavor blending, sub-packaging, cooking, sterile vacuum sealing, cooling and crystallization and normal-temperature storage, wherein an aqueous solution containing flavor substances is adopted to perform flavor blending, and a fast cooling mode is adopted to perform cooling and crystallization. The normal-temperature instant cooked rice obtained through the production method provided in the present disclosure can keep the original flavor after being stored for 90 days.