Research On Pore Starch Preparation By Magnetic Fossilization Amylase

Porous starch is a modified starch hydrolyzed by amylase under the gelatinizationtemperatures. Microporous starch has a certain mechanical strength and good adsorptionproperties, Therefore, microporous starch can be used as adsorbent material orembedding medium. As an absorbent, porous starch due to an efficient, non-toxic, safetyfeatures is widely used in food, medicine, paper making, chemical industry. The productdevelopment can greatly improve the absorption of the industrial production of porousstarch.Using sweet potato starch as raw materials, we work in the following aspects:1. Using a variety of test methods for the selection of glucoamylase immobilizedcarrier. According to the nature of the carrier with immobilized glucoamylase catalyticmechanism, we select three fixed-based carriers (the magnetic response of chitosan, themagnetic response of the polyvinyl alcohol, amino-silanized magnetic particles),Conditions and the nature of the immobilized enzyme was researched. The results showthat the magnetic PVA immobilized enzyme activity, mechanical strength andoperational stability are the best.2. Immobilized in magnetic polyvinyl alcohol as a carrier, the immobilized enzymepreparation conditions were researched. By studying the enzyme concentration,glutaraldehyde concentration, pH, temperature fixed time and fixed-based single-factorexperiments and orthogonal experiment, the optimum extraction conditions were shown:Enzyme concentration of3.0mg/ml,6.0%glutaraldehyde, immobilization temperatureof45℃, immobilization time of4h, pH7.5. In this process under the conditions of theimmobilized enzyme activity significantly increased and the relative maximum, that is88.5%.3. Preparation of magnetic immobilized microporous starch process optimization.The porous starch preparation process was determined by single factor experiments andorthogonal test. Experiments show that: the pH and the amount of immobilizedenzyme preparation of microporous starch have a greater impact, in order to obtain theadsorption properties of porous high-starch, the optimum conditions: the amount ofimmobilized enzyme was2.0%, reaction time15h, the pH is4.5, the reactiontemperature is35℃, the oil absorption rate of67.52%.4. In the process of fermentation preparation of microporous starch, feeding andincubation time influences the oil absorbency apparently. Under conditions of inoculum concentration2.0%, feeding and incubation time60h, rotate speed100r/min, feedrate10%, the high oil absorbency rate (54.88%)is still lower than magnetic immobilizedmicroporous starch process’s(67.52%).5. Microwave-assisted preparation of microporous starch processing enzymeimmobilization. The study found that ultrasonic power and stirring speed onmicroporous starch oil rate impact, ultrasonic time and stirring speed of the interactionof micro-oil yield of starch is also more significant. Optimum conditions: stirringpowerof145W, ultrasonic time of31.9min, stirring speed166r/min. Based on the aboveoptimized experimental conditions, the measured oil absorption rate of79.3%.