Studies On The Production And Application Of Japonica Porous Starch And Modified Starch

Porous starch, a new type of modified starch, has various advantages as a kind of absorbent with high efficiency, innocuity and safety. It can be widely used in many industries, including food, dairy industry and hygienic, and is becoming a study hotspot. Japonica rice starch is used as material to prepare for porous starch, which is new product in the world. Japonica rice starch is suitably cross-linked and then partially enzymolysised to prepare porous cross-linking starch with restraining swell. Then rice porous starch was applied to foundation make-up and corn porous starch was used to prepare IPSX to adsorb Cu2+. The results of this study are not only good for the expanding the applications of japonica rice starch and porous starch, but also beneficial for the promotion of modifying research of porous starch. The main contents and results are described as follows:Sodium hydroxide was used to remove the protein in the Japonica rice starch. By using step optimization, the optimum conditions were: under the room temperature, 0.4% (g/mL) NaOH, extracting time 4h and ratio of rice to NaOH solution 1:3(g/mL). And then the best technique conditions of producing porous starch were obtained by orthogonal test which were temperature 30℃, reaction time 8h, pH 4.0, ratio of glucoamylase toα-amylase 12:1, ratio of starch to buffer 50:100, quantity of complex enzyme with theoretically hydrolyze 30% of raw starch.The porous starch was further modified by cross-linking. The cross-linking optimum conditions were obtained by single factorial experiment and the orthogonal experiment: 0.8% (of the raw starch) sodium trimetaphosophate, pH 10, the temperature 40℃, reaction time 210min. And main factors which influence the cross-linking porous starch were decided by two-level orthogonal design, then the optimum conditions were obtained with RSA experiment: reaction time 11h, solid concentration 50%, ratio of glucoamylase:α-amylase 10:1.The fuzzy synthetic evaluation was applied to evaluate the effect of 2 kinds of starch in foundation make-up: The results showed that cross-linking porous starch was the best one.Physical properties of the above 4 kinds of starch, raw rice starch, porous starch, cross-linking starch and porous cross-linking starch, were studied comparatively. The results showed that the properties, including anti-swelling, water-holding capacity, frozen-thaw stability of cross-linking starch were better than those of raw starch and porous starch. And the properties (transparency and contrastive volume) of cross-linking porous starch were more excellent than those of cross-linking starch.A kind of another modified starch, ISX, was synthesized by corn porous starch, which could absorb heavy metal ion of wastewater. The synthesis of ISX was gained by orthogonal test: porous starch 15g, Epichlorohydrin 0.4 mL, CS2 4.5mL, reaction time 2h, MgCl2 5g.The optimal adsorption conditions to Cu2+ of ISX were that 177.2 mg ISX, adsorption time 10min, pH4.0. After adsorption, the concentration of Cu2+ was changed from 26.38μg/mL to 1.01μg/mL.