Studies On The Enzymatic Preparation And Application Of Microporous Starch

Microporous starch is a kind starch granules of contain some micropore, It isproduced in physical and chemical method or enzymatic digestion. Microporousstarch has excellent adsorption properties, It can preserve volatile substances ofphotolysis, volatile, easy oxidation,and has been applied to slow release material, oradsorb peculiar smell of some material. In this paper, we study the preparationtechnology and optimize the preparation conditions of porous starch. we compared thedifference of microporous starch and starch. Microporous starch was studied inslow-release effect of magnesium chloride. The main results as follows:1) The microporous starch was obtained by hydrolysis reaction of complexenzyme. Using single factor experiment. We researched the influence of enzymesolution temperature, ratio of enzyme, quantity of enzyme, chroma of substrate, buffersolution pH and reaction time to oil absorption. We got the best technologicalconditions: enzyme solution temperature50℃, enzyme ratio was4:1, quantity ofenzyme was2%, the substrate quantity chroma was0.14g/ml, buffer solution pH was4, the reaction time was8h.2) On the basis of single factor experiment，we screened4factors of enzymesolution temperature(A), buffer solution pH(B), quantity of enzyme(C), enzymeratio(D). The regression equation was obtained by Box-behnken response surface test.We got the best process parameters: enzyme solution temperature was50.19℃, buffersolution pH was4.5, quantity of enzyme was1.86%, enzyme ratio was3.16.Predictive value of oil adsorption rate was102.684%, This result was proved reliableby the actual operation.3) we analyzed the change of the crystalline structure of starch granules,,gelatinization temperature, micro structure and functional groups by X-ray diffractionanalyzer, iodine-starch colorimetric method, differential scanning calorimetryapparatus, optical microscope, scanning electron microscope (sem) and Fourier transform infrared spectrometer. We concluded that the crystalline structure ofmicroporous starch did not change compared with potato starch; The gelatinizationtemperature of potato starch was62.6℃, the gelatinization temperature of potatostarch was65.7℃; Microporous starch has cracks and gaps at the observation ofoptical microscope, and has holes and pits at the observation of scanning electronmicroscope; Microporous starch’s characteristic absorption peaks on the graph ofinfrared spectrum didn’t change compared with potato starch, This suggests thatfunctional groups didn’t change.4) By single factor test and orthogonal test, We got the best technologicalconditions of microporous starch adsorp magnesium chloride: The concentration ofmagnesium chloride solution was0.15g/ml, adsorption temperature was40℃, mixingtime was50min. The magnesium chloride adsorption rate of microporous starch was5.87%. The experiment protein coagulation showed that microporous starch hasslow-release effect to the magnesium chloride...