| This paper mainly focused on the production process, characteristics and applications of porous starch which was made from maize starch, potato starch, rice starch respectively.During the production process of porous starch, the best technical parameter and path were studied as well as the affects of acid hydrolysis treatment and amylase hydrolysis treatment on the formation of porous starch; Sequent, the surface properties, physicochemical properties of the starch granules after treatment were studied by means of SEM, and discuss the mechanism of porous reformation. Finally, the applying of porous starch as a porous matrix material adapt for absorption, absorbed Carmine pigment, Vitamin C and Salad oil functional compositions had also been studied in this paper. The results indicated:1. Using SEM observed porous starch which was made from maize starch, potato starch and rice starch respectively, the results show that the best effect of porous reformation with maize starch.2. The process of maize porous starch formation was studied, through observing the inner and outside appearance of the maize porous starch during different stages of hydrolyzed, discovered that the role of amylase order: amylase hydrolyzed the surface of starch granules at first, and then hydrolyzed the starch granules as holes, these holes extended to the center of starch granules, and then from the center to start the hydrolysis of starch granules, starch granules will eventually form an internal cavity. Starch granules would be broken into scattered debris as hydrolysis continued.3. During the production process of porous starch by hydrochloric acid and complex amylase, oil adsorption ratio was used as an index to evaluate the porous starch. Based on single factor and orthogonal experiment design, optimal conditions of porous starch production by amylase were obtained: the ratio of glucoamylase and a-amylase 4 : 1, hydrolysis time 16h, soluble solid concentration 30%, hydrolysis temperature 45℃, quantity of complex enzymes added 0.8%(w/w), oscillation speed 60 r/min; The optimal conditions of porous starch production by hydrochloric acid were obtained: hydrolysis temperature 40℃, 6% concentration of hydrochloric acid solution, hydrolysis time 12h and soluble solid concentration 30%.4. Study on the physical properties of porous starch. Compared with the natural starch, the results indicated porous starch had better absorption ability of functional compositions than the other, the solubility, expansibility, specific volume and light transmission rate increase, the settlement volume decreases; Porous starch was detected by DSC and XRD, observed by polarization microscope, found that the crystalline structure of porous starch have not been destroyed, that means amylase hydrolyze the non-crystalline regions of starch granules at first, however, damaged the crystallization regional of the starch granules slightly, porous starch still has integrity crystal structure and certain particles strength.5. Study on the adsorption properties of porous starch. Appling porous starch adsorption Carmine pigment experiments obtained porous starch in 140min reaching saturation adsorption capacity; Porous starch to Carmine pigment and Vitamin C saturation adsorption capacity were 33 mg/g, and 30 mg/g respectively; Vitamin C and salad oil were embedded by porous starch, oxidation rate decreased significantly; Porous starch could delay the release of salad oil losses.
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