| In order to produce microporous starch, the best craft parameter and path were studied as well as the affects of acid hydrolysis treatment and enzyme hydrolysis treatment on the formation of microporous starch from maize starch. Sequently, the surface properties, physicochemical properties of the starch granules after treatment were studied by means of SEM. Finally, the applying of microporous starch as a microporous matrix material adapt for absorption, absorbed water-soluble functional compositions and oil-soluble functional compositions had also been studied in this paper. The results indicated:(1) The optimum parameters in using acid hydrolysis method to produce microporous starch process: The main factor that affects hydrolyzation is the density of the hydrolysis acid > reaction time > reaction temperature. By means of SEM ,the best reaction term was confirmed as the density of hydrochloric acid 6%,reaction temperature 50 C, reaction time 18h.In this condition, the pore size and depth is right and even onto the starch granule.(2) The optimum parameters in using single enzyme hydrolysis method to produce microporous starch process were studied respectively, such as reaction temperature, reaction time, enzyme dose and pH. And the experiment selected three kinds of enzyme just as glucoamylase, a -amylase and promozyme to treat starch granule. The functional efficiency of single enzyme treatment is glucoamylase>a -amylase>promozyme.(3) The optimum parameters in using compound enzyme hydrolysis method to produce microporous starch process: The functional efficiency of compound enzyme treatment is glucoamylase: a -amylase > glucoamylase: promozyme > a -amylase: promozyme. The efficiency of compound enzyme treatment is better than the single enzyme by SEM, porosity increased after compound enzyme treatment in proportion of 1.0-3.0.But when the proportion enlarged to the 4.0 or above, some piece of the segment flaked from the starch granule, even found the collapse of the starch structure. All in all, the proportion ofglucoamylase and a -amylase 1.0-3.0 is proper.(4) The physicochemical character of microporous starch were studied systematically compared with the native starch: Microporous starch has better stability of viscosity, lower retrogration, better freeze-thaw stability and higher clarity. And in the absorption experiment with water or oil, the ratio of absorption is higher than the native starch's.(5) The applying character of microporous starch were studied compared with native starch and B-CD. The results indicated microporous starch has better absorption ability of water-soluble functional compositions than the others, but has lower absorption ability of oil-soluble functional compositions compared with the B-CD .In the storing experiment, the absorption ability of microporous starch is stable. It effectively reduced the loss of Vitamin C, lowed oxidation of Salad oil.
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