Researches On Physicochemical And Processing Properties Of Pteridium Aquilinum Starch

Systematically research on Pteridium aquilinum starch has been done in these experiments. The raw materials Pteridium aquilinum were collected in Zhuzhou and Pteridium aquilinum starch was extracted by using a traditiohal wet-milling process. The nutrients were determined by some ordinary physicochemical analyses. Granular properties and gelatinizing properties were studied by using advanced instruments including X-ray diffractometer, scan electronic microscope, DSC and polarizing-microscope. Also, paste properties and retrogradation properties were investigated in the experiments. The results are as following:Nutrients in Pteridium aquilinum starch were 13.87% of water, 82.30% of starch, 0.45% of crude protein, 0.23% of fat and 0.40% of ashesThe granular size of Pteridium Squilinum starch was not even. It ranged from 4.6 um to 24.3 um. The average was 11.9 um. The granule was spheric, nephric and polygonal in shape. It had a polarizing cross. The majority showed a cross shape, and the minority showed an "X" shape at the center of the granules. The crystalline pattern of Pteridium Squilinum starch was C type. The crystallinity was 38.71%. The relative density was 1.49, lower than that of maize starch and higher than that of chestnut starch. The whiteness of Pteridium aquilinum starch was 67.The solubility of Pteridium Squilinum starch and swelling power increased with the temperature raise. The solubility was 19% and the swelling power of Pteridium Squilinum starch was 49% at 95℃.The swelling power was small below 65℃ and was enhanced quickly above 70℃, which can be classified as two-phrase swell and restricting swell.Gelatinization temperature of Pteridium Squilinum starch was 57-64-74℃ determined by polarizing-microscope; and gelatinization temperature was 57.50-65.54-70.30℃, AT was 12.80℃ and enthalpy was 9.65J/g determined by the instrument of DSC.Viscosity of Pteridium Squilinum paste was 6.387 mPa·s, 0.93 times of that of potato starch and 1.5 times of that of maize starch. Its heat stability was better than that of potato. With the increase of concentration, the viscosity of paste was stronger.