| Having exploited the porous corn starch as material in this dissertation and adopted ethanol alkaline and ultrasonic method for processing of porous starch. The best technical parameters for preparing Granular cold-water-soluble starch were determined by the reference standard of solubility in cold water. Utilizing modern instruments analysis and technologies, the author has studied the function and physical and chemical properties of the products which had been made before, meanwhile having made it as the core material for preparing micro-capsules of Zanthoxylum bungeanum essential oil and tested the stability of it besides applied it practices. Main results achieved in this research as follows:(1)The best technical parameters for preparing Granular cold-water-soluble starch were determined by experiments. The optimal technical conditions for preparing by ethanol-alkaline method were:Having weighed 10g of porous starch (dry basis) in the beaker and added 100 mL ethanol that volume fraction was 80%, the NaOH dosage was 4.8g, the reaction time was 20min, the reaction temperature was 40℃, the solubility was higher than any other conditions at this time, which could reach 77.4%. The optimal technical conditions for preparing by ultrasonic-assisted method were:Having weighed 10g of porous starch (dry basis) in the beaker and added 100 mL ethanol that volume fraction was 80%, the NaOH dosage was 4.5g, the power of ultrasonic was 50W, the reaction time was 10min, the solubility was higher than any other conditions at this time, which could reach 75.(2) Having observed by the microscope polarizing, the polarized crosses of Granular cold-water-soluble corn starch have disappeared by and large. The result indicated that the order structures of starch granules have been changed significantly after ethanol-alkaline treatment. It could see directly that the structures of corn granules starch were basically full-formed by electron microscopy scanning and have kept the original form of corn starch granules, whereas it was lager than the original starch granules and adhesion were appeared between granules, besides, there were large pressions and holes on the surface of the granules. By the X-ray diffraction analysis, it founded that the Granular cold-water-soluble starch was the V-type sicp which combined crystal with submicroscopic crystal structure, the reaction occurred in the amorphous region of the particles and the crystalline structure of particles were destroyed in the reaction, so the features of crystal structure have been lost basically.(3)The surface viscosity of cold water soluble porous starch has increasing with the rising temperature, but at the same temperature it was lower than the original porous starch and the corn starch; the acidoresistance of granular cold water soluble porous starch was good, while alkali stability was poor; the shear rate was in the range of 0.3-1.5r/mim the surface viscosity of Granular cold-water-soluble starch had a sharp decline, there was unconspicuous influence when the shear rat increased, the water absorption has decreased greatly when the freezing and thawing increased of Granular cold-water-soluble starch, the stability Of freezing and thawing has improved significantly; but the shearing resistance of Granular cold-water-soluble corn starch was relatively poor while the transparency was good, and with the increasing concentration of starch paste presented a rising trend, the retrogradation property of Granular cold-water-soluble starch was choiceness.(4)Porous starch and cold water soluble granular starch adsorption properties of porous flat, and maintained the adsorption properties of porous starch; in vitamin C and the stability of salad oil adsorption experiments, it can greatly slow down the absorption of material conditions of contact with the outside world, play to extend the shelf-life and slow-release effect.(5)With a simple method of rapid preparation of the porous starch granules cold water soluble powder encapsulated pepper oil, pepper oil found its adsorption capacity and the embedding is much higher than the original starch; tests show that the adsorption of its volatile oil content with time can still maintain a high level, indicating that it can to protect and release the role of pepper oil. The preparation of cold water soluble granular starch encapsulated porous powder pepper essential oils to add in the soup, we found that cold water soluble granular starch microcapsules porous pepper oil in a short period of time the prompt release, make up the porous starch dispersion in water of poor shortcomings, and the higher development value. |
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