| The extraction and physicochemical properties of the starch and protein from oats were studied in this dissertation, using Oats flour as raw material.The oats starch and protein was Separated by using alkali, all of the factors were discussed, the best technical parameters of the separation was gained though the mathematical analysis by means of response surface on the basis of the single-factor test, the oats starch was Purified with the neutral enzyme, the different conditions which would effect of purification of starch was researched; Aether was used to purify the oat protein, the number of treatment which would effect the purification of the oats protein was studied ;The physicochemical properties of oats starch and the protein were studied under the optimum process, the Main conclusions are as follows:The optimal extraction condition were: pH10.4,ratio of material to solvent 1:6.7, temperature 25℃, time 2.9h; in this condition the yield of oats starch was 63.38%,with 1.19% protein remained;the yield of oats protein was 10.2%,purity was 70.5%.The optimal condition of the purification of the oats starch were temperature 25℃, pH7, ratio of material to solvent 1:6, E/s 48AU/kg,time 60min,the protein remained in the starch was decreased to 0.6%,the yield of the starch was 60.26%.The purification of the oats protein was to decrease the lipid in the protein, after 3times of the treatment of the aether, the content of the fat decreased from 24.7% to 3.5%, the purity of the protein reached 94.73%.Scanning electron microscope (SEM) was used the to observe the structure characteristic, the particle size of the oats starch, DSC to study its pasting temperature, The AR1000 dynamic rheometer to analyzes its gelatin speed, the gelatin intensity and the thermal stability, It was found that average diameter of the oats starch particle is 1～5um,distributing non-uniform,assuming the elliptic type and the edges and corners. Swollens strength of the oats starch at 30℃is 1.35, solubility 1.2%, when swollens strength and the solubility increases separately to 4.43 and 4.56% at 70℃;its onset temperature of turning paste is 53.60℃,peak temperature 62.00℃,cease temperature 69.00℃,heat enthalpy 6.115 J/g;Gelatin speed 375pa/min, the gelatin intensity 7500pa, and the thermal stability 1500pa . after being set for 24 hours still ,the volume of the starch paste remain 42.5ml, Through the logarithm regression analysis, regression equation of curve of ratio of the volume of liquid above to the whole system is y = 17.66Ln(x) + 4.5904,regression coefficient R~2 =0.9974. the temperature of oats starch slurry system in the boiled water assumes the logarithm relations along with the time goes, The regression equation is y = 20.815Ln(x) + 12.688, R~2=0.9813.The physicochemical property of the oats protein was researched with the machine of SEM and AR1000 dynamic rheometer analyzes and so on,the result shows that: The protein is wrapping the oats starch,its maximum molecular weight 66.2k, the smallest molecular weight is between14.4k～20.0k;When at pH5, its ability of foaming is the worst, the foaming stability is the best, the emulsification is worst, the emulsification stability is best; during the first temperature ascending step, G' reduces first then increases with the temperature raising,the smallest is 48.1pa at 62.1℃, the highest is 369.0pa at 90.8℃; G"has the same change tendency with G'; the tg(delta)>1 between 20℃～28℃, the stickiness is bigger than the elasticity; tg(delta)<1between 28℃～100℃, the stickiness is smaller than the elasticity. Gelatin speed 375pa/min, the gelatin intensity 9194.0pa, and the thermal stability 844.1 pa.
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