Study On Extruding Preparation Of Cereals Powder And Its Storage Stabilization

Our study aimed to design two puffed cereals powder, the beneficial cerealspowder for old people and the natural high-calcium cereals powder for theteenagers.In consideration of nutritional complementarity and preparation technology, thebrown rice powder, wheat flour, oat flour, millet powder, waxy corn powder, soypowder, wheat bran powder were chosen as material for the production of puffedcereals powder. Based on the nutrition analysis, the puffed cereals powderformulation was computed with the linear programming by the Excel program. Theformula of the beneficial cereals powder was: brown rice powder18.00%, wheatflour5.00%, oat flour7.00%, millet powder5.00%, corn powder51.88%, soypowder5.12%, wheat bran powder8.00%. The mixed material cost was￥3.51/kg.The formula of the natural high-calcium cereals powder was: brown rice powder25.00%, wheat flour11.41%, oat flour14.62%, millet powder8.00%, corn powder20.97%, soy powder20.00%. The mixed material cost was￥4.22/kg.Consideration of the minerals and vitamins concentration in the materials and thewastage during extrusion, the addition concentration of fortifier to the puffedcereals powder was determined.27.0mg ferrous gluconate,7.5mg Zinc gluconate,0.3mg vitamin B₁,0.3mg vitamin B₂,0.3mg vitamin B₆were added to100gbeneficial cereals powder;15.0mg ferrous gluconate,8.0mg Zinc gluconate,0.3mgvitamin B₁,0.3mg vitamin B₂,0.4mg vitamin B₆were added to100g naturalhigh-calcium cereals powder.By the single factor test, proper extrusion parameters are obtained: materialmoisture14～20%, screw speed110～170r/min, barrel temperature145～175℃,feed speed15～30r/min. On the orthogonal experiment, the factor that affecting theproduct quality was determined by range analysis and variance analysis, they arematerial moisture, barrel temperature, screw speed and feed speed. The bestextrusion parameters were: material moisture16%, screw speed150r/min, thethree sections of barrel temperature80-145-165℃, and feed speed20r/min. Theoptimum quality indicators of products were obtained as follows: the radialexpansion of the beneficial cereals powder was3.068, the gelatinization degree was 97.92%, the index of water absorption was436.28%, the index of water solubilitywas26.35%, the product moisture was7.15%, and the sensory composite score was7.86; the radial expansion of the natural high-calcium cereals powder was2.606,the gelatinization degree was94.39%, the index of water absorption was379.66%,the index of water solubility was21.29%, the product moisture was7.02%, and thesensory composite score was7.93.The puffed cereals powder had high nutriment reference values of iron and zinc,and they were rich of dietary fiber. The concentration of the dietary fiber in thebeneficial cereals powder reached the equivalent level in national high dietary fiberfood. The natural high-calcium cereals powder had more protein than the generalpuffed food grains. Compared with the cereals quick drink, the puffed cerealspowder we designed had advantages as follow:①It was specially fortified withiron, zinc and vitamin Bs;②No emulsifier and no sweetener;③Smaller averageparticle size and larger specific surface area;④The particle surface roughness, arelinked closely with one another;⑤Better water absorption.The storage time had a great influence on the water content and the acid value,and little effect on the index of water absorption of the product.