Optimization on drum drying processing technology of sweet corn powder

According to the problems of imbibition and poor sensory state of the sweet corn flour by the drum drying from enzymolysis sweet corn, the processing technology of modified sweet corn powder made by sweet corn pulp was studied. Based on water injectivity index and sensory evaluation, the waxy maize starch was used as cross-linking agent with optimal dosage of 25%. According to gelatinization degree and effect of drum drying, the optimum gelatinization temperature was 85℃ and the gelatinization time was 30 min. On the basis of the results of single factor experiment, response surface experiment of three factors and three levels was designed. Concentration of modified sweet corn pulp, steam pressure, rotate speed of the drum were investigated, and taking water absorption index and sensory evaluation as indexes, a regression equation was derived from the data obtained and the results were analyzed by statistic methods. The optimum drum drying conditions were as following: concentration of modified sweet corn syrup was 17%; steam pressure was 0.5 MPa; rotate speed of the drum was 2.5 r/min. Under these conditions, sensory score of drum drying product was 8.75, water absorption index was 5.3. Verification tests showed that all values were within 95% confidence limits. The results are in conformity with the anticipation, which can provide a guidance for industrialized production of sweet corn flour for infants.