Preparation And Properites Of High-protein Instant Reconstitable Corn Powder

With the rapid economic development and the continuous improvement of people’sliving standards, food nutrition and dietary pattern was starting to be paid attention by moreand more consumers. Therefore, the study on economic instant nutritious food of high proteinis a trend of food market. In this paper, corn flour as the main raw material with the additionof low-temperature defatted peanut flour was used to develop an easily digested, convenientready-to-eat reconstituted food in high-protein and high added value by extrusion technology,developed. The main conclusions of this research were as follows:1. The obtained optimum extrusion conditions of corn were particle size of60mesh,24.5%feed moisture content, extrusion temperature of164℃, and screw speed400r/min. Theexpansion ratio with optimized conditions of corn was3.42. The mathematic model couldexactly forecast the expansion ratio of corn.2. Due to the addition of low-temperature defatted peanut protein flour, the maturationdegree，bulk density, degree of gelatinization and WSI of corn extrusion increased，thegelatinization parameters (except for basic unchanged outside of peak time), expansion ratioand WAI of corn extrusion decreased. Bulk density increased. The color gradually deepenedwith increasing low-temperature defatted peanut protein flour. The degree of gelatinization ofthe products reached the maximum (94.74%), when30%defatted peanut protein flour wasadded. At the addition level of40%, the extrusion products had better WAI and WSI.Extrusion products had better sensory quality between20%and40%defatted peanut proteinflour.Under this experimental conditions, the amount of defatted peanut protein flour shouldnot exceed40%, considering the various indicators, and ultimately determined that40%defatted peanut protein powder was added.3. With the increase of the refining extent of the reconstituted powder，the angle ofrepose and slip was gradually increased, the liquidity was weaken.The rehydration wasgradually smaller, the dispersibility was higher. Combining with the reconstituted stability,the best granularity of reconstituted powder for recombination was80mesh.4. Based on the single-factor test, using the orthogonal test and fuzzy comprehensiveevaluation method, the results indicated that the best combination of flavoring agent was maltdextrin5%, sugar2.5%, salt0.1%.5. After testing, protein content of the high-protein corn reconstituted powder had reach-ed23.18%, which was about3.35times than that of commercial instant corn powder. Compa-red to instant corn powder, moisture and crude fat were lower to store easily and it had higher degree of gelatinization. High-protein corn reconstituted powder was rich in corn flav-orand peanut flavor, brewing, and palatability of smooth, non-caking, has a high degree ofgelatinization. It was easily prepared, smooth and palatable and non-caking. Therefore it canserve as a high protein food for instant ready to drink.