Study On The Processing Technology And Formula Of Brewing Rice Powder For Middle Aged And Old Aged People

With the increasing degree of global population aging, the diet health problems of the middle aged and old aged people(MOP) are paying more and more attention. In this dissertation, the key processing technology and formula of brewing rice powder for MOP was studied in order to develop a new kind of specific rice powder suitable to the physiological characteristics and nutritional needs for MOP. Through these researches, the main results are as follows:Study on enzymatic hydrolysis process of base material of rice powder. The composite enzyme mixture, slurry concentration, enzymatic hydrolysis time, enzymatic hydrolysis temperature, enzyme concentration were chosen as the single factors to study the effect on the degree of hydrolysis (DE value). Based on the single factor experiments, the composite enzyme mixture was 1:3, and using Box-Behnken design and response surface analysis, the process parameters of enzyme solution were optimized, and the base material of rice powder was prepared by spray drying. The enzymatic hydrolysis process optimization results showed that:slurry concentration 13%, enzymatic hydrolysis time 42 min, enzymatic hydrolysis temperature 69℃ and enzyme concentration 0.34%(a-amylase and (3-amylase concentration 7U/g、225U/g). Under these conditions, the hydrolysis degree of base material was 33.02%, without residual enzyme activity, the starch digestion index was 50.62%, higher 21.71% than non-enzymatic process one. The foundation for the rice powder development has been laid.Optimization of spray drying process parameters of rice powder base material. The effect of four factors on the powder yield and moisture content was studied:inlet air temperature, inlet material flow, inlet material concentration and P-CD addition, using the single factor and orthogonal tests, the factors impact on index size was inlet air temperature> P-CD addition> inlet material flow> inlet material concentration, and the optimization results of spray drying process conditions for rice powder base material were as follows:inlet air temperature 180℃, inlet material flow 54 mL/h, inlet material concentration 20%, β-CD addition 10%. Under these conditions, the flour yield of rice flour base material was 57%, and the moisture content was 3.42%.According to the characteristics of dietary nutrition for MOP, three kinds of different flavor and functional rice powder formulations were designed by linear programming method. Formulation Ⅰ:rice powder 58.5%, Chinese wolfberry powder 6.1%. jujube powder 7.4%, full-milk powder 6%, soy protein powder 9.5%. xylitol 10%; Formulation Ⅱ:rice powder 57.6%, dandelion powder 7.3%, green tea powder 6.2%, soy protein powder 8.5%, full-milk powder 5.4%, oil powder 5.9%, xylitol 9.0%; Formulation Ⅲ:rice powder 55%, black sesame seeds 21.3%, fungus powder 11.3%,soy protein powder 4.1%, oil powder 8.3%.Based on the determination of the rice powder formulations, according to the calculation results, the constraint conditions and the recommended intake content of MOP, the nutrition of three kinds of rice powder were fortified. Formulation Ⅰ:the addition of VA, VB, VC, VE, calcium carbonate, ferrous sulfate and zinc sulfate for per 100 g powder were respectively 271 μg,0.6 mg,50 mg,7 mg,1052 mg,11 mg,150 mg; formulation Ⅱ:the addition of VA, VB, VC, VE, calcium carbonate for per 100 g powder were respectively 313μg,0.6 mg,50 mg,7 mg, 1035 mg; formulation Ⅲ:the addition of VA, VB, VC, calcium carbonate for per 100 g powder were respectively 399 μg,0.5 mg,50 mg,740 mg.The main nutrition content and physical and chemical indexes and sensory testing of three kinds of rice powder products were detected. The results were as follows:The nutrient content of the three kinds of rice powder was in line with the standard of the recommended intake of dietary nutrition for MOP, and the rice powder color was uniform, no impurities, agglomeration, etc. After brewing, the product had delicate taste, moderate sweetness, with the better aroma, no peculiar smell. The dispersion, solubility, stability and recovery of rice flour were good. The formulation Ⅰ and the formulation Ⅲ had good mobility, the liquidity of formula Ⅱ was moderate. Sensory evaluation of the three formulations were more than 80 points, the quality was good.