Research On Improve Pigment Content And Stability Of Purple Corn Wholegrain Beverage

With the improvement of people's living standards,people's requirements of the nutritional of the diet continue to increase,so that the wholegrain food become popular.The wholegrain beverage is a new type of beverage which is processed by almost all the ingredients such as endosperm,germ and cortex in the grain.It is rich in dietary fiber and various antioxidant substances.It also has the effect of enhancing satiety,anti-aging and preventing common cerebrovascular disease and so on.Compared with ordinary corn,the purple corn has a higher nutritional value,and the trace element content is 2 to 8 times than other grains.The purple corn is rich in melanin,which has the ability to remove free radicals in the human body and reduce the accumulation of lipid.At present,China's purple corn used in fresh food usually,less processed products.Commercially purple corn beverage has generally low dissolution rate of melanin,poor product stability and other issues,which lead the loss of purple maize nutrient and a great waste of resources.In this study,fresh maize was used as raw material to study the extraction and stability of zeolite pigment at first.Secondly,the dissolution rate of pigment in maize grain was improved by alkali treatment were studied.Finally,the optimum formula of corn starch concentrate was optimized,and antioxidant activity of raw material and purple corn whole cereal beverage were studied.The main findings are as follows:1.The ratio of material to liquid was 1:20,the treatment temperature is 60 ?,the treatment time were 2 h,pH 3.0,at this time,the purple corn cob pigment extraction rate was 32.73%.2.The effect of the light,temperature,pH,metal ion and the food raw materials on the stability of the pigment of purple corn cod were also studied.The results show that the light of the purple corn cob pigment is poor,the thermal stability of the purple corn pigment is poor and the degeration under different pH conditions show different colors.With,the increase of pH value,the results are followed by:rad,purple,black,green,yellow.At the same time,the preservation rate of pigment is affected by pH value,and the stability is better under acid condition.The effect of K+,Na+,Ga2+ and Mg2+ on the stability of the pigment was not significant;However,the Cu2+ and Fe3+ reduce the stability of the purple corn cod pigment significantly;Sucrose and soluble starch all decrease the absorbance of the pigment,and the citric acid increase the absorbance value.3.Improving the dissolution rate of pigment in purple corn grains by Alkaline Treatment.The optimum conditions of pretreatment of purple corn are as follows:NaOH concentration 1.5%,heating temperature 80 ?,heating time 2 min.the absorbance value of the pigment under this condition was 0.77 ± 0.00,the sensory score of the treated maize grain As follows:80.3 ±2.7.4.The single factor test and orthogonal test were used to determine the formula for the· complex stabilizer in the purple corn whole grain beverage.purple whole grains of corn beverage compound stabilizer formula for:CMCC-Na concentration 1.4 ‰,sodium alginate concentration 1.3‰,concentration of sucrose ester 0.6‰,MCC concentration 1.8‰.Under this condition,the precipitation rate was 33.07 ±0.13%.5.The absorbances of purple corn wholegrains were 0.17 and 0.43,respectively,which were prepared by alkali treatment and treated purple maize grain.The absorbance of DPPH free radicals was 93.13%and 80.57%.The absorbance of DPPH radical was 89.84%.The absorbance of the beverage was 0.59,and the absorbance of the beverage was 37.21%higher than that of the pigment.The DPPH radical scavenging rate was 16.37%.1%of the purple corn cob pigment solution absorbance of 1.57,DPPH free radical scavenging rate of 89.84%.The absorbance of the beverage which add the cob pigment was 0.59,and the absorbance of the beverage was 37.21%higher than that of the non-added pigment,and the DPPH radical scavenging rate was 16.37%.6.The purple corn whole grain beverage appearance was light purple,color uniformity,taste smooth,no obvious stratification or precipitation phenomenon,and has a strong purple corn aroma.