Study On The Technology And Shelf-life Of Beverage Prepared By Corn Germination

Corn is one of the most important food crops in China,which is known as "gold crop".Horsetooth corn is the main variety of High-yield Cultivation in China,while waxy corn is called "Chinese waxy variety".Although corn is rich in nutrition,it is called "coarse grain" and its product development is limited.In this experiment,using horse tooth corn and waxy corn as raw materials,the content changes of soluble protein,reducing sugar,dry matter and ?-aminobutyric acid(GABA)in the two kinds of corn at different germination times were studied by the method of preparing corn beverage after germination,so as to determine the best germination time,and to measure other conventional nutrients and antioxidant capacity at corresponding time.Taking the germinated corn as the raw material,the enzyme hydrolysis technology was used to improve the stability and soluble solid content of the beverage,and the optimal parameters of the enzyme hydrolysis technology were determined by single factor and orthogonal test.On this basis,the optimal formula technology of the corn beverage was studied.The shelf life of two kinds of corn drinks was evaluated by analyzing the changes of sensory quality,soluble solid content,GABA content,microbial index and total antioxidant capacity under the storage condition of 4?.The main results are as follows:After germination,the content of soluble protein decreased first and then increased,the content of reducing sugar and GABA,the total antioxidant capacity and DPPH free radical scavenging capacity increased significantly(P<0.05),while the content of dry matter did not decrease significantly.The contents of starch,reducing sugar,soluble protein and GABA in waxy corn were significantly higher than those in horsetooth corn(P<0.05).According to the content changes of the corresponding judging indexes,the best germination time of corn for beverage production was selected as the fourth day for horsetooth corn and the third day for waxy corn.The results of the enzymatic hydrolysis process of germinated corn indicate that the optimal enzymatic hydrolysis parameters of horsetooth corn:the addition amount of ?-amylase was 0.1%,the enzymatic hydrolysis temperature was 60?,and the enzymatic hydrolysis time was 35min.The optimal enzymatic hydrolysis parameters of waxy corn:the addition amount of ?-amylase was 0.15%,the enzymolysis temperature was 50?,and the enzymolysis time was 45min.Under the conditions,the two kinds of corn drinks have the highest stability,the lowest degree of browning,and high soluble solids content.The amount of enzyme added has the greatest influence on the enzymatic hydrolysis process.The orthogonal test results of corn beverage formula show that the best formula of horsetooth corn drink was determined as:xylitol content 3.6%,citric acid content 0.028%,salt content 0.015%,which made the horsetooth corn beverage had moderate sweet and sour taste and strong corn flavor.The optimal formula of waxy corn drink was determined as:xylitol content 2.4%,citric acid content 0.022%,edible salt content 0.01%and corn flavor content 0.09%.Under these condition,waxy corn beverage had the advantages of good taste,proper proportion of acid and sweet,and rich corn flavor.The shelf life test of corn beverage showed that the longest shelf life of horsetooth corn beverage was 8 days,and the longest shelf life of waxy corn beverage was 6 days.