Fermentation Conditions Optimization Of Fermented Rice Noodles And Analysis Of Aroma Component

In this paper, we use indica rice as raw materials,pulping with some indica rice and late indica rice,forming the fermented rice noodles by fermenting streaming crowding silk,then hydrolysis with pullulanase and papain.pullulanase is a kind of specific debranching amylase.It can hydrolysis ?-1,6- glycosidic bonds of amylopectin,Improving the properties of rice gel by increasing the content of amylose in rice.Papain can hydrolysis rice protein into free amino acids,It not only improves the nutritional value of rice but also providing energy source of strain fermentation.Saccharomyces cerevisiae and Lactobacillus plantarum iare a two dominant species in natural fermentation It can improve the quality of rice noodlesand add aroma smell by putting them into rice milk.In this paper,we investigated the process of enzymatic hydrolysis and strain fermentation,the main contents are as follows:1?Hydrolysising rice starch with pullulanase to increase rice amylose content Determined amylose content with a national standard spectrophotometric method and single factor and orthogonal experiment.Obtained the optimum process parameters of hydrolyzed rice starch:in the hydrolysis p H 4.5, enzyme dosage 65 PUN/g,hydrolysis time 3h,reaction temperature at 50?,we can get the best hydrolysis effect,rice starch content of amylose reached 27.12% after hydrolysised2?Hydrolysising rice starch with papain to increase rice free amino acids content Determined free amino acids content with a national standard spectrophotometric method and single factor and orthogonal experiment.Obtained the optimum process parameters of hydrolyzed rice protein:in the hydrolysis p H5, enzyme dosage10000u/g,hydrolysis time 4h,reaction temperature at 65 ?,we can get the best hydrolysis effect,rice free amino acids content reached 24.05% after hydrolysised3 ? We filter the strain from nature fermentation,get dominant strains of Saccharomyces cerevisiae and Lactobacillus plantarum,explore the growth conditions of two kinds of strain,get optimal culture conditions of Saccharomycescerevisiae:optimal culture temperature35?,optimal culture time 12 h,optimal culture conditions of Lactobacillus plantarum:optimal culture temperature30 ?,optimal culture time 15 h.4?Product fermented rice noodles with the two kinds of strain,use elasticities of fermented rice noodles as reference index,by single factor and orthogonal experiment.Obtained the optimum process parameters of fermented rice noodles:strain ratio 1:1,plasma volume10%,fermented temperature 30 ?,fermented time 16 h.In this combination of conditions,the elasticities of fermented rice noodles would reach 0.896.5?Compare aroma components between fermented rice noodles and unfermented rice noodles, analysis their aroma components by SPME-GC-MS,then,there are 18 kinds aroma components in fermented rice noodles and 10 kinds aroma components in unfermented rice noodles,most of them are esters, alkanes and alcohols.Besides,we produced sensory evaluation table of fermented rice noodles to evaluation of the quality of fermented rice noodles.