Dynamic Changes in Biochemical Components during Fermentation of Sweet Fermented Oat

WU Han;XIAO Yu;LI Wei;RUI Xin;WANG Dan;XU Xiao;MA Yuxiao;HUANG Lu;DONG Mingsheng;College of Food Science and Technology,Nanjing Agricultural University;

sweet fermented oat;;traditional culture starter;;biochemical components;;ergosterol;;oat protein

Tianpei(sweet fermented oat) is a famous local snack in Lanzhou which is traditionally made by fermentation of highland barley and oat for 2 or 3 days.In this paper,during fermentation,physicochemical changes were investigated,and the production of ergosterol and proteolysis were monitored by high performance liquid chromatography(HPLC) and sodium dodecyl sulfate polyacrylamide-gel electrophoresis(SDS-PAGE),respectively.Results showed that p H value decreased rapidly and reached the lowest level of 3.90,and total acidity showed a gradual increase to the highest level of 0.74% as the fermentation progressed.The content of ammonium nitrogen increased to the highest value of 0.06% during 24–36 h and then dropped rapidly.Reducing sugar content increased significantly to the highest value of 41.17 g/100 g during the first 36 h and then decreased until the end of fermentation.Continually,the content of ergosterol augmented and reached its final value of 213.64 μg/g.High-molecular-weight oat proteins were significantly hydrolyzed during fermentation,especially for the protein with a molecular weight of 35.08 k D,which had a mean degradation rate of 55.57%.