Summary: | 碩士 === 國立嘉義大學 === 食品科學系研究所 === 99 === Increase consumption of dietary fiber exerts beneficial effects for metabolite. In addition, dietary fiber-rich materials are suitable as a prebiotic for probiotic growth. Cereals and edible mushroom are important source of dietary fibers. However, commercial probioitic products with cereals and edible mushrooms in fermented product are not common. In this study, two cereals (oats andcoix seeds) and two mushrooms (tremellas and golden mushroom) weredried,pulverized, mixed with skim milk powder, and fermented with various ratios of mixed culture of Lactobacillus bulgaricus and Lactobacillus plantarum. The quality characteristics of the fermentation productswere investigated.
Our results showed material sources affected the growth of Lactobacillus. Higher Lactobacillus growth and the titratable acidity concentration are observed in mushroom based media than cereal based media. The ratios of the mixed culture of Lactobacillus did not affect the characteristics of products. LowerLactobacillus growth in coix seeds of cereal group and unpleasant flavor of the product in golden mushrooms of edible mushroom group, therefore no further experiment was performed using the two materials.
Color of fermentation product was affected by raw material but not byby different ratios of the mixed cultures. Overall acceptability in sensory evaluation followed the order: dairy, oat and tremella-based media. The low acceptability of tremella is mainly due to the high consistency and granular texture of the product. According to Pearson’s correlation coefficient analysis, the content of dietary fiber is highly negatively correlated with the overall acceptability(>0.9). However, tremellapossessing the highest dietary fiber content exerted the strongest capability to delay the dialysis of reducing sugars in vitro test.
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