Food Science and Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, Science Drive 3, Singapore, 117543.
Mane SEA Pte Ltd, Biopolis Drive 3, Singapore, 138623.
J Food Sci. 2020 Feb;85(2):306-315. doi: 10.1111/1750-3841.15026. Epub 2020 Jan 24.
Wine yeast Saccharomyces cerevisiae 71B was used in fermentation of green tea to modulate the volatiles and nonvolatiles. After fermentation, higher alcohols, esters, and acids, such as isoamyl alcohol, isobutanol, ethyl octanoate, ethyl decanoate, octanoic, and decanoic acids were generated. Some key aroma compounds of tea including linalool, hotrienol, dihydroactinidiolide, and 2-phenylethanol increased significantly. Among these compounds, linalool and 2-phenylethanol increased by 1.3- and 10-fold, respectively, which impart floral and fruity notes to fermented green tea. Alkaloids including caffeine, theobromine, and theophylline were reduced significantly after fermentation, while the most important free amino acid in tea, theanine, was not metabolized by S. cerevisiae. Tea catechins decreased whereas gallic and caffeic acids increased significantly, resulting in the unchanged antioxidant capacity of the fermented green tea. Hence, this work highlighted the potential of using S. cerevisiae to modulate green tea aroma and nonvolatiles. PRACTICAL APPLICATION: A novel fermented tea is produced by yeast fermentation. Saccharomyces cerevisiae led to significant changes in tea volatiles and nonvolatiles. Antioxidant capacity remained stable after fermentation.
利用葡萄酒酵母酿酒酵母 71B 对绿茶进行发酵，以调节其挥发性和非挥发性成分。发酵后，生成了较高的醇、酯和酸，如异戊醇、异丁醇、辛酸乙酯、癸酸乙酯、辛酸和癸酸。一些关键的茶香气化合物，如芳樟醇、香叶醇、二氢猕猴桃内酯和苯乙醇显著增加。在这些化合物中，芳樟醇和苯乙醇分别增加了 1.3 倍和 10 倍，赋予了发酵绿茶花香和果香。发酵后，生物碱如咖啡因、可可碱和茶碱显著减少，而茶中最重要的游离氨基酸——茶氨酸，没有被酿酒酵母代谢。儿茶素减少，而没食子酸和咖啡酸显著增加，导致发酵绿茶的抗氧化能力保持不变。因此，这项工作强调了利用酿酒酵母来调节绿茶香气和非挥发性成分的潜力。
通过酵母发酵生产出一种新型发酵茶。酿酒酵母导致茶的挥发性和非挥发性成分发生显著变化。发酵后抗氧化能力保持稳定。
