Biotransformation of green tea (Camellia sinensis) by wine yeast Saccharomyces cerevisiae

Abstract

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.

Impact of tea leaves categories on physicochemical, antioxidant, and sensorial profiles of tea wine

“…The reason for the decline of antioxidant activities may be that some antioxidant substances, such as tea polyphenols, were degraded in tea wine fermentation. Similar results were reported in previous research ( 31 , 32 ).…”

Assessment of Tannin Tolerant Non-Saccharomyces Yeasts Isolated from Miang for Production of Health-Targeted Beverage Using Miang Processing Byproducts

“…Dzialo et al [ 62 ] suggested isoamyl alcohol and 2-phenylethanol were the major fuel alcohols found in alcoholic beverages. In this study, MF-broth fermentation revealed the presence of isoamyl alcohol and 2-phenylethanol, with alcohol produced at a higher level in both the SF and CF with S. cerevisiae TISTR 5088 and W. anomalus P2, which was consistent with previous studies [ 34 , 36 , 43 , 65 ]. However, although in the original MF-broth, a high quantity of (Z)-3-hexen-1-ol and benzyl alcohol (known as tea leaf alcohol) was found, after fermentation that compound was reduced by the yeast [ 66 ].…”

“…From these studies, non- Saccharomyces yeasts were recognized for their low ethanol fermentation rate, in comparison to S. cerevisiae . W. anomalus has previously been investigated in the production of low alcohol with high levels of esters, such as in kiwi wine [ 34 ], muscat bailey wine [ 13 ], apple wine [ 35 ] and Baijiu [ 36 ]. The members of the genus Cyberlindnera , as well as C. subsufficiens , C. mrakii , C. jadinii , C. fabianii and C. saturnus [ 9 , 37 , 38 , 39 ] were studied on the generation of a fruity aroma in non-alcoholic beer, but C. rhodanensis has not been reported for use in fermented beverages.…”

“…EC, EGC and EGCG were stable, except for the samples inoculated with C. rhodanensis P3, in the single and co-cultured fermentations, and showed a higher content of EC and EGC, compared to the original MF-broth ( Table 3 ). The increase in EC and EGC might be due to the hydrolysis of gallate polyphenols (EGCG) by esterase or tannase from the yeast [ 36 ]. However, the reduction of the total catechins in all fermented samples might be from the biotransformation by the yeast.…”

UPLC-Q-TOF-MS based metabolomics and chemometric analyses for green tea fermented with Saccharomyces boulardii CNCM I-745 and Lactiplantibacillus plantarum 299V

“…From the UPLC-Q-TOF-MS analysis, the glycoside of 2-phenylethanol (2-phenylethyl-6-O-β-D-xylopyranosyl- β-D-glucopyranoside) was also found ( Fig. 3 ), which further verified the results discussed in our previous study that the key flavor compound 2-phenylethanol was not only from phenylalanine metabolism but also from glycoside precursor hydrolysis ( Wang et al, 2020 ).

Fig.

…”