Penicillium simplicissimum possessing high potential to develop decaffeinated Qingzhuan tea

The excessive intake of caffeine might adversely affect health, so decaffeinated food becomes a hot topic for investigation. Penicillium simplicissimum 4-17 was inoculated into sun-dried green tea for the pile fermentation (QZTWP) at a pilot scale to develop decaffeinated Qingzhuan tea (QZT). Through comparisons in chemical compositions, fungal community structure and sensory qualities, the results showed that after 21-d pile fermentation, most quality components in QZTWP were same or similar to those in naturally fermented QZT, except caffeine. Caffeine decreased nearly 50%, and some quality components were better in QZTWP than those in naturally fermented QZT. The addition of P. simplicissimum 4-17 couldn't change the dominant strains in the pile fermentation of QZT, but was conducive to increasing the amount of Saccharomyces, Candida, and Penicillium and to inhibiting the unfavorable strains. The results confirmed that P. simplicissimum 4-17 not only contributed high caffeine degradation ability of pilot fermentation of QZT, but also helped to improve the comprehensive quality of QZT. It means that there is a great potential of P. simplicissimum 4-17 for industrial production of decaffeinated QZT.

Automated summary

This study investigated the production of decaffeinated Qingzhuan tea (QZT) by inoculating Penicillium simplicissimum 4-17 into sun-dried green tea for pile fermentation. The results showed that after 21-day fermentation, most quality components in the decaffeinated tea were similar to those in naturally fermented QZT, except for caffeine. The addition of P. simplicissimum 4-17 contributed to high caffeine degradation ability and improved the overall quality of QZT.