Lexicon development and quantitative descriptive analysis of Hunan fuzhuan brick tea infusion. Li Huan-Huan,Luo Li-Yong,Wang Jie,Fu Dong-He,Zeng Liang Food research international (Ottawa, Ont.) Twenty-seven representative Hunan fuzhuan brick teas were collected to develop a terminology lexicon and a quantitative descriptive analysis (QDA) method suitable for the sensory evaluation of Hunan fuzhuan brick tea infusion. Ten trained panelists developed a terminology lexicon comprised of eleven aroma and six taste attributes and evaluated the intensities of sensory attributes of each sample by conducting the QDA method. The QDA results showed that seventeen attributes listed in the final lexicon can be used to evaluate the quality of Hunan fuzhuan brick tea infusion properly, among which five aroma attributes, overall aroma, smoky, floral, fermented, and sweet (fruit), and one taste attribute, bitter, were the characteristic attributes to distinguish the differences in the sample qualities. Another panel made up of four professional cuppers evaluated samples by the cupping method to analyze the applicability and accuracy of the lexicon and the QDA method. The results showed that both the cupping method and QDA can be effectively used to evaluate Hunan fuzhuan brick tea quality, and their evaluation results showed high consistency and mutual complementation. This information will be beneficial for developing a sensory evaluation method and quality control for Hunan fuzhuan brick tea. 10.1016/j.foodres.2019.02.047

Shifts in diversity and function of the bacterial community during the manufacture of Fu brick tea. Li Qin,Li Yongdi,Luo Yu,Zhang Yiyang,Chen Yuan,Lin Haiyan,Wang Kunbo,Huang Jianan,Liu Zhonghua Food microbiology To better understand the effects of bacteria on the characteristics of Fu brick tea, we investigated bacterial community structure as well as the predicted functions of identified bacteria and their correlations with chemical compounds during the manufacturing process. Overall, Klebsiella species dominated during the initial stage of processing, but were quickly replaced by Pseudomonas, Lactococcus, Stenotrophomonas, Enterococcus, and Bacillus species, which remained stable until the end of the manufacturing process. Network analysis identified 11 bacterial genera as keystone taxa, which contributed to the stabilization of the microbial community in the co-occurrence network. Bacterial taxa were grouped into eight modules, with the dominant genera mainly distributed amongst modules I and Ⅵ, which were involved in metabolism of carbon and flavor compounds in the Fu brick tea ecosystem. Using bidirectional orthogonal partial least squares analysis, 19 bacterial genera were identified as core functional genera linked to the metabolism of chemical compounds during the manufacturing process, while three genera, namely Klebsiella, Lactococcus, and Bacillus, also dominated the Fu brick tea fermentation process. These findings provide new insights into Fu Brick tea bacterial community variation and increased our understanding of the core functional bacterial genera involved in the manufacture of Fu brick tea. 10.1016/j.fm.2019.01.001

Microbial bioconversion of the chemical components in dark tea. Zhu Ming-Zhi,Li Na,Zhou Fang,Ouyang Jian,Lu Dan-Min,Xu Wei,Li Juan,Lin Hai-Yan,Zhang Zhang,Xiao Jian-Bo,Wang Kun-Bo,Huang Jian-An,Liu Zhong-Hua,Wu Jian-Lin Food chemistry Dark tea is a unique fermented tea produced by solid-state fermentation of tea leaves (Camellia sinensis). It includes ripe Pu-erh tea, Fu brick tea, Liupao tea, and other teas. Microbial fermentation is considered to be the key factor controlling the quality of dark tea. It involves a series of reactions that modify the chemical constituents of tea leaves. These chemical conversions during microbial fermentation of dark tea are associated with a variety of functional core microorganisms. Further, Multi-omics approaches have been used to reveal the microbial impact on the conversion of the chemical components in dark tea. In the present review, we provide an overview of the most recent advances in the knowledge of the microbial bioconversion of the chemical components in dark tea, including the chemical composition of dark tea, microbial community composition and dynamics during the fermentation process, and the role of microorganisms in biotransformation of chemical constituents. 10.1016/j.foodchem.2019.126043