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To explore the effect of room temperature storage on the flavor quality and biochemical composition of flower and fruit scented black tea, this study compared the sensory flavor quality of flower and fruit scented black tea produced in the years 2019, 2020, 2021 and 2022 and stored at room temperature, and it detected volatile and non-volatile compounds in the tea by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and ultra-performance liquid chromatography coupled to orbitrap high resolution mass spectrometry (UPLC-Orbitrap-MS). The results showed that the sensory quality of flower and fruit scented black tea was significantly affected by storage at room temperature, and the tea lost its floral and fruity aroma characteristics after three years of storage at room temperature; its quality characteristic was mature sour taste. The tea samples were divided into four groups of age by principal component analysis (PCA) and hierarchical cluster analysis (HCA). Totally 15 volatile differential compounds such as linalool, cis-β-ocimene, and hexanoic acid (VIP > 1 and P 2 and P < 0.05) were selected by partial least squares discriminant analysis (PLS-DA) and one-way analysis of variance (ANOVA). The content of volatile compounds such as linalool, hexanal, cis-β-ocimene, and 2-pentylfuran decreased with increasing storage time, while the contents of hexanoic acid, dihydroactinidolide 1-ethyl-2-formyl-1H-pyrrole, and β-ionone increased. The contents of non-volatile compounds such as most amino acids, nucleotides, sugars, tea polyphenols tended to decrease with increasing storage time, while the contents of organic acids and lipids showed an increasing trend. The results obtained from this study can provide a scientific basis for elucidating the quality changes of flower and fruit scented black tea during storage and help guide its rational storage and scientific consumption.

This study investigated the changes in the aroma of jasmine tea during storage. Solid-phase micro-extraction (SPME)–gas chromatography (GC)-mass spectrometry (MS) and stir bar sorptive extraction (SBSE)-GC-MS were combined to detect all volatile compounds. GC-olfactometry (GC-O), odor activity value (OAV), and p-value were employed to analyze and identify the key aroma compounds in six jasmine tea samples stored for different durations. Nine key aroma compounds were discovered, namely (Z)-3-hexen-1-yl acetate, methyl anthranilate, methyl salicylate, trans-β-ionone, linalool, geraniol, (Z)-4-heptenal, benzoic acid methyl ester, and benzoic acid ethyl ester. The importance of these compounds was confirmed through the aroma addition experiment. Correlation analysis showed that (Z)-4-heptenal might be the main reason for the increase in the stale aroma of jasmine tea. Through sensory evaluation and specific experimental analysis, it can be concluded that jasmine tea had the best aroma after 3 years of storage, and too long a storage time may cause the overall aroma of the tea to weaken and produce an undesirable odor. The findings can provide a reference for the change in aroma during the storage of jasmine tea and provide the best storage time (3 years) in terms of jasmine tea aroma. [ABSTRACT FROM AUTHOR]

Grain Rain Period (GRP), one of the 24 solar terms in China, signifies a crucial phase for the transformation of tea quality, especially for Lu'an Guapian (LAGP) tea. During GRP, LAGP teas showed 3 distinct aroma profiles, each spanning 3-4 days. Specifically, the sensory evaluation result revealed that LAGP tea exhibited stronger flowery and fresh aromas in the early phase, with the soybean-like aroma significantly intensifying as the harvest period progressed during GRP. Furthermore, the key contributors to the aroma profile and its variation during GRP were identified as indole, δ-decalactone, geraniol, linalool, decanal, jasmone, (E)-β-ionone, benzeneacetaldehyde, dihydroactinolide, nonanal, octanal, (E)-isoeugenol, (E,E)-2,4-nonadienal, 4-ketoisophorone, (E,Z)-2,6-nonadienal, and 1-octen-3-one. Additionally, we proposed a binary blending strategy using sensory evaluation with the methods of triangle test and normal distribution fitting to predict the blending threshold accurately. This study elucidated the dynamics of LAGP tea aroma during GRP and offered insights for tea blending optimization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this study, the stems (ST) and leaves (LT) isolated from Large-leaf yellow tea (LYT) were used for sensory evaluation and quantitative analysis of flavor metabolites by sensomics and flavoromics. The results showed that the flavors of ST and LT in LYT were significantly different, and ST had stronger roasty and nutty aroma and sweet taste, which was mainly due to the accumulation of higher theanine and soluble monosaccharides in ST, and provided more substrates for the production of more pyrazine by the Maillard reaction; whereas LT contributed to the mellow and thick taste quality of LYT, and the abundance of catechins and caffeine were the main reason. The metabolic patterns of flavor metabolites indicated that the flavor differences between ST and LT were mainly due to biological metabolism in tea plants. This study provides the selection of raw materials for LYT in the future and product development of tea stems., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)