枯萎是影响茶叶品质的第一个也是关键的过程,光质量是一个关键的调节因素。然而,枯萎光质(WLQ)对茶叶香气和挥发性代谢产物(VMs)转化和形成途径的影响尚不清楚。在本研究中,建立了四个WLQ来研究它们对茶香气和VM的影响。结果表明,蓝光和红光降低了草香气,改善了茶的花香和果香。基于GC-MS/MS,检测到83个VM。通过VIP,显著差异,和OAV分析,筛选了13个关键差异VM,以表征WLQ对茶叶香气的差异影响。进一步的进化和代谢途径分析表明,糖苷代谢是通过WLQ调节茶香的关键途径。蓝光枯萎显着增强糖苷水解和氨基酸脱氨,这有利于丰富花香和果味的虚拟机,如香叶醇,柠檬醛,水杨酸甲酯,2-甲基-丁醛,和苯乙醛,以及草地虚拟机的改造,例如octanal,萘,和顺式-3-己烯基异戊酸酯,从而形成茶叶花香和果香。研究结果为优质茶叶的针对性加工提供了理论依据和技术支持。
Withering is the first and key process that influences tea quality, with
light quality being a key regulatory factor. However, effects of withering
light quality (WLQ) on transformation and formation pathways of tea aroma and volatile metabolites (VMs) remain unclear. In the present study, four WLQs were set up to investigate their effects on tea aroma and VMs. The results showed that blue and red
light reduced the grassy aroma and improved the floral and fruity aroma of tea. Based on GC-MS/MS, 83 VMs were detected. Through VIP, significant differences, and OAV analysis, 13 key differential VMs were screened to characterize the differential impacts of WLQ on tea aroma. Further analysis of the evolution and metabolic pathways revealed that glycoside metabolism was the key pathway regulating tea aroma through WLQ. Blue
light withering significantly enhanced glycosides hydrolysis and amino acids deamination, which was beneficial for the enrichment of floral and fruity VMs, such as geraniol, citral, methyl salicylate, 2-methyl-butanal, and benzeneacetaldehyde, as well as the transformation of grassy VMs, such as octanal, naphthalene, and cis-3-hexenyl isovalerate, resulting in the formation of tea floral and fruity aroma. The results provide theoretical basis and technical support for the targeted processing of high-quality tea.