Real-time fingerprinting of the dynamics of green tea volatiles by ion mobility spectrometry for aroma assessment and discrimination
Real-time fingerprinting of the dynamics of green tea volatiles by ion mobility spectrometry for aroma assessment and discrimination
复制标题
通过离子迁移光谱法对绿茶挥发物的动态进行实时指纹分析，用于香气评估和辨别
DOI：
10.1016/j.lwt.2020.109751
复制
发表时间：
2020-09-01
影响因子：
6
通讯作者：
Zhou, Qinghua
中科院分区：
文献类型：
--
作者：
Li, Jia;Hua, Jinjie;Zhou, Qinghua
香气是决定茶叶品质的关键因素。茶叶香气由许多挥发性物质组成，具有高度的动态性。因此，重要的是生成捕获由在相对短的时间段（诸如在茶冲泡期间）内发生的茶挥发物的时间变化所反映的动态信息的综合模式。本文建立了一种高时间分辨的正光电离离子迁移谱（PP-IMS）方法，用于茶叶挥发物动态变化的实时指纹图谱分析。系统考察了不同电离源对分析性能的影响。基于最小湿度干扰确定最佳采集时间窗口。作为概念的证明，这种方法被应用到五种不同类型的绿色茶香气的评估和比较。结合化学计量学工具，利用“动态”指纹图谱准确区分了五种香气。RV系数（0.20-0.63）和鉴别结果表明，与传统的“静态”指纹图谱相比，“动态”指纹图谱包含了更多的茶叶挥发性成分信息，提高了茶叶香气的鉴别能力。本研究为茶叶香气的综合评价提供了一个有用的工具，这将有助于茶叶产品的质量评价和控制。
Aroma is a crucial factor determining the tea quality. Tea aroma consists of numerous volatiles and is highly dynamic. Thus, it is significant to generate a comprehensive pattern capturing the dynamic information reflected by the temporal changes of tea volatiles occurring in a relatively short period such as during tea brewing. Herein, a highly time-resolved positive photoionization ion mobility spectrometry (PP-IMS) approach has been developed for real-time fingerprinting of the dynamic changes of tea volatiles. The influences of different ionization sources on the analytical performance were systematically explored. The optimal acquisition time window was determined based on the minimum humidity interference. As a proof of concept, this approach was applied to the assessment and comparison of five different types of green tea aromas. In combination with chemometric tools, five types of aromas were accurately distinguished by using their "dynamic" fingerprints. The RV coefficients (0.20-0.63) and discrimination result showed that the "dynamic" fingerprints contained additional different information on tea volatiles and enabled an improved discrimination of tea aromas, compared to the conventional "static" fingerprints. This study provides a useful tool towards a comprehensive assessment of tea aromas, which is promising to facilitate the quality evaluation and control of tea products.