Giorgini Elisabetta, Notarstefano Valentina, Foligni Roberta, Carloni Patricia, Damiani Elisabetta
Department of Life and Environmental Sciences, Università Politecnica delle Marche, Via Brecce Bianche, I-60131 Ancona, Italy.
Department of Agricultural, Food and Environmental Sciences-D3A, Università Politecnica delle Marche, Via Brecce Bianche, I-60131 Ancona, Italy.
Foods. 2023 Dec 28;13(1):109. doi: 10.3390/foods13010109.
ATR-FTIR (Attenuated Total Reflectance Fourier Transform InfraRed) spectroscopy, combined with chemometric, represents a rapid and reliable approach to obtain information about the macromolecular composition of food and plant materials. With a single measurement, the chemical fingerprint of the analyzed sample is rapidly obtained. Hence, this technique was used for investigating 13 differently processed tea leaves (green, black and white) all grown and processed in European tea gardens, and their vacuum-dried tea brews, prepared using both hot and cold water, to observe how the components differ from tea leaf to the in-cup infusion. Spectra were collected in the 1800-600 cm region and were submitted to Principal Component Analysis (PCA). The comparison of the spectral profiles of leaves and hot and cold infusions of tea from the same country, emphasizes how they differ in relation to the different spectral regions. Differences were also noted among the different countries. Furthermore, the changes observed (e.g., at ~1340 cm) due to catechin content, confirm the antioxidant properties of these teas. Overall, this experimental approach could be relevant for rapid analysis of various tea types and could pave the way for the industrial discrimination of teas and of their health properties without the need of time-consuming, lab chemical assays.
衰减全反射傅里叶变换红外光谱（ATR-FTIR）结合化学计量学，是一种快速可靠的方法，可用于获取有关食品和植物材料大分子组成的信息。通过单次测量，就能快速获得被分析样品的化学指纹图谱。因此，该技术被用于研究13种在欧洲茶园种植和加工的不同加工方式的茶叶（绿茶、红茶和白茶），以及它们用热水和冷水冲泡的真空干燥茶汤，以观察从茶叶到杯中的冲泡液，其成分有何不同。在1800 - 600厘米区域收集光谱，并进行主成分分析（PCA）。对来自同一国家的茶叶及其热泡和冷泡茶汤的光谱轮廓进行比较，突出了它们在不同光谱区域的差异。不同国家之间也存在差异。此外，观察到的因儿茶素含量引起的变化（如在约1340厘米处），证实了这些茶的抗氧化特性。总体而言，这种实验方法可能对各种茶叶类型的快速分析具有重要意义，并可为茶叶及其健康特性的工业鉴别铺平道路，而无需进行耗时的实验室化学分析。
