Characterising volatiles in tea (Camellia sinensis). Part II: Untargeted and targeted approaches to multivariate analysis

Using headspace-solid phase microextraction (HS-SPME) and solvent-assisted flavour evaporation (SAFE), the volatiles in five common types of teas (white, green, oolong, black and pu-erh teas) were extracted for GC-MS/FID analysis, and the major compounds in each tea were identified. Subsequently, untargeted and targeted approaches were used in principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) for further data interpretation. Confidence levels using the targeted approach were generally higher for sample classification. Therefore, this study offers a better methodology to improve the existing knowledge of tea volatiles.