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Abstract The preferences of consumers for different flavours and aromas in wine are varied and may be explained by inherent factors such as cultural background, wine education and personal taste of the wine consumer. Wine flavour, as perceived in the mouth, includes aroma compounds released through the retronasal pathway, which are shaped by interactions with saliva. Saliva and wine interactions could provide an explanation as to why wine tasters express different preferences for wine. To test this hypothesis, 13 Western and 13 Chinese experienced wine tasters were recruited. Sensory evaluation was performed in formal surroundings to acquire free description-based and perceived sensory intensity data using the Pivot® Profile and continuous scale assessment, respectively. Participants’ saliva samples were collected before the sensory evaluation and spiked into a wine sample to investigate the impact on the wine’s volatile release using comprehensive two-dimensional gas chromatography–mass spectrometry (GC × GC–MS). Saliva samples were subjected to enzyme activity assays and protein composition profiling by Tandem Mass Tag (TMT) quantitative proteomics. The wine tasters showed differences in wine flavour perception, which was supported by the difference in wine volatile release resulting from the addition of saliva. The two groups of participants did not have significant differences in total salivary protein concentrations or the amounts of esterase and α-amylase. However, statistically significant variations in the concentrations of specific proteins (proline-rich proteins (PRPs) and lipocalin-1 (LCN-1); p

Solid phase microextraction (SPME) is a convenient, effective and green sample preparation technique, offering excellent compatibility with different chromatography methods. This review presents an overview of the history of the SPME technique and its early adaptation based on reported patents, followed by some current SPME designs, and intended usage, especially for gas chromatography (GC) applications. Particular focus on quantification approaches in SPME is included, with emphases on the methodology chosen for implementation, correct performance of quantification and validation, and the calibration method. The article concludes by highlighting some innovative SPME-related techniques, some of which are chosen for their quantitative coverage of analytes and their reported applications.

An approach to online laboratory exercises for analytical chemistry students with demonstrated practical exercises through the use of remote-controlled gas chromatography (GC) instrumentation is discussed. The approach allows for a practical-based learning activity to be carried out by students who are unable to attend in-person laboratory exercises and was conducted during the COVID-19 pandemic. Learning activities focused on the operation of GC instrumentation were completed prior to a research-based analysis activity being conducted by students. At the end of this experiment, the students are expected to understand, independently operate, and learn how to achieve better separation through the manipulation of GC settings, such as split/splitless injections, carrier gas flow rate, and oven temperature, and apply principles of GC to a practical application. Additional flexibility from this approach could also be beneficial during postpandemic and/or in the circumstance where students cannot physically attend the class.