Abstract
The author (Ross Farrell) travelled to Switzerland to undertake a research placement at Zurich University of Applied Science (ZHAW), from September-December 2013. A Wine Australia travel grant was used to part fund the flight costs to Zurich. The balance of funding (accommodation and living expenses) was provided by ZHAW and UTAS. The research placement was conducted under the supervision of Professor Chahan Yeretzian (Head of Analytical and Physical Chemistry). Prof. Yeretzian is an expert in the application of real-time mass spectrometry, (primarily) in the coffee industry.
Summary
The application of PTR-MS to wine is complicated by the interference of ethanol with the H3O+ primary ions utilized in the standard PTR approach. However, PTR-MS can be applied using protonated ethanol clusters as reagent ions20. As this method results in complex massspectra an alternative approach is to dilute the wine headspace with N2 and then ionize using H3O+ primary ions21. This results in a simpler, faster method better suited to routine analysis. PTR-QMS was used to obtain rapid MS fingerprints of wine varietals, which were then successfully discriminated with a chemometric analysis (i.e. PCA). PTR-QMS has also been used for in vivo analysis of wine22, wine contamination16 and monitoring evolution of VOC’s during grape must cooking (used in the production of many traditional Mediterranean food and beverages)23. Recently, instrument operating conditions have been investigated as a simpler way to control the ionization moving towards quantitative (PTR) analysis of high ethanol-containing samples24.