Whither on the Vine?
PTR-MS analysis of VOCs in Pinot Noir can pin down its origin
How well do you know your Pinot Noir? A new method could provide a rapid “fingerprint” of the volatile organic compounds (VOCs) in this silky smooth, complex little number…
When it comes to wine analysis, gas chromatography-mass spectrometry (GC-MS) is a regular at the table, offering accurate analysis and differentiation of VOCs. The word on the ‘vine is, there are faster alternatives – but the presence of ethanol can reduce sensitivity.
A team of New Zealand researchers from the Department of Food Science, University of Otago, NZ, hit the vineyards in an attempt to achieve rapid differentiation of wines from different sites, while maintaining sensitivity (1). The team had already sampled several wines for analysis with GC-MS at two different stages during the winemaking process (2) – immediately before being barreled, and after being aged in barrels for six months. In the current study, the VOC profile of each sample was differentiated by proton-transfer reaction mass spectrometry (PTR-MS; Ionicon Analytik) combined with manual headspace dilution – to minimize the effects of the ethanol.
The results? In the published paper, the authors conclude that PTR-MS analysis of wine, while less able to identify specific compounds than GC-MS, “may be a useful technique for rapid VOC fingerprinting to discriminate samples from different geographical origins.” They add that “the similarities and differences expressed in the wines’ VOC profiles may help winemakers to reveal the potential of individual vineyard sites to produce wines of certain character.” In other words: using PTR-MS may well make life easier (and analysis quicker) for winemakers and those fighting wine fraud…which can only be good news for all the oenophiles out there.
- C Schueuermann et al., “PTR-MS volatile profiling of Pinot Noir wines for the investigation of differences based on vineyard site”, J Mass Spectrom, [Epub ahead of print], (2017) PMID: 28598532.
- C Schueuermann et al., “GC-MS metabolite profiling of extreme Southern pinot noir wines: Effects of vintage, barrel maturation, and fermentation dominate over vineyard site and clone selection”, J Agric Food Chem, 64, 2342-2351 (2016).
A former library manager and storyteller, I have wanted to write for magazines since I was six years old, when I used to make my own out of foolscap paper and sellotape and distribute them to my family. Since getting my MSc in Publishing, I’ve worked as a freelance writer and content creator for both digital and print, writing on subjects such as fashion, food, tourism, photography – and the history of Roman toilets.
