Verification of the geographical origin of European butters using PTR-MS

• Published in: Journal of food composition and analysis 2009-03, Vol.22 (2), p.169-175
• Main Authors: Maçatelli, Melina, Akkermans, Wies, Koot, Alex, Buchgraber, Manuela, Paterson, Alistair, van Ruth, Saskia
• Format: Article
• Language: English
• Subjects: analytical methods; aroma; Biological and medical sciences; Butter; chemical composition; Classification; Direct mass spectrometry; European butter; flavor; food; Food analysis; Food composition; food grades; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Geographic origin determination of food; geographical variation; headspace; Headspace analysis; least squares; mass spectrometry; Methods of analysis, processing and quality control, regulation, standards; Milk and cheese industries. Ice creams; odor compounds; Partial least square-discriminant analysis; PLS-DA; product grading; Proton transfer reaction-mass spectrometry; provenance; PTR-MS; reaction-mass-spectrometry; spectral analysis; sweet cream butter; Volatile compounds; volatile fatty acids
• ISSN: 0889-1575; 1096-0481
• DOI: 10.1016/j.jfca.2008.10.009

In the present study, proton transfer reaction-mass spectrometry (PTR-MS) in combination with partial least square-discriminant analysis (PLS-DA) was evaluated as a method for the prediction of the origin of European butters. Eighty-three commercial butters from three European regions were subjected to headspace analysis using PTR-MS. Data were collected for the mass range m/z 20–150 using a dwell time of 0.2 s mass −1, resulting in a cycle time just under 30 s. The log transformed headspace concentrations of the masses were subjected to PLS-DA in order to estimate classification models for the butter samples. One model predicted the region of origin; a second set of models predicted dichotomously whether or not a butter originated from a particular EU country. The performance of each model was evaluated by means of a 10-fold double cross validation procedure. For 76% of the butters the region of origin was predicted correctly in the cross validation. The success rate of the countries, averaged over all dichotomous models, was 88% but large differences between countries were observed. Additional work is required to study the underlying factors that determine the geographical differences in butter volatile compositions.