Combined proton and deuterium NMR - A simple, smart and versatile technique for authentication of fats and oils
11th Global Summit on Food & Beverages
September 22-24, 2016 Las Vegas, USA

Armin Hermann

Institut für Lebensmittelchemie und Arzneimittelprüfung, Germany

Posters & Accepted Abstracts: J Food Process Technol

Abstract:

Stable isotope analysis is a well-known tool for testing food authenticity. Generally, its application demands for complex instrumentation (NMR and IRMS) and laborious sample preparation. In contrast to established procedures (e.g. SNIFNMR), a high degree of simplification is achieved by a smart combination of proton and deuterium NMR spectra. For testing the authenticity of vinegars, this strategy has already been applied successfully. However, this technique has not been applied for testing the authenticity of fats or oils, although the measurement for these commodities is further simplified as there is almost no sample preparation. For lipids, the technique allows to obtain the average deuterium concentration of up to 8 different molecular moieties simultaneously. In a preliminary study, the deuterium ratio of 53 samples of fats and oils from different biological origins {plants (27), land animals (20) and sea animals (6)} were analyzed and evaluated. Data analysis of the deuterium isotope ratios revealed a clear differentiation for fats originating from plants or animals respectively. The moiety with the highest discriminating power is the α-(CH2)-group (i.e. the methylene group directly attached to the carboxyl group of the fatty acid). An example for application is testing edible fats (e.g. margarine) on their precursors. The results of this study may also be of interest for mechanistically studies in biochemistry. Furthermore, the technique is of general use, as it can be applied to virtual all compounds.

Biography :

Email: armin.hermann@yahoo.co.uk