Enantiomeric separation and compound specific stable isotope analysis

11 A fast and simple method for authenticating raspberry flavors from food products was developed. The two enantiomers 12 of the compound (E)-α-ionone from raspberry flavor were separated on a chiral gas chromatographic column. Based on 13 the ratio of these two enantiomers the naturalness of a raspberry flavor can be evaluated due to the fact that a natural 14 flavor will consist almost exclusively of the R enantiomer, while a chemical synthesis of the same compound will result 15 in a racemic mixture. 16 27 food products containing raspberry flavors where investigated using SPME-chiral-GC-MS. We found raspberry jam, 17 dried raspberries and sodas declared to contain natural aroma all contained almost only R-(E)-α-ionone supporting the 18 content of natural raspberry aroma. Six out of eight sweets tested did not indicate a content of natural aroma on the 19 labelling which was in agreement with the almost equal distribution of the R and S isomer. Two products were labelled 20 to contain natural raspberry flavors but were found to contain almost equal amounts of both enantiomers indicating a 21 presence of synthetic raspberry flavors only. Additionally, two products labelled to contain both raspberry juice and 22 flavor showed equal amounts of both enantiomers, indicating the presence of synthetic flavor. 23