Evaluation of Key Aroma Compounds in Processed Prawns (Whiteleg Shrimp) by Quantitation and Aroma Recombination Experiments

In our previous study on the aroma compounds of heated prawn meat, the main odorants in blanched (BPM) and fried prawn meat (FPM), respectively, were characterized by means of gas chromatography-olfactometry and aroma extract dilution analysis. In this follow-up study, these aroma compounds were quantified by means of stable isotope dilution assays, and odor activity values (OAV; ratio of concentration to odor detection threshold) were calculated. Results revealed 2-acetyl-1-pyrroline and (Z)-1,5-octadien-3-one as the most potent odor-active compounds in both prawn samples. In FPM, as compared to BPM, higher OAVs were determined for 2-acetyl-1-pyrroline, 2-acetyl-2-thiazoline, 3-methylbutanal, 3-(methylthio)propanal, phenylacetaldehyde, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2,3-diethyl-5-methylpyrazine, and trimethylpyrazine. Aroma recombination experiments corroborated that the overall aroma of the blanched as well as the fried prawn meat, respectively, could well be mimicked by the set of key odorants quantitated in this study.