Carbonyl odorants contributing to the in-oven roast beef top note.

Among the few papers related to the gas chromatography (GC)-olfactometric determination of important odorants in cooked beef aroma, only one uses roasting conditions, but none of them investigates the appealing aroma during the cooking of the piece of meat. The present paper investigates this top note as perceived from the oven, by analyzing the oven headspace using GC-"SNIF", a GC-olfactometric technique. From the different functional classes of odorants participating in overall in-oven aroma, this first paper focuses only on the role of aldehydes and ketones, as they represent the majority of aroma compounds formed during cooking. To ascertain the identification of these odorants, a microderivatization technique was used, based on (2,3,4,5,6-pentafluorophenyl)hydrazine. The resulting hydrazones exhibit very specific mass spectrometric fragments, leading to a sensitive and specific detection. A total of 23 carbonyl compounds were shown to contribute to the roast beef top note.