In-vivo analysis of banana aroma by proton transfer reaction -: Mass spectrometry

We report on in-vivo breath-by-breath analysis of volatiles released in the mouth during eating of ripe and unripe banana using Proton Transfer Reaction-Mass Spectrometry (PTR-MS). The time-intensity profiles of isopentyl and isobutyl acetate, two key odour compounds of ripe, and (E)2-hexenal and hexanal, typical for unripe banana, are discussed. The questions we address is: how do retronasal aroma (nosespace, NS) and orthonasal aroma (headspace, HS) differ? Two main differences are noticed. First, the NS concentrations of some compounds are increased, compared to the HS, while others are decreased. Second, aroma in the mouth is dynamic, evolving with time. The in-mouth situation has characteristics of its own that may lead to an aromatic experience specific to the eating situation.