Dynamic Instrumental and Sensory Methods Used to Link Aroma Release and Aroma Perception: A Review

Abstract

Perception of flavor is a dynamic process during which the concentration of aroma molecules at the olfactory epithelium varies with time as they are released progressively from the food in the mouth during consumption. The release kinetics depends on the food matrix itself but also on food oral processing, such as mastication behavior and food bolus formation with saliva, for which huge inter-individual variations exist due to physiological differences. Sensory methods such as time intensity (TI) or the more-recent methods temporal dominance of sensations (TDS) and temporal check-all-that-apply (TCATA) are used to account for the dynamic and time-related aspects of flavor perception. Direct injection mass spectrometry (DIMS) techniques that measure in real time aroma compounds directly in the nose (nosespace), aimed at obtaining data that reflect the pattern of aroma release in real time during food consumption and supposed to be representative of perception, have been developed over the last 25 years. Examples obtained with MS operated in chemical ionization mode at atmospheric or sub-atmospheric pressure (atmospheric pressure chemical ionization APCI or proton-transfer reaction PTR) are given, with emphases on studies conducted with simultaneous dynamic sensory evaluation. Inter-individual variations in terms of aroma release and their relevance for understanding flavor perception are discussed as well as the evidenced cross-modal interactions.

Drivers of the In-Mouth Interaction between Lupin Protein Isolate and Selected Aroma Compounds: A Proton Transfer Reaction–Mass Spectrometry and Dynamic Time Intensity Analysis

“…Establishing a direct link between in vivo aroma release and perception is challenging due to food matrix effects and interindividual differences, which often play a significant role. , …”

“…Establishing a direct link between in vivo aroma release and perception is challenging due to food matrix effects and Table 2 interindividual differences, which often play a significant role. 18,49 Reactivity and Position of the Carbonyl Group on the Alkyl Chain. The impact of the reactivity and the location of the carbonyl group (keto group) were investigated by comparing the two C9-length aroma compounds: nonanal and 2-nonanone.…”

“…Unsurprisingly, discrepancies between methodologies are common, 18 , 22 , 23 , 50 with many analytical techniques lacking the sensitivity of the human nose. 18 In Figure 2 A,B, hexanal and nonanal were not detected in unflavored samples in vivo .…”