Simultaneous instrumental and sensory analysis of volatile release from gelatine and pectin/gelatine gels

Release of volatiles from gels during eating was measured by monitoring the volatile composition of breath, using on-line atmospheric pressure chemical ionisation–mass spectroscopy (APCI–MS), and by simultaneous sensory time–intensity (TI) evaluation. The time–release (TR) and TI curves were very similar, suggesting a simple relationship between changes in volatile concentration over the eating time course and the intensity of volatile perception. Analysis of the Tmax values (time to maximum intensity) showed that the ratio between the Tmax for the sensory and instrumental data (sensory Tmax/instrumental Tmax) varied with the instrumental Tmax, such that at low Tmax values the ratio was >1.0 and, as Tmax increased, the ratio decreased to below 1.0. This trend suggested that with short eating events there may be a lag in perception after the maximum breath stimulus concentration. Conversely if the eating process took longer, sensory adaptation might occur. ©