Linking consumer sensory acceptability to volatile composition for improved shelf-life: A case study of fresh-cut watermelon (Citrullus lanatus)

Shelf-life improvement of fresh-cut produce such as watermelon can be guided by optimizing flavor and consumer liking, while ensuring microbial quality. In this study, the impacts of postharvest processing and packaging technologies on consumer acceptability and flavor profiles of fresh-cut watermelon were evaluated. The treatments included post-cut sanitation spray (with and without), modification of the headspace gas composition (ambient and modified atmosphere), lidding film permeability (perforated and non-perforated), storage temperature (3 and 7 Celsius degree) and storage period (1, 6 and 8 d). Odor-active compounds of both fresh and stored watermelon were identified by olfactometry. Changes in key odor-impact volatile compounds were measured using solid phase microextraction-gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry. Changes in the volatile composition of samples stored at 3 Celsius degree were correlated to the consumer sensory scores for color, fresh appearance, odor, firmness, flavor, and taste. Fresh-cut watermelon packed in ambient air, sealed with non-perforated lidding film, and stored at 3 Celsius degree for both 6 and 8 d received the highest flavor and overall liking scores compared to modified atmosphere (5 %O2 and 10 %CO2). Further improvement of flavor freshness and overall acceptability was achieved when the post-cut sanitation step was removed. Results indicated that the shelf-life, as judged by overall perceived quality, can be increased from 6 to 8 d by manipulation of processing and storage conditions without compromising flavor and consumer acceptance. The study confirmed the usefulness of linking consumer acceptability to volatile measurement as a research tool to optimize product improvement