Key tomato volatile compounds during postharvest ripening in response to chilling and pre-chilling heat treatments

Abstract

Mature green ‘FL 47′ tomatoes were exposed to heat (52 °C water for 5 min) and/or cold (5 °C for 4 d) before sampling at following ripening stages. Results showed that although did not cause visual injury, chilling substantially suppressed ripening process, ethylene production and respiration rate at early stages, while a slight impact was observed by heating. Most volatiles were detected at low levels before breaker stage with a burst at red stage in all treatments. Chilling and heating induced production of “green” note volatiles, especially hexenal early in fruit development. At the red stage, 11 out of 12 important aromatic volatiles exhibited significant reduction in chilled fruit compared to control, while most volatiles in heated fruit were recovered during ripening. On the other hand, a pre-chilling heat treatment alleviated the chilling-caused reduction of ethylene during ripening, which was associated with higher levels of 6-methyl-5-hepten-2-one, 2-phenylacetaldehyde, and 2-phenylethanol in red fruit.