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Melons are prized for their characteristic aroma, however, pre-harvest growth, stage of ripening at harvest, post-harvest processing and storage conditions lead to quality changes in fresh-cut fruit. We considered changes in metabolites and gene expression over 14 days storage to assess underlying mechanisms and identify potential quality markers. Overall, 99 volatile organic compounds (VOCs) were detected and VOC profiles discriminated between two melon seasons, cut-size, storage temperatures and storage time, although season affected their discriminatory power. Abundance of two VOCs fell rapidly and was not associated with cut size, indicating their use as markers for early changes post-processing. Non-acetate to acetate ester ratio differed between the seasons and correlated with changes in alcohol acyl-transferase ( CmAAT1 ) gene expression. Furthermore, CmAAT1 expression clustered with two ester VOCs that may be potential new products of this enzyme. Season also strongly affected post-harvest sugar content, most likely attributable to meteorological differences during growth. Storage temperature and cut size affected expression of transcription factors ERF71 , ERF106 , and TINY , whose expression generally rose during storage, probably related to increased stress. Thus, although time × temperature of storage are key factors, pre-harvest conditions and fruit processing impact significantly gene expression and aroma loss post-harvest.

Strawberries are valued for their aroma and phytochemical content. However, they have a short shelf life and storage at low temperatures to prolong shelf life affects physiological and biochemical processes in the fruit. This impacts on their use in fresh cut ready-to-eat fruit salads. To assess changes in aroma and how these are related to phytochemical content and gene expression, Fragaria x ananassa cv. Elsanta strawberries were halved and stored at either 4 °C or 8 °C for a period of 12 days. Phytochemical content was relatively unaffected whereas volatile organic compound profiles were distinct at different time points of storage. Gene expression changed significantly with storage over a 5 day period: a total of 1135 gene targets changed in expression (p < 0.05; log2 fold change >1.5) with most changes between days 0 and 5 of storage. These included genes related to stress responses, and secondary metabolism. Real time PCR was used to verify expression profiles of two genes related to VOC classes represented in the aroma, showing changes in pattern of expression during storage.

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