Aroma volatiles during non-climacteric melon ripening and potential association with flesh firmness

© 2018 International Society for Horticultural Science. All rights reserved. The aroma volatiles of a near-isogenic line of melon SC10-2 with differential textural traits were sampled during ripening up to 18 d at 20.5°C and 88% relative humidity starting after 4 days. A ¿Piel de Sapo¿ parental was tested as control. Flesh samples were extracted and the aroma volatiles of filtered juice with calcium chloride salt added were extracted by solid phase microextraction and further analyzed by gas chromatography coupled to mass spectrometry. Data were fully integrated with Chemstation and by deconvolution analysis, and compound identification confirmed by linear retention indices according to the literature. The aroma volatile profile consisted of 149 compounds and fourteen of them were unidentified. Aldehydes were noticeable in the profile (22 compounds), and also ketones (22), acetate (15) or non-acetate (23) esters, or alcohols (18). Alkanes presented 9 compounds, 12 compounds were sulfur compounds, and 17 were assigned to other groups while 9 were unidentified The aromas found at a higher concentration in the samples were hexanal, ethyl acetate and acetophenone. Aroma volatiles generally decreased from harvest up to 12 d postharvest or remained constant, while after this senescence period most of them relatively increased though a few of them decreased. Changes during ripening of hexanal or 2-ethylhexan-1-ol were very similar to those found in flesh firmness and they could be used as biomarkers for melon storage at room temperatures.