Influence of postharvest curing treatment on the synthesis of the volatile flavor components in sweetpotato

Postharvest treatments can significantly alter quality attributes of harvested crops. We assessed the impact of curing (7d at 29.4°C, 95%RH), of two sweetpotato cultivars [Ipomoea batatas (L.) Lam.] on volatile flavor chemistry. Volatile extracts were collected during baking using a cold solvent (MeCl 2 ) trap, sampling at harvest and after curing. Odorants were discerned by olfactory assessment of GC peaks with the identity of critical compounds determined by GC-MS. Of 46 compounds identified, 38 were odor-active. Curing had a pronounced effect on aroma intensity and quality. Uncured roots yielded only 37% (cv. 'Jewel') and 12% ('GA90-16') of the total amount of odor-active volatiles of cured roots and had substantially depressed aromas. Certain compounds were not obtained from freshly harvested roots (i.e., only 22 of 38 compounds were present in 'GA90-16' and 34 of 37 in 'Jewel'). Curing appears to enhance the synthesis of α- and β-amylase which in turn facilitates starch hydrolysis during baking and formation of monosaccharides that act as precursors for critical volatile flavor components.