Influence of cultivar and osmotic dehydration time on aroma profiles of muskmelon (Cucumis melo, cv reticulatus Naud.) spheres

Among several factors affecting the osmotic dehydration process, the raw ma terial characteristics play a fundamental role. As aroma is one of the majo r determinants of fruit quality, the influence was studied of both the cult ivar and the processing time of dewatering-impregnation-soaking (DIS) on th e aroma profiles of muskmelon spheres, in order to optimise the technique a s a pretreatment to further processing. Muskmelon cultivar Mirado and Pony, manually cut into 28 mm diameter spheres, were subjected to osmotic dehydr ation at 25 degreesC for 1, 2, 4 and 6 h in a 60% (wt/wt) sucrose syrup. Bo th muskmelon cultivars showed higher uptake of soluble solids when compared with other fruit and there was a higher water loss in cultivar Mirado than cultivar Pony during the whole process. The aroma profile of melon cultiva r Pony was less modified by DIS, indicating a better suitability for this t ype of pretreatment. 'Positive' aroma compounds did not decrease in cultiva r Pony, and 'negative' ones significantly increased only after 6 h of DIS. Possible differences in tissue structure could account for the different be haviour of the two cultivars. (C) 2001 Elsevier Science Ltd. All rights res erved.