Modified atmosphere packaging of 'Sweet Heart' cherries: fruit quality and bioactive compounds

In order to delay the typically rapid postharvest deterioration of these fruit, it is advisable to implement technologies allowing for a better preservation of their eating quality and content in health-promoting compounds during storage and commercial distribution. The purpose of this study was therefore to assess the suitability of different modified atmosphere (MA) packaging materials on eating and functional quality of sweet cherry fruit. Fruit were hand-picked at commercial maturity, packed immediately in different MA plastics (Xtend, Long life and perforated polyethylene) and stored at 0 degrees C during 15 or 30 days. Samples were analysed 0 and 3 days thereafter for a number of parameters indicative of commercial, organoleptic and nutritional quality. Results indicate that MA packaging allowed in general better preservation of commercial quality of fruit. Firmness, soluble solids content and surface red colour were higher in Xtend packages, after 15 days storage; however, there hadn't differences at the end of shelf-life period after 30 days storage. On the other side, MA packaging led higher content of phenolics, anthocyanins and antioxidant capacity than in unpacked fruit, during shelf-life period after 30 days storage. Furthermore, Xtend-packed samples also scored higher when sensory acceptability was assessed by means of a consumer panel, after 15 days storage. Higher acceptability scores were associated mainly to more intense perception of firmness, sweetness and characteristic flavour. Biochemical analysis showed that lowered O-2 concentrations within the packages did not induce any significant onset of fermentative processes within the fruit (ethanol and acetaldehyde content, and PDC and ADH enzymatic activity).