Use of the index of absorbance difference (IAD) as a tool for tailoring post-harvest 1-MCP application to control apple superficial scald

The aim of this study was to better define postharvest strategies to preserve apple fruit quality during storage with particular attention on superficial scald control as the result of the interaction between 1-methylcyclopropene (1-MCP) treatment and fruit ripening stage. Ripening was no-destructively defined by the "index of absorbance difference" (I<inf>AD</inf>) measured with a DA-Meter, a portable device based on visible/Near Infra-Red (vis/NIR) spectroscopy. Superficial scald incidence and total content of α-farnesene and conjugated triols (CTols), were assessed at two month intervals, among 6 months of cold storage (1°C) for three consecutive seasons in two apple cultivars, 'Granny Smith' and 'Cripps Pink'. Results demonstrated the reliability of the I<inf>AD</inf>, not just to assess fruit maturity, but also to predict scald incidence in both apple cultivars as a function of maturity and postharvest control strategy. Consequently, differential post-harvest treatments can be applied to single appropriate apple batches increasing storability and shelf-life, while reducing spoilage.