Comm. Appl. Biol. Sci, Ghent University, 77/3, 2012 207 INDIVIOUAL ANO COMBINEO EFFECTS OF POSTHARVEST OIP TREATMENTS WITH WATER AT 50°C, SOY LECITHIN ANO SOOIUM CARBONATE ON COLO STOREO CACTUS PEAR FRUITS S. D'AQUIN01, A. BARBERIS1, A. CONTINELLAz, S. LA MALFA2, A. GENTILE2 and M. SCHIRRAl 1 Institute of Sciencesof Food Production, National Research Council Traversa La Crucca 3, Regione Baldinca, IT-07040, U Punti, Sassari, Italy 2 Department of Agriculture and Food Science, University of Catania Via Valdisavoia 5, IT-95123, Catania, Italy Corresponding author E-mail: salvatore.daquino@ispa.cnr.it SUMMARY Objective of this study was to evaluate the effect of prestorage dip treatments at 20'C or 50·C alone or with sodium carbonate (SC)and soy lecithin (LEC),either individually or in combination, on weight losses, peel disorders, overall appearance and decay of cactus pears. Fruits were subjected to a simulated Med- iterranean fruit fly (medfly) disinfestation by cold quarantine at 2"C for 21 days followed by one week of shelf-life at 20 "C. Hot water alone was very effective in reducing peel disorders and decay both during cold storage and shelf-Iife. SCapplied at 20·C showed a weak control of decay and chilling injury, while its effectiveness significantly increased when the solution temperature was set to 50·C. LECwas more effec- tive in preserving freshness during cold storage, but after shelf-Iife decay incidence in fruit dipped in LEC at 20·C or 50·C was higher than in those dipped in water at 20·C or 50·e, respectively. Significant but moderate differences were detected among treatments in weight 1055. After shelf-Iife, fruit dipped in the heated mixture of se and LEeshowed the lowest incidence of peel disorders and the highest percentage of marketable fruit, although decay incidence was slightly higher than in fruit treated with se at 50·C. se and LECused in combination at 50· C improved fruit tolerance to chilling injury and reduced decay. Key words: cactus pears, soy lecithin, sodium carbonate, postharvest, hot water dlp, peel disorders, de- cav· INTRODUCTION Cactus pear (Opuntia ficus-indica L. Mill.) is widely cultivated in southern regions of ltalv, which after Mexico, represents the most important producer country in the world (Basile, 2001). Due to their increasing demand, the share of production destined to be exported worldwide has constantly grown in the last decade and represents an important source of income for people Iiving in rural areas where environmental conditions do not allow to culti- vate more profitable species (Basile, 2001). Unlikely, the increasing production and exporta- tion of cactus pears have not been paralleled bya concomitant development of specific post- harvest technologies. Generally packinghouse facilities developed for other crops, in particu- lar citrus fruit, have been adapted to handle cactus pears, not taking in consideration specific needs of this fruit. Cactus pears are very perishable fruits. Their high metabolic activity associated with the rela- tively high pH Iimit postharvest life at room temperature to few days both for the rapid decay of internai quality characteristics and for the high susceptibility to various pathogens, lnclud- ing bacteria, yeast and fungi. Cold storage prolongs postharvest Iife by 2-5 weeks. However fruit are susceptible to low temperature and tissues damaged by chilling injury become more prone to decay (Inglese et al., 2002). The marketing season of cactus pear in Italy starts in rnid-