The influence of harvest maturity on postharvest performance of new blush pear cultivars from Australia

Most European pear (Pyrus communis) cultivars require a cold conditioning phase after harvest to fully ripen. Few blush pear cultivars have been studied, but they appear to have long conditioning requirements. Maturity stage at harvest influences fruit postharvest behaviour, storability and final fruit quality. To determine the effect of harvest maturity on storage performance, this study investigated the new Australian blush pear cultivars ‘ANP-0118’ and ‘ANP-0131’ (referred to as ‘118’ and ‘131’, respectively) picked at different maturities (early, commercial and late) and stored for 6 storage durations (8, 12, 16, 20, 24 and 28 weeks) at -0.5°C in air. Fruit quality was assessed at harvest, immediately after removal from cold storage and after 7 days ripening at 18°C. The quality parameters measured were the index of absorbance difference (I_AD), flesh firmness, soluble solids concentration (SSC) and incidence of superficial scald. From harvest until storage removal at 28 weeks, Early ‘118’ fruit lost 36.7% firmness, commercial 35.1% and late 40.4%. In contrast, early ‘131’ fruit lost 11.6% firmness, commercial lost 6.2%, and late 6.4%, indicating that ‘131’ better maintained ‘crispness’. All storage treatments of ‘118’ dropped substantially in firmness after 7 days ripening, whereas ‘131’ remained crisp after 8 weeks storage followed by 7 days ripening. There were no significant differences in SSC throughout storage for either cultivar. ‘131’ took longer than ‘118’ to reach peak SSC and the duration required to peak differed among harvest maturities. In both cultivars, there remained significant differences in I_AD after 28 weeks. ‘118’ consistently dropped in I_AD across the 3 maturities, but ‘131’ dropped I_AD at a higher rate for later pickings. No rots or symptoms of superficial scald were found in ‘131’ fruit after storage or ripening. In contrast, ‘118’ suffered from superficial scald when stored for 16 weeks or longer.