Delayed Fruit Harvest and Ripening Temperature Effects on Post-Harvest Quality of ‘Reed’ Avocado

Maturity at harvest is an important factor that influences storage life, fruit response to postharvest treatments and the final fruit quality. This study was initiated to investigate the effects of increasing fruit maturity on post-harvest quality of avocado fruit ripened at different temperature regimes. ‘Reed’ avocado fruit were harvested at different maturity stages (early, mid and late) on a monthly interval and stored at 6°C for 28 days. After storage, fruit were subjected to different ripening temperatures (16, 21 and 25°C) and evaluated for post-harvest diseases and disorders. Internal chilling injury increased with maturity and ripening temperature. Higher temperatures induced higher anthracnose incidences during early and mid-harvest compared with late harvest time. Vascular browning and stem-end rot incidences were high on fruit ripened at 16°C than 21 and 25°C. Fruit lightness  increased with ripening time regardless of ripening temperature during early harvest, but remained constant during mid and late harvest while Hue angle (h 0 ) and Chroma (C*) values were slightly reduced during ripening. Fruit ripened at 25°C had the highest respiration rate and reached a climacteric pick earlier than fruit ripened at 21 and 16°C.  Fruit firmness and weight loss were high and rapid at 25°C followed by 21 and 16°C regardless of the harvesting time. Generally, fruit maturity influenced the response of fruit to ripening temperatures with late harvested fruit being less sensitive to cold storage disorders. Furthermore, higher temperatures were found to enhanced ripening and were conducive to postharvest disease.