A comparison of postharvest quality of breadfruit (<i>Artocarpus altilis</i>) after disinfestation with hot air or hot water treatments
Keywords:heat treatments, fruit fly, Bactrocera tryoni, Pacific fruit fly
Breadfruit from Samoa potentially host the Pacific fruit fly (Bactrocera xanthodes) and so their export to New Zealand requires a disinfestation treatment. Heat treatments by air (HAT) or water (HWT) are common fruit-fly disinfestation treatments for tropical crops. Two breadfruit cultivars – Puou and Ma’afala – were subjected to three heat treatments, HAT-1 (minimum 47.2oC for 20 min at core), HAT-2 (49.0oC for 100 min at core) and HWT (47.2oC for 20 min at core), and an untreated control was also included. Fruit were stored for one week at 15oC followed by three days at 25oC. Disorders observed were heat damage to the skin (blackening) and increased decay on the body and stem-end. Heat damage was at an acceptably low level following HAT-1 but was unacceptable following HAT-2 or HWT. Initial results suggest that a HAT can be tolerated, but the effect of ramp rate and the potential of using a two-step HWT system should be examined.