Reducing the incidence of under-skin browning in Honey Gold mango (Mangifera indica L.) fruit.

摘要

Honey Gold mango is a relatively new cultivar in Australia, with an appealing skin colour and sweet fibre-free flesh. However, fruits can develop under-skin browning (USB), which appears several days after packing as a distinct bruise-like discolouration under the epidermis and can affect large areas of the fruit surface. Anatomy of USB and the impact of post-harvest fruit handling conditions on the disorder was determined. Starch accumulated around the resin canals and discoloured cells in the affected area, with no visible change to the cuticle or epidermis. Delays of 1 d at ambient temp. (27-35 degrees C) before packing, and 2 d at 18-20 degrees C (after packing), before placing fruits at 12-14 degrees C and road transportation, reduced the incidence of USB by 83% compared to placing fruits at 12-14 degrees C within 13 h of picking. The incidence of USB was 88-100% higher in fruits cooled to 12-14 degrees C within 13 h of picking, then commercially road-freighted for 4 d at 12-14 degrees C, than in fruits held under similar temp. conditions, but not road-freighted. Wrapping each fruit in bubble-wrap to minimise direct contact with other fruits, with the plastic insert, or with the cardboard tray, reduced the incidence of USB by 84% after road-freight compared to not using bubble-wrap. Results suggest that USB is a unique disorder of mango skin associated with a rapid post-harvest reduction in temp., from high ambient temp. to 12 to14 degrees C, and with physical damage during road-freight.