Fruit Ripening and Disease Control in Bananas and Mangoes by Hot Water Treatment
Antonio L. Acedo Jr.1, Lilia L. Millan2 and Marilou M. Benitez3
The efficacy of hot water dip (HWD) as a simple, non-chemical postharvest treatment to inhibit banana and mango fruit ripening and disease development was determined. Freshly harvested mature-green fruits were used. After HWD, the fruits were cooled in tap water before storage at ambient conditions (26-31oC, 65-88% RH). HWD as 10-min treatment minimized disease incidence and retarded ripening of ‘Latundan’ (Musa AAB) and ‘Saba’ (Musa BBB) bananas and ‘Carabao’, mangoes but did not affect softening of ‘Indian’ mangoes, a variety usually consumed firm green. The indirect 47-49oC HWD (enclosing fruits in plastic bag during dipping) was the most promising for inhibiting banana ripening and anthracnose (Colletotrichum musae) or finger rot (Botryodiplodia theobromae and Fusarium ssp.) disease. HWD inhibition of diseases was comparable to that of the fungicide treatment (500ppm benomyl, 3min). In ‘Indian’ mango, the direct 48-50oC HWD was sufficient to inhibit anthracnose (C. gloeosporioides). In ‘Carabao’ mango, increasing the water temperature from 51-33oC to 54-56oC delayed ripening further. Pre-heating in 40oC water prior to HWD did not additionally retard ripening but improved the inhibitory effect of 51-53oC HWD on anthracnose and stem-end rot (Diplodia natalensis) development. HWD had no adverse effects on other quality attributes of bananas and mangoes.
1Postharvest Technology Laboratory, Department of Horticulture, Leyte State University, Visca, Baybay, Leyte 6521-A