Effects of heat treatment on post-harvest quality of mango fruits

Mango fruits (Mangifera indica L.) were harvested at the pre-climacteric st age. Fruits were immersed in 38, 46, and 54 degrees C heated water for 30 m in Drier to storage at 5 degrees C for 2, 4, or 6 weeks in carton boxes. Af ter storage, they were kept at 20 degrees C for one week to simulate shelf life. Fruits were evaluated for total soluble solids, titratable acidity be ta-carotene content, reducing sugars, starch content, pulp colour, and visi ble symptoms of chilling injury. Chilling injury index and appearance were influenced significantly by dip temperature and storage period. Total solub le solids was higher in heated fruit at 38 degrees C compared to heated fru its at 46 and 54 degrees C, while titratable acidity was significantly high er in fruit heated at 54 degrees C. Maximum inhibition of carotenoid format ion occurred in non-heated and heated fruit at 54 degrees C. Heated water h ad a significant effect on pulp colour parameters (lightness, hue, and chro ma). High correlation coefficients were observed between carotenoid content and colour attributes b*, hue, and chroma. The results of this study indic ate that mango tolerance to chilling temperatures may increase after pre-st orage heat treatments at temperatures below 54 degrees C.