ULTRASTRUCTURAL STUDIES OF KENSINGTON MANGO (MANGIFERA-INDICA LINN) - HEAT INJURIES

Mature green 'Kensington' mango fruit were submerged in hot water at 46C until the fruit center reached 45C and then held for 30 minutes. The fruit were allowed to ripen for 7 to 10 days after the hot water treatment, and then damaged areas of skin and mesocarp tissue were prepared for observation by scanning and transmission electron microscopy. Heating-related injuries included rupturing the patterned cuticle and exocarp and exposing the underlying cells and hollow cavities (which varied in size and shape) randomly distributed within the mesocarp beneath the skin. Starch deposits still were present in the mesocarp parenchyma cells. The cell walls of damaged mesocarp parenchyma cells were convoluted and thickened in places. The injury suggested disruption of enzymes involved in carbohydrate metabolism.