Heat treatment injury of mango fruit revealed by nondestructive magnetic resonance imaging.
Joyce D. C., Hockings P. D., Mazucco R. A., Shorter A. J., Brereton I. M.
Author Affiliation: CSIRO Division of Horticulture, St. Lucia, Qld 4067, Australia.
Postharvest Biology and Technology 3 : 305-311
Abstract : Proton magnetic resonance imaging (MRI) was used to observe disinfestation heat treatment-induced injury in the mesocarp of ripening mango fruits (cv. Kensington Pride). The fruits were subjected to conditioning (which consisted of warming fruits wrapped in plastic film, in an incubator, to a core temperature of 37°C over 7 h) and/or heat treatment (warming unwrapped fruits in hot water to a core temperature of 47° over 1.5-2.0 h). The core temperature was maintained for 25 min. Neither conditioning nor heat treatment impaired fruit softening or skin colour change. However, heat treatment, particularly in the absence of prior conditioning, caused both skin and mesocarp disorders associated with heat stress. Injured areas were characterized by relatively low water levels (low signal intensity) corresponding to air filled cavities and islands of starchy mesocarp. Non-destructive proton MRI proved to be a sensitive method for detecting and monitoring the progress of heat treatment-induced injury in mango fruits.