MATURITY AND WATER-LOSS EFFECTS ON AVOCADO (PERSEA-AMERICANA MILL) POSTHARVEST PHYSIOLOGY IN COOL ENVIRONMENTS

The influence of cold storage, increasing fruit maturity and water loss on the ripening physiology of 'Fuerte' avocado was investigated. Fruit cold stored for 28 d at 5.5-degrees-C always subsequently ripened faster than non-stored fruits of a similar maturity. Non-stored fruit showed an expected decrease in ripening time with increasing maturity. In cold stored fruit the relationship between ripening time and maturity was less clear. Cold stored fruit lost less water during ripening than non-stored fruit of similar maturity, but lost water faster than non-stored fruit. Increasing maturity reduced the total amount of water lost during ripening. Cold storage increased the incidence of mesocarp discoloration which became more severe with increasing fruit maturity. Passive water infusion into fruit had no effect on the rate of fruit ripening (and water is obviously not involved as a 'ripening trigger') but totally inhibited the manifestation of postharvest browning disorders.