Evaluation of postharvest infiltration of calcium to delay the ripening of avocados

Postharvest vacuum infiltration of calcium into mature but unripe Hass and Fuerte avocados obtained from 80 growers in the 3 major growing districts in Australia over 2 seasons delayed the time to ripen compared with untreated fruit; but the magnitude of the response varied. Hass fruit from 66% of growers in the Murray Valley showed a significant delay in ripening and the average increase in fruit from all growers was 45% over that of untreated fruit. The response of Fuerte fruit was similar between districts, with an average delay in ripening time of about 30% and with fruit from 60% of growers having a significant increase. Hass fruit from North Queensland and northern New South Wales gave the lowest average delay in ripening of about 10% and an increased delay was significant for fruit from 25% of growers. The quality of ripe Hass fruit was not affected by calcium infiltration, whereas a slight decrease in the quality of Fuerte fruit was observed.