Postharvest handling of plums (Prunus salicina Lindl.) at 10 °C to save energy and preserve fruit quality using an innovative application system of 1-MCP

Abstract

1-Methylcyclopropene (1-MCP) inhibits softening in plums, making it a candidate for a postharvest strategy of storing fruit at higher than normal storage temperatures to avoid chilling injury (CI) while providing energy and cost savings. This hypothesis was tested by exposing different Japanese plum (Prunus salicina Lindel.) cultivars to 0.5μLL−1 1-MCP at 0°C for 24h. Following 1-MCP treatment, fruit were stored at 0 or 10°C for 10, 20, or 30d, respectively. A new application technology was tested by applying 1-MCP during forced-air cooling (FAC), reducing the application duration from 24 to 6h without affecting treatment performance. This new 1-MCP application system is compatible with current postharvest handling, rendering it easily adopted by the tree fruit industry. 1-MCP had no detrimental effect on consumer acceptance of low-acid plums ripened properly prior to consumption, but it reduced the acceptance of high acidity plums. Thus, 1-MCP use on plums should avoid cultivars with high acidity and/or plums picked early when fruit have titratable acidity of 0.9% or more. 1-MCP–FAC treatment followed by storage at 10°C is a promising new methodology to avoid chilling temperatures and provide considerable energy savings without reducing postharvest life and consumer quality of low-acid plums. Our results encourage testing this new technology at commercial scale to accurately quantify energy savings and consumer reactions for specific operations and markets.