1-MCP Prolongs shelf life

A post-cutting treatment of 1-methylcyclopropene (1-MCP) was applied to ready-to eat salad vegetable mixes (RTE-SVM) consisting of lettuce, carrots and cucumber to determine its potential in maintaining the storage quality. The responses of different varieties of lettuce were also compared. Minimally-processed lettuce (Corelle, Romaine, and Iceberg varieties), Japanese cucumber, and carrots were prepared and packed in PET trays then sealed with PVC cling wrap film. 1-MCP gas was injected in the packs to have a final concentration of 1ppm and 3ppm inside the RTE-SVM packs. The packs were stored in a cold room (5-8°C) until they became unacceptable as a whole, but the shelf life and limit of marketability of the packs were set when the packs reached an average VQR of 6 (Fair, moderate defects). Headspace gas analyses (oxygen, carbon dioxide, and ethylene) and visual evaluation (visual quality rating, lettuce wilting and yellowing, carrots discoloration, and cucumber water-soaking) were performed. The RTE-SVM prepared with Corelle lettuce has the best response to the 1-MCP treatment, having the highest average VQR, lowest incidence of wilting and yellowing and carrots discoloration when treated with 3 ppm 1-MCP. The RTE-SVM packs prepared with Iceberg and Romaine lettuce, on the other hand, can be treated with 1ppm 1-MCP to reduce the incidence of lettuce wilting and yellowing and carrots discoloration in the packs. Furthermore, it was determined that the RTE-SVM prepared with Corelle, Romaine, and Iceberg lettuce can be stored for 8, 10, and 5 days, respectively, at 5-8°C before reaching the limit of marketability.