Control of Decay in Modified-atmosphere Packages of Sliced Apples using 2-Nonanone Vapor

A flow-through vapor exposure system was developed to evaluate the effects of 2-nonanone vapor on the decay of apple slices inoculated with Penicillium expansum Link, and Botrytis cinerea Pers. Treatments with 2-nonanone at 130 to 300 μL (STP)/L of air at 23°C retarded growth of fungi on PDA. At 300 μLL^-1, fungal growth was completely suppressed; however, it re-grew when transferred to air. At 5°C, exposure to 50 μL.L^-1 suppressed, and at 100 μL.L^-1 apparently killed, P. expansum on PDA and apple slices. For P. expansum at 5°C, only 25% of the 2-nonanone used at 23°C was needed. Physiological damage occurred on the peel of treated apples.