Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/5/2006
Publication Date: 8/10/2006
Citation: Zhou, B., McEvoy, J.L., Luo, Y., Saftner, R.A., Feng, H., Beltran, T. 2006. Application of 1- methylcyclopropene reverses the deleterious effect of exogenous ethylene on fresh-cut watermelon and controls microbial growth. Journal of Food Science. 71:1-5. Interpretive Summary: Whole and fresh-cut watermelon sales have increased steadily in the last few years. However, major losses occur due to the deleterious effects of exposure to ethylene (a gaseous compound that causes premature ripening) during transport and storage of the fruit. Better understanding of the effects of ethylene and inhibitors of ethylene on whole and fresh-cut watermelons can reduce postharvest losses. In this paper we report that the gaseous chemical 1-methylcyclopropene (1-MCP) can dramatically reduce watermelon tissue damage and microbial growth associated with ethylene exposure. This information will be of use to the fresh and fresh-cut produce industry in improving the quality and shelf life of watermelon products.
Technical Abstract: The effects of exogenous ethylene, 1- methylcyclopropene (1-MCP), or both on microbial growth on watermelon fruit and watermelon slices were investigated. Freshly harvested seedless watermelons (Citrullus lanatus Thunb. Matsum and Nakai, variety Sugar Heart) were treated with 0, 0.5 or 1 ppm 1- MCP, 10 ppm ethylene, 1- MCP + ethylene, or air. Fruits were processed into watermelon slices and stored at 5° C. At days 0, 6 and 12 post processing, watermelon slices were sampled for the microbial analysis. Treatment with 10 ppm ethylene alone significantly increased the population of aerobic bacteria, lactic acid bacteria, and yeasts and molds on watermelon slices compared to the control and resulted in extensive juice leakage from watermelon slices. The ethylene treatment resulted in high aerobic bacterial counts throughout the flesh of intact melons compared to the controls. A treatment of 0.5 or 1 ppm 1-MCP prior to treatment with ethylene alleviated the deleterious effects of ethylene. Extending the time from harvest to 1-MCP treatment increased the population of aerobic bacteria, but had no effect on the growth of lactic acid bacteria or yeasts and molds.