Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: December 10, 2002
Publication Date: February 17, 2002
Citation: Hua, W., Hao, F., Luo, Y. 2004. Surface treatment of fresh cut lettuce with acidic electrolyzed water to extend shelf life. Annual Meeting of the Institute of Food Technologists. Abstract.
Fresh-cut vegetables have gained increasing popularity for their convenience and high nutritional value. Unfortunately, minimal processing accelerates product deterioration in color, firmness and flavor. Moreover, wounded surfaces provide favorable conditions for microbiol growth. Therefore, adequate control strategies during fresh processing should minimize nutritional and sensory loss as well as microbiological concerns. Proper handling, use of effective sanitizers, low temperature storage and modified atmosphere packaging are the main methods of reducing rapid deterioration of fresh-cut vegetables. The objective of this study was to examine the effectiveness of acidic electrolyzed water (AEW) in reducing food safety risks and extending the shelf-life of fresh-cut lettuce. Cut iceberg lettuce (4cm2) was immersed in one of the treatment solutions (AEW, chlorine solution, alkaline water or tap water) with a sample to solution ratio of 1:10 for 4 min. After washing, the remaining water was removed from the samples by spinning. Samples (150) were packaged in a bag under modified atmosphere conditions and stored at 1-2°C for 18 days. Texture, color, total aerobic counts and coliforms were analyzed and organoleptic properties were evaluated. Results showed that AEW and chlorine solution treatments resulted in a 1-log reduction for total aerobic plate counts and 0.5-log for coliforms. After 7 days, physical and sensory parameters did not show significant changes. The microbiol growth rate was much higher for the control than lettuce treated with low chlorine concentration AEW or a chlorine solution at 1-2°C. Discoloration and browning began to appear, but there was no significant loss in texture following storage. These results suggest that the quality of fresh-cut lettuce can be maintained at 1-2°C after treatment with low concentration chlorine AEW.