104C-21 |
Surface treatment of fresh-cut lettuce with acidic electrolyzed water to extend shelf life |
H. WANG1, H. FENG1, and Y. Luo2. (1) Dept. of Food Science & Human Nutrition, Univ. of Illinois, Urbana-Champaign, 382-D Agriculture Engineering Science Bldg., 1304 W. Pennsylvania Ave., Urbana, IL 61801, (2) Produce Quality & Safety Lab., USDA-ARS-Beltsville Argricultural Research Center, 10300 Baltimore Ave., Bldg. 002, Rm. 117, Beltsville, MD 20705 Fresh-cut (minimally processed) vegetables have gained increasing popularity owing to their convenience and high nutritional value. However, the fresh-cut process accelerates product deterioration in color, firmness and flavor. Moreover, wounded surfaces provide favorable conditions for microbiological growth. Therefore, adequate control strategies during storage of fresh-cut produce should minimize nutritional and sensorial loss, and microbiological concern. Proper handling, use of effective sanitizers, low temperature storage, and modified atmosphere packaging are the main methods of reducing rapid degradation of the fresh-cut vegetables. The objective of this study was to examine the effectiveness of acidic electrolyzed water in reducing food safety risk and extending shelf life of fresh-cut lettuce. Acidic electrolyzed water (AEW) with low chlorine concentration was generated with a TOYO AEW generator. Cut iceberg lettuce (2X2 cm2 ) was dipped in treatment solutions, i.e., AEW, chlorine solution, alkaline water, and tap water, with a sample to solution ratio of 1:10 for 4 min. After the wash, the samples were spun to remove excess surface water. Samples, 150g each, were packaged into semi-permeable bags to create optimum modified atmosphere conditions and stored at 35°F for 18 days. Texture, color, total aerobic bacterial count, and coliform count were analyzed. Organoleptic properties of the products also were evaluated. The results showed that the AEW and chlorine solution treatments resulted in a 1-log reduction for aerobic plate count and 0.5-log for coliform count. During the 7 days, physical and sensorial parameters did not show significant changes. The microbial growth rate was much higher for the control than for the samples treated with AEW and chlorine solution at 35°F. After 7 days, discoloration and browning began to appear, but the texture had no significant loss. These results suggest that the quality of fresh-cut lettuce can be maintained at 35°F after treatment with low chlorine acidic electrolyzed water.
Session 104C, Fruit & Vegetable Products: Vegetables (Processed)
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