36E-51

M. M. SALAMEH¹, H. Yang², S. A. Ibrahim¹, and C. W. Seo¹. (1) Food Science and Nutrition Program, North Carolina A&T State Univ., Dept. of Human Environment and Family Sciences, 171-B Carver Hall, Greensboro, NC 27411-1064, (2) Dept. of Human Environment and Family Sciences, North Carolina A&T State Univ., 161 Carver Hall, Greensboro, NC 27411

Contamination of fresh produce with pathogenic bacteria is a major concern in the food industry. A minimum of 2 log unit reduction of the initial microbial count was recommended by governmental agencies. Oxine (chlorine dioxide) has shown to improve the microbiological safety of fresh fruits and vegetables. The objective of this study was to evaluate the efficacy of oxine alone or in combination with warm water in improving the microbio-logical quality of green leafy vegetables. Turnip green, spinach and mustard were obtained from local sources and submerged for 5 minutes in: 1) tap water, 2) warm water at 45° C or 50° C, 3) oxine solution at 20 or 40 ppm, and, 4) warm water followed by oxine. Sample homogenates were analyzed for total bacterial counts, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus. The degree of disinfection was monitored in terms of log microbial counts reductions versus type of treatment. Our sresults indicated that tap water treatment could remove 50% of the initial microbial loads. Both 45^o C and 50^o C warm water treatments can further reduce microbial loads. The inhibitory effect of microbial growth was greatest by the activated oxine aqueous solution at all concentrations among treatments (p<0.05). There was no difference in disinfection effect between oxine (40 ppm) alone and the combination of oxine (40 ppm) and warm water. E.coli and Salmonella typhimurium were more susceptible to inactivation by oxine than Staphylococcus aureus. Oxine at 40ppm was very effective in reducing pathogenic bacteria in green leafy vegetables.

Session 36E, Fruit & Vegetable Products: General
8:30 AM - 12:00 PM, Monday AM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana