18D-34 |
|
W.-T. KIM1, T.-E. Chang1, J.-M. Paek1, D. Chung1, T. Suzuki2, and I.-S. Shin1. (1) Faculty of Marine Bioscience and Technology, Kangnung National University, Gangneung, 210-702, South Korea, (2) Division of Marine Life Science, Hokkaido Univ., Hakodate, 041-8611, Japan Electrolyzed oxidizing water (EOW) has been known to possess strong bactericidal activity. The bactericidal action of its ice has also been demonstrated, and recently the ice has been applied to pathogen control on fresh produce. In the fishery industry, crushed ice is frequently used for preserving product freshness during transportation and in market places. The EOW-ice could be more effective in the preservation than ordinary ice due to its higher antimicrobial activity. The objective of this study was to examine the effects of EOW-ice on inhibiting seafood-related pathogenic and spoilage bacteria and on preserving the freshness of saury, oyster, and shrimp. The antimicrobial ice was generated at -80oC using EOW containing 50 ppm of active chlorine. The bactericidal effect of the ice was examined against Pseudomonas flourescens, Pseudomonas putida, Bacillus subtilis, Escherichia coli O157:H7, Vibrio vulnificus, and Vibrio parahaemolyticus. Saury, oyster, and shrimp were stored with the ice in expanded polystyrene containers at 20oC. The numbers of aerobes and coliforms on the sample surfaces as well as the amounts of volatile basic nitrogen (VBN) and trimethylamine (TMA) in the samples were determined periodically. The tap water ice was used as a control. Our results showed that the populations of all the tested bacteria except Bacillus subtilis were significantly reduced when 500 ml of bacterial suspensions were treated with 5.0 g of crushed EOW-ice for more than 30 s. In the presence of EOW-ice, the numbers of aerobes and coliforms were reduced by 2.0 - 3.0 log CFU/m2 and the generation of VBN and TMA was dramatically suppressed for all the three tested fishery products. The results suggest that the use of EOW-ice, compared with the use of ordinary ice, can be a more effective way to ensure the freshness and safety of fishery products vulnerable to microbial contamination.
Session 18D, Food Microbiology: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |