Indicator Bacteria and Vibrionaceae Multiplication in Post-Harvest Shellstock Oysters

Abstract

Changes in the levels of indicator bacteria and Vibrionaceae were monitored in post-harvest shellstock oysters during commercial transport and during storage at temperatures of 10°C, 22°C, and 30°C. Aerobic plate counts, fecal coliforms including Escherichia coli, and Vibrionaceae including Vibrio cholerae, V. parahaemolyticus, V. vulnificus, and Aeromonas hydrophila increased in numbers in shellstock oysters during transport and storage at 22°C and 30°C. Increases in the levels of indicator bacteria were generally accompanied by increases in Vibrionaceae, but sometimes the Vibrionaceae multiplied in the absence of fecal coliform multiplication. Storage of oysters at 10°C prevented multiplication of vibrios and fecal coliforms, but not Aeromonas hydrophila.