Steam treatment reduces the skin microflora population on deheaded and eviscerated whole catfish

This study tested the efficacy of steam exposures for 0, 30, 60, 90, and 12 0 s on reducing skin microflora of whole deheaded and eviscerated catfish. Microbiological analyses of skin were performed after treatment and on days 2, 4, 6 8, 10 and 14 days of storage at 4 degrees C. Catfish skin samples were examined for total (APC), coliform (CPC), and psychrotrophic (PPC) pla te counts. Results indicated that as steam treatment duration increased gre ater reduction of catfish skin microflora was achieved Mean bacterial count s determined on steam-treated catfish skins were significantly (P < 0.05) l ower than controls at all sample times Steam treatment for 120 s was the mo st effective treatment modality, with APC, PPC and CPC lower than control b y 2.3, 3.5 and 3.4 log cfu cm(-2) after 4 days of storage at 4 degrees C. S kin APC and CPC were reduced below the limit of defection (1.8 log cfu cm(- 2)) following a 30-s exposure, and remained at this level until day 4 of st orage at 4 degrees C. Skin PPC were reduced by 2 log cfu cm(-2) following 1 20-s steam exposure. Steam application to whole deheaded eviscerated catfis h may prove useful to sanitize catfish skin prior to further processing int o valuable consumer products. (C) 1999 Academic Press.