Incidence of Vibrio species in fish with special emphasis on the effect of heat treatments

Abstract

A grand total of 150 random samples of fresh water fish (Tilapia nilotica), marine water fish (Mugilcephalus), and farm water fish (Tilapia nilotica) fish (50 of each) were collected from Sharkia governorduring summer of 2014 to investigate the incidence of Vibrio spp. as well as studying the effect of heattreatments (frying and roasting). The obtained results revealed that incidence of Vibrio spp. in freshwater fish were 13 (26%)‚ the overall incidence in the samples was 4(8%) for V. vulnificus, and 2(4%),2(4%), 2(4%), 2(4%) and 1(2%) for, V. mimicus, V. fluvialis, V. damsel, V. furnissi, and V. alginolyticus,respectively. In marine fish Vibrio spp. were 24(48%), the overall incidence in the samples was for V.parahaemolyticus 5(10%), V. vulnificus 4(8%), V. fluvialis4 (8%), V. mimicus 7(14%), V. alginolyticus2(4%), and V. damsel 2(4%). In farm water fish Vibrio spp. were 17(34%) while the overall incidencein the samples was V. parahaemolyticus 1(2%), V. vulnificus 3(6%), V. fluvialis 3(6%), V. mimicus5(10%), V. alginolyticus 2(4%), and V. damsela 3(6%). Ten pieces of fish fillet (100g of each and 5pieces for each treatment) were used to study the effect of frying with cotton seed oil (1900 C) for 10minutes and roasting in oven at 1500C for 10 minutes after their inoculation with 106 cfu/g V.paraheamolyticus. After roasting and frying‚ the microbial counts of V. paraheamolyticus weredecreased by 98.2% and 100%, respectively.