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 (Mugil cephalus), and farm water fish (Tilapia nilotica) fish (50 of each) were collected from Sharkia governor during summer of 2014 to investigate the incidence of Vibrio spp. as well as studying the effect of heat treatments (frying and roasting). The obtained results revealed that incidence of Vibrio spp. in fresh water 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. fluvialis 4 (8%), V. mimicus 7(14%), V. alginolyticus 2(4%), and V. damsel 2(4%). In farm water fish Vibrio spp. were 17(34%) while the overall incidence in the samples was V. parahaemolyticus 1(2%), V. vulnificus 3(6%), V. fluvialis 3(6%), V. mimicus 5(10%), V. alginolyticus 2(4%), and V. damsela 3(6%). Ten pieces of fish fillet (100g of each and 5 pieces for each treatment) were used to study the effect of frying with cotton seed oil (1900 C) for 10 minutes 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 were decreased by 98.2% and 100%, respectively.