Characterization and identification of microflora from soaked cod and respective salted raw materials

The microflora of soaked cod products from salted and dried salted cod were identified to the species level by the Viteke automated identification system using the Gram-positive identification (GPI) and Gram-negative identification plus (GNI+) cards, and a cluster analysis was performed to determine the similarity among the strains. Within the Gram-positive bacteria, Staphylococcus epidermidis, S. hominis, S. warneri, S. haemolyticus, S. simulans and S. saprophyticus were found. Regarding Gram-negative, Stenotrophomonas maltophilia, Vibrio alginolyticus, Pasteurella haemolytica, Enterobacter agglomerans, E asburiae, E cloacae, Pseudomonas putida, P. fluorescens, Shewanella putrefaciens, Morganella morganii, Actinobacillus urea, Acinetobacter lwoffi/junii and non-fermentative bacilli were identified. Several species found in the soaked products were also isolated from the salted and dried salted cod. Thus, despite of the low water activity of these products, the mentioned strains were able to survive. Some of these, had the ability to produce H2S and/or presented decarboxylase activity, therefore it is probable that the growth of these bacteria during soaking might contribute to the spoilage of soaked cod. Aeromonas hydraphila and A. caviae were not isolated from the soaked food, but from the raw material (dried salted cod). Their presence might constitute a potential hazard, especially considering that these foods may be eaten raw. (C) 2003 Elsevier Science Ltd. All rights reserved.