Author/Authors :
el-dengawy, r. a. damietta university - fac. of agric. - food industries dept., Damietta, Egypt , sharaf, a. m. damietta university - fac. of agric. - food industries dept., Damietta, Egypt , el-kadi, s. m. damietta university - fac. of agric. - agricultural microbiology dept., Damietta, Egypt , mahmoud, eman a. , Egypt , baidoon, eslam s. damietta university - fac. of agric. - food industries dept., Damietta, Egypt
Abstract :
The imported frozen (Mackerel) Scomber scombrus was evaluated for the changes of its quality during freezing storage at -18ºC for four months and its compliance with the Egyptian standard specifications. It was found that the protein, lipid and ash contents decreased during the storage period. Furthermore, moisture slightly increased during the storage period. The results also indicated that the samples did not exceed the permissible limits of total nitrogen as determined by the Egyptian Organization for Standardization and the quality of production. Microbiological examination showed a significant decrease [P 0.05] in the total bacterial count between the first and fourth months of storage. Staphylococcus spp. was detected in the first and the second months of surface examination, being 104.70 cfu×10^3 /g and 2.74 cfu×10^3 /g, respectively. In addition, Salmonella was detected in the first month of surface examination. E. coli and Clostridium were absent in all examined samples. Fourteen different bacterial isolates were isolated from all samples. Twelve isolates were isolated from staph 110 medium and two isolates were found on the SS agar medium. Twelve isolates were coccoid shaped bacteria and 2 isolates were spore forming long rods. All isolates were gram positive. Two isolates were spore forming and twelve isolates were non-spore forming. Six isolates were considered as Staphylococcus sp. and another six isolates were considered as Micrococcus sp. the last two isolates were considered as Bacillus sp.
