The aimed of this study showed the possibility
to evaluate the quality and find out the degree of contamination of local fresh
fish meats, this fish its common name in Yemen is (Gahsh), and its scientific
name is (Lethrinus elongatus). The samples taken from Taiz city
markets [Republic of Yemen], and stored at room temperature, the
microbiological, physical and chemical changes were followed by examination of
samples during storage at zero time as (control samples) and every day. The
results illustrate the microbial contamination increasing and the evaluation of
the physical and chemical characteristics quality were decreased and
deteriorated during storage. As well as isolation seventeen species of bacteria
identified and classification to six groups of  
Bacillus   spp   obtained  
from   prior   samples. On other hand the population of
Aerobic, Anaerobic, Spore formers, Yeast and Moulds Enterobacteriaceae, Coli
form groups, Salmonella spp, Staphylococcus 
spp, Streptococcus  spp,
Clostridium  spp,
Bacillus  spp, Enterococcus spp and  Proteolysis bacteria, were increased by the
following percentages: 68.56%, 43.2%, 26.75%, 28.82%,  49.59%, 16.66%,  15.00%, 
30.53%,  24.24%,16.92%, 14.52%,
14.49%, and  50.50% respectively. The
nutrition chemical characteristics i.e [Moisture, Protein and Fat content] were
decreased as following percentages: 0.81 %, 0.54% and 0.63 % respectively, and
the Carbohydrate content increasing as 43.97%. The chemical indicates for
spoilage i.e [Total volatile nitrogen, Tri
methyl amine, Ammonia nitrogen, Thiobarabituric acid, Total energy value and
Water holding capacity] increasing as following percentages: 147.87%, 114.74%,
82.55%, 62.57%, 1.43 % and 16.36% respectively. The pH value and Bound water
decreased as 7.00% and 3.89% respectively, as compared
with the control samples.