Determination of nutrient composition, amino acid, fatty acid content and microbiological quality values of fish meal produced in Çanakkale province

Fish meal is produced by processing and drying fish that are not suitable for human consumption or waste left over from the fishing industry. Fishmeal has become one of the main by-products of the fishing industry. It is used as a source of protein and amino acids in feed. Fish meal has an important place in the nutrition of fish and other carnivorous and omnivorous pets. The quality of fish meal attracts attention as a very sensitive issue, especially since it is added to the rations of poultry and fish. They can create a suitable reproduction environment for microorganisms due to their high level of nutritional content and the processes applied during production. In the study, fish meals obtained from a private fish meal factory in Çanakkale province was used. In addition to the Yellow-fin and Skipjack fish species, three groups called Mixed (a group that includes Yellow-Fin, Skipjack and other different fish) have been created. The current study was carried out to determine the quality of fish meals obtained from different fish, through nutrient, amino acid and fatty acid profiles, mineral substances, microbiological analyses, yeast and mold analyses, and microscopic analyses. It was determined that the moisture rate was between 1.58-4.16%, the dry matter rate was between 95.84-98.42%, the raw ash rate was between 18.44-20.18%, the crude protein ratio was between 61.00-61.70%, the crude fat ratio was between 9.36-11.40%, the organic matter ratio was between 72.25-78.86%, and the HCl acid-insoluble ash ratio was between 0.96 and 0.98% in the study. It was determined that the highest values of Lysine, Histidine, Valine, Alanine and Aspartic amino acids belonged to the Skipjack group as, respectively, 4.69, 1.60, 3.02, 3.88, 5.73 and the Mixed group was statistically equivalent to the Skipjack group. Yellow-fin group were found to be statistically low in terms of these values (p<0.05). Other amino acids were not found to be statistically significant (p>0.05). Fatty acids C16:0, C16:1, C18:1, Omega 3, EPA and PUFA were found to be highest in the yellow-fin group and lowest in the skipjack group, and the difference between the groups was found to be statistically significant (p<0.001). While Omega 6 fatty acids were highest in the yellow-fin group, Skipjack and Mixed groups (containing Yellow-fin Skipjack and other different fish) were found to be similar. The highest values of Calcium, Phosphorus, Potassium and Magnesium were found in the Yellow-fin group and were determined as 6.06, 3.71, 0.86 and 0.27, respectively (p<0.01). According to the results of microbiological analysis, the number of Coliform bacteria was determined as 1.4x10² in the Skipjack group. Coliform Bacteria Count and E. coli (Cob/g) of Yellow-Fin and Mixed fish meals were similarly found to be <10. Salmonella was not detected in any fish meal. Microbiological analysis results show that all fish meals comply with the standards of the Communiqué on Microbiological Criteria. Amino acids were not found to be statistically significant (p>0.05). Fatty acids C16:0, C16:1, C18:1, Omega 3, EPA and PUFA were found to be highest in the yellow-fin group and lowest in the skipjack group, and the difference between the groups was found to be statistically significant (p<0.001). While Omega 6 fatty acids were highest in the yellow-fin group, Skipjack and Mixed groups (containing Yellow-fin Skipjack and other different fish) were found to be similar. The highest values of Calcium, Phosphorus, Potassium and Magnesium were found in the Yellow-fin group and were determined as 6.06, 3.71, 0.86 and 0.27, respectively (p<0.01). According to the results of microbiological analysis, the number of Coliform bacteria was determined as 1.4x10² in the Skipjack group. Coliform Bacteria Count and E. coli (Cob/g) of Yellow-Fin and Mixed fish meals were similarly found to be <10. Salmonella was not detected in any fish meal. Microbiological analysis results show that all fish meals comply with the standards of the Communiqué on Microbiological Criteria. Histamine was not detected in fish meal obtained from Yellow-Fin, Skipjack and Mixed (Yellow-Fin, Skipjack and other fish species). Therefore, the fish meals in the current study were classified as high quality fish meals from a microbiological perspective. In the current study, fish meal; Aspergillus spp., Penicillium spp., Fusarium spp. Phisiyum spp., Rhizophus spp. Fungus species and Total Yeast Colony Numbers were examined. While Fusarium spp., Aspergillus spp., Phisium spp. and Rhizophus spp. were not detected in any of the fish meal, Penicillium spp. were detected at 1.3×10⁴, 0.6×10⁴ in Skipjack and Mixed fish meal, respectively. Penicillium spp. was not detected in Yellow-Fin fish meal. Microscopic examination is needed to determine the quality of fish feed, whether it is adulterated, and the degree of contamination. Compared to other analysis methods, Microscopic analysis is a simple, fast and less time-consuming technique. It is a very suitable method, especially for pre-inspection of feed raw materials. As a result, it has been concluded that the fish meal produced in the Çanakkale region is of extremely high quality, both in terms of nutrients and microbiology, and is extremely suitable for animal nutrition.