Investigation of some pathogenic bacteria and heavy metal presence in sevruga (Acipenser stellatus) caviar of Azerbaijani origin

Sevruga caviar's microbiological and chemical quality, a world-renowned delicacy, is very important to consumers. The study aims to determine the safety of sevruga caviar, produced from Acipenser stellatus sturgeon, which ranks among the world's leading caviar producers, in terms of consumer health by examining its possible microbiological contamination and heavy metal levels. Within the scope of the study, a total of 60 caviar samples were examined from three different regions of Azerbaijan: Mingeçevir, Neftçala, and Baku. The caviar samples were analysed for microbiological parameters, including coliform bacteria, Escherichia coli, sulphite-reducing Clostridium spp., Staphylococcus aureus, yeast and mould counts, and the presence of Salmonella spp., in accordance with relevant ISO standards. Toxicologically, heavy metal levels such as mercury, lead, and cadmium were examined in the samples using an ICP-MS device. According to the results obtained, the coliform group bacteria, Escherichia coli, sulphite-reducing Clostridium spp., Staphylococcus aureus, yeast and mould counts were found to be below legal limits or undetectable. Salmonella spp. was not detected in any of the caviar samples. When examining the heavy metal analysis results of Sevruga caviar samples, only one sample (1.7%) had a lead level of 0.4 mg/kg, exceeding the maximum acceptable limit (0.3 mg/kg). Although the cadmium level in one Sevruga caviar sample was found to be as high as 0.01 mg/kg, this value is below the acceptable limit for cadmium (0.05 mg/kg). On the other hand, the mercury level in all caviar samples was found to be below the detection limit (0.5 mg/kg). Accordingly, it was determined that microbiological hygiene conditions were good during the sevruga caviar production process and that the products did not pose a risk to consumer health. On the other hand, based on the heavy metal findings obtained, it is necessary to implement integrated management systems based on a monitoring and control mechanism for caviar samples. In conclusion, while it has been determined that the consumption of sevruga caviar, one of the world's most expensive delicacies, is suitable from a microbiological and toxicological perspective, it is considered important for sustainability that microbiological and toxicological control, monitoring, and continuous improvement practices continue to be meticulously implemented for the production of healthy and high-quality sevruga caviar. September 2025, 125 pages. Keywords: Food safety, Heavy metal contamination, Microbiological quality, Sevruga caviar.