Microbiological quality of grey-mullet roe

Area of Science:

• Food Microbiology
• Food Science and Technology
• Seafood Safety

Background:

• Greek grey-mullet roe (Mugil cephalus) is a traditional food product with growing international popularity.
• As a ready-to-eat food, its microbial quality is critical for consumer health protection.
• Traditional processing involves salting, drying, shaping, and beeswax coating.

Purpose of the Study:

• To conduct a microbiological examination of Greek grey-mullet roe before the final waxing stage.
• To identify potential bacterial pathogens and assess the adequacy of traditional processing methods for ensuring food safety.
• To evaluate the microbial load and identify specific bacterial species present in the roe samples.

Main Methods:

• Collection of 48 grey-mullet roe samples from local processors before waxing.
• Microbiological examination using selective media under aerobic and anaerobic conditions.
• Bacterial identification using Bergey's manual, Gram staining, catalase, oxidase, and biochemical tests.

Main Results:

• Pathogens including Vibrio spp., Salmonella spp., Aeromonas hydrophila, Shigella spp., E. coli, and Staphylococcus aureus were detected in 2-8% of samples.
• Micrococcus spp. and Clostridium perfringens spores were found in 16% and 35% of samples, respectively.
• Listeria species (L. innocua, L. welshimeri, L. seeligeri, L. ivanovii, L. grayi) were present in 2-10% of samples.

Conclusions:

• Traditional processing methods for grey-mullet roe appear insufficient to guarantee food safety.
• The final waxing step may not fully protect against salt-tolerant facultative anaerobes.
• Additional food safety measures are recommended during processing and marketing to mitigate consumer health risks.