Microbial quality of fish along with the Tilapia, African catfish and Sardinella artisanal value chains in Kpong and James Town, Ghana

Abstract

Abstract. Aboagye E, Tano-Debrah K, Kunadu APH. 2020. Microbial quality of fish along with the Tilapia, African catfish and Sardinella artisanal value chains in Kpong and James Town, Ghana. Bonorowo Wetlands 10: 1-17. Fish from artisanal sources constitute the most critical animal protein in the Ghanaian diet. However, the availability and safety of fish on the Ghanaian market are unpredictable owing to potential rapid microbial growth, which results from high ambient temperatures and poor handling along the artisanal value chains. Little is known about the small-scale fish value chains and the key stakeholders' food safety knowledge and processing practices. This study aimed at mapping out the artisanal fish value chains of Tilapia (Oreochromis niloticus), African catfish (Clarias gariepinus), and sardinellas (Sardinella aurita), and assessing the food safety knowledge and handling practices of key stakeholders along the selected value chains. A survey using semi-structured questionnaires involving 93 fishers, 40 retailers, 40 processors, and 120 consumers was carried out to investigate stakeholders’ knowledge and practices of food safety along the value chain. Samples of the selected fish species were taken along their respective value chains to test for the presence of safety indicators (Salmonella, Vibrio, and Listeria species), hygiene indicators (Staphylococcus aureus and Escherichia coli), and spoilage organisms (Pseudomonas spp. and Proteus spp.). The mean scores for food safety of retailers, processors, and consumers were generally insufficient at 55%, 43%, and 67.3%, respectively. The stakeholders also scored poorly in their handling practices, with mean scores of 41.2%, 63.0%, and 58.6% for fishers, processors, and consumers, respectively. Estimated fish losses were highest at the retailer and consumer stages of the value chain, with reported injuries as high as 35 to 100%—pathogens such as Clostridium perfringens, enteropathogenic Escherichia coli, Staphylococcus aureus, Listeria spp. And Aeromonas sobria were isolated from fresh and processed ready-to-eat fish samples. Salmonella spp. and Vibrio spp. were not detected on any samples tested. Mesophilic counts ranged from 7.96 ± 0.68 to 2.95 ± 0.23 log cfu/g reported from fresh fish samples, with similarly high fecal coliform counts averaging 3.11 log cfu/g. Processed fish samples had average total counts, fecal coliform counts, and yeasts and mold counts of 3.11, 2.27, and 2.45 log cfu/g, respectively. Proteus vulgaris and Proteus mirabilis were the predominant spoilage organisms present in almost all the fresh fish samples. This study provided much-needed insight into the unsatisfactory safety and quality of artisanal fish on the Ghanaian market and the specific microorganisms associated with them along the value chain. It also established the link between the food safety knowledge and handling practices of stakeholders within the value chain and the actual quality and safety of fish on the market.