Performances of the barrel kiln used in cottage industry for fish processing and effects on physicochemical characteristics and safety of smoked fish products.

BACKGROUND: In the traditional food sector, the smoking process and smoking-drying process are widely used to increase the shelf-life of seafood products. The smoking process and smoking-drying process are mainly performed using barrel kiln and wood as fuel in many West African countries. The present study evaluated the performances of the barrel kiln and its effects on physicochemical characteristics and safety of smoked fish (SF) and smoked-dried fish (SDF). Twelve follow-ups were conducted with three experimental processors and 24 samples of fish collected at different steps of processing were analyzed in a laboratory using standard methods. RESULTS: The extreme values of combustion temperature recorded during the smoking process (456.4 °C) and smoking-drying process (482.8 °C) were higher than 450 °C, the temperature at which wood pyrolysis generates polycyclic aromatic hydrocarbons (PAHs). Smoked fish were highly contaminated with PAHs, and showed maximal levels of benzo[a]pyrene (52.7 µg kg-1 ) and PAH4 (i.e. sum of benzo[a]pyrene, chrysene, benzo[b]fluoranthene and benz[a]anthracene) (290.9 µg kg-1 ) exceeding the European Union limits by about 25-fold. After smoking of Scomber scombrus and smoking-drying of Cypselurus cyanopterus, no significant differences were recorded for lipid, protein and biogenic amine contents between fresh and processed fish, even if the histamine content of both fish exceeded the limit fixed by the European Union regulation. CONCLUSION: The results obtained in the present study showed that smoked fish and smoked-dried fish produced using barrel kiln and wood fuel are highly contaminated by PAHs. Therefore, there is a need to improve the preservation practices of raw fish and smoking conditions to limit the contamination of end-products by PAHs known to be carcinogenic components for humans and to ensure consumer safety. © 2021 Society of Chemical Industry.

Consumption and physico-chemical characteristics of smoked and smoked-dried fish commonly produced in South Benin and contribution to recommended nutrient intakes.

The work aims to assess the consumption and the physico-chemical characteristics of smoked fish and smoked-dried fish commonly produced and consumed in the South Benin. The consumption data were obtained from a survey involving 250 consumers, conducted in selected production localities of the Southern part of Benin, where 36 samples of smoked fish and smoked-dried fish were collected. The highest protein contents (dry matter) were recorded in Cypselurus cyanopterus (85.1 ± 2.3%) and Sphyraena barracuda (84.5 ± 4.2%), while the highest lipid contents were recorded in Scomber scombrus (39.0 ± 9.2%) and Ethmalosa fimbriata (22.1 ± 6.3%). Smoked and smoked-dried fish produced in South Benin contained 0.1%-12.5% (of total fatty acids) eicosapentaenoic acid and 0.1%-33.2% docosahexaenoic acid, which are the most abundant omega 3 polyunsaturated acids in these fish products. The median consumption of smoked fish (60.2 g/day) and smoked-dried fish (18.2 g/day) contributed for 112% (281.1 mg) and 72% (180.4 mg), respectively, to the adult daily recommended intake of sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (250 mg/day). The daily protein intake related to the consumption of smoked fish and smoked-dried fish corresponded to 36% and 24%, respectively, of the recommended intake suggested by European Food Safety Authority (0.8 g/kg.bw/day).

Microbiological characteristics of smoked and smoked-dried fish processed in Benin.

This study aimed to assess the microbiological status of smoked fish (SF) and smoked-dried fish (SDF) processed in Benin, and to identify the contamination factors associated with these products. A total of 66 fish samples, including fresh fish and processed fish, were randomly collected from different processing sites and markets for microbial characterization using standard methods. The aerobic mesophilic bacteria (AMB) density varied from 2.9 to 9.5 Log10 CFU/g. Enterobacteriaceae, Escherichia coli, Bacillus cereus, Clostridium perfringens, yeasts, and molds were present in 63.9%, 27.8%, 55.6%, 58.3%, 61.1%, and 77.8% of samples, respectively, while no Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus were found. The majority (66.7%) of SF samples and 22.2% of SDF samples were not compliant with the acceptable limit of <7.0 Log10 CFU/g recommended by the Health Protection Agency for AMB, whereas the Enterobacteriaceae counts exceeded the recommended level of 4.0 Log10 CFU/g for 50% of SF and 5.6% of SDF samples. Likewise, 38.9% of SF samples were not compliant for E. coli. Microbiological hazard analysis of practices allowed to identify the sensitive steps where hygiene measures need to be emphasized for an improved quality control.