Effect of smoking on the microbiological quality of horse mackerel (Trachurus trachurus) processed and marketed by artisanal fishermen from Vilankulos, Mozambique

Abstract

Smoking is one of the fish conservation techniques used by some artisanal fishing communities. Horse mackerel is a fish widely traded and consumed in Mozambique. This study aimed to evaluate the effect of smoking on the microbiological quality of horse mackerel sold in district Desse in Vilankulos. Twelve samples were collected and analyzed for following microbiological parameters (total viable microorganisms, total coliforms, thermotolerant coliforms, Escherichia coli, Salmonella spp., Staphylococcos aureus, Vibrio cholerae and Vibrio parahaemolyticus). The total viable microorganisms were quantified by the NMKL method and the total coliforms, fecal coliforms, and Escherichia coli were quantified by the MPN method. Statistical analysis were performed using the SPSS program, and data were submitted to the normality test using the Shapiro-Wilk test at a significance level of 5%. The results showed the existence of significant differences in the amount of aerobic microorganisms between frozen horse mackerel (3.59 ± 0.87 CFU/g) and smoked horse mackerel (2.39 ± 0.88 CFU/g), total coliforms (0.22 ± 0.53 CFU/g), and (0.06 ± 0.19 CFU/g), respectively, and thermotolerant coliforms (0.12 ± 0.25 CFU/g) and (0.06 ± 0.19 CFU/g), respectively. Smoked horse mackerel had less contamination compared to the frozen fish. There was no significant growth of other microorganisms analyzed.