Chemical Characteristics and Microbial Quality of Guedj a Traditional Fermented Fish from Senegal

The present study aimed to estimate the chemical characteristics and microbial quality of traditional Senegalese fermented fish produced locally and known as Guedj which was prepared by using three types of fish: fatty fish (Machoiron or catfish or Arius latisculatus), medium fat fish (Capitaine or Pseudotolithus brachygnatus) and lean fish (Sompatte or Pomadasys jubelini). Samples were collected from three production areas located in Dakar, Thies and Fatick regions. The other samples were from Institute of Food Technology (ITA). Samples from ITA were used as controls. Results of test samples have shown significant differences in most chemical and microbial parameters when compared with those of the controls. Mean values of moisture contents, pH, TVB-N and NaCl of Guedj samples from the three production areas were significantly higher than those of the control (collected at ITA). Specifically: 1) moisture contents from Machoiron, Capitaine and Sompatte were 58, 42.60 and 26.90%, compared to controls 42.48, 35.60 and 24.40 %, respectively. 2) pH values were 6.56, 6.38 and 6.35 compared to controls 6.42, 6.28 and 6.28 respectively. 3) TVB-N values were 228.3, 308, and 334.8 compared to controls 155.4, 236.5, and 204.8 respectively. 4) NaCl contents were 10.75, 10.78 and 7.77 compared to controls 8.20, 7.80 and 6.56 respectively. Microbiological analyses showed that all test samples displayed higher microbial loads when compared to the control groups. We noted the presence of yeasts and molds, coliforms, pathogenic staphylococci, clostridia and lactic acid bacteria (LAB) in some of Guedj samples, but salmonella and Vibrio parahaemolyticus were absent. In conclusion the poor quality of the fermented fish, Guedj were mainly due to use of low quality spoiled fish as raw material, unhygienic procedures, the lack of standard operating procedures and adequate equipment, combined to improper salting and drying.