Identification of lactic acid bacteria in traditional curd in the Sudanian zone of Chad

In Chad, milk and its products are consumed by many people including the curd in its various forms. This product still called "Laban Rayib" has also an important role in the labor market. In fact, these different types of curds are made without real respect basic standards of technology and hygiene. This situation will be improved if lactic ferments are well identified and taking into account their synergy. The Scientists can propose to the producers the formulas to improve the curds. However the studies in this field are rare to have reliable scientific information. It is in this context that this study was conducted to identify lactic acid bacteria in milk curd to provide scientific data needed for improve the fermented product. Thus, one hundred samples of 100 ml were collected from producers due to 10 samples / producer. The analyses were performed in the laboratory of Hygiene and Industry of Food of Origin Animal (HIDAOA) of the Inter-States School of Sciences and Veterinary Diseases (EISMV) of Dakar in Senegal and at the Veterinary and Zoo Technical Research Laboratory of Farcha (LRVZ) in Chad. The culture media used are M17 broth and agar, broth and de Man, Rogosa and Sharpe (MRS) for the search of these lactic acid bacteria. The identification of bacteria isolated and purified was made using the API 50 CH galleries biochemical, 20 STREP and software WEB API galleries. The lactic species identified are Lactoccocus diacetylactis , Streptococcus thermophilus , and Lactococcus lactis subsp lactis . Isolated Lactobacilli are Lactobacillus plant arum, Lactobacillus helveticus , Lactobacillus fermentum , Lactobacillus brevis and Lactobacillus acidophilus . The results of this work could be a good tool for information and awareness to improve the characteristics of the curd.