For over 4000 years, lactic acid bacteria are used to make many products, including fermented dairy products (cheese, yogurt...). Fermentation gives food flavor and distinctive texture, can keep better and also provides some nutritional and health benefits. If this practice was the intuitive origin, its scientific basis are now better understood. Waste collection will be available to households that are sorted by the following ground and subjected to spontaneous fermentation several physico chemical and microbiological analyzes are periodically established, we raise in this paper follow microbiological counts in order to see the effects lactic acid bacteria on the fate of other pathogenic bacteria and in order to achieve purification and characterization of isolates. Analyzes to characterize bacterial strains are by physicochemical methods, biological tests for the specification of lactic strains for the selection of seeds, the most acidifying and more efficient, that would be fundamental to the preparation of a close which is subsequently used in a controlled fermentation. As noted below strains Nos. 9 and 7 are the most acidifying this brings us to the preparation of a close under good conduct controlled fermentation.