Growing concern to increase life expectancy has promoted several studies in the field of nutrition, especially those on food and their effects on the human body. Assays have been performed to improve their nutritional quality. In fact, there is considerable interest in encouraging development of new ingredients, with the innovation in food products and the establishment of new market niches for these ingredients. The global market for functional foods is growing and always envisages new products with functional technological and physiological characteristics. The petitsuisse cheese is a product of high nutritional value, rich in calcium, phosphorus and fat-soluble vitamins, with a high percentage of milk proteins, coupled to excellent digestion and assimilation by the human body. Current assay describes the production of a petit-suisse cheese to which was added the probiotic Lactobacillus casei BGP 93, and determines the physical, chemical and microbiological viability of lactobacilli in cheese during storage period. Levels of protein, fat in the dry extract, moisture and pH were analyzed for physical and chemical parameters; likewise, detection of coliforms, Staphylococcus, Salmonella, Listeria monocytogenes, and yeasts and molds was performed for microbiological parameters; monitoring of the viability of Lactobacillus casei BGP 93 during its life time was conducted. The petit-suisse cheese proved to be a good vehicle for the addition of probiotic microorganism. Lactobacillus casei remained viable during shelf life even with decreasing pH, and may be considered a functional product during 30 days of storage.