Results of our research work are of great importance in the food and health area, with special contribution in the sector of products, which can increase the competitive position of the economy (functional food, food and feed supplements, OTC drugs). In addition, acquired knowledge improves the quality of education of the scientists and experts. Most of our results lead to the direct applicative value. Namely, the modulation of the fatty acids composition of the butter gives a product low on saturated fatty acids and high of unsaturated fatty acids. The collection of phages and host cells enables rapid detection and effective sanitation of phage contamination in cheese plants. Moreover, Lactobacillus gasseri LF221 and K7 are novel probiotic strains both applicable either in food or pharmaceutical industry, with the potential of using K7 even as a protective starter culture as it prevents the late blowing of cheeses.