Wine is, in its composition, a solution of water, various organic and inorganic compounds that are subdued to change and deterioration. Today, it is known that microorganisms are present in almost every wine and that there are useful microorganisms (acidic fermentation bacteria). Wine contains ingredients that prevent development of microorganisms (alcohol, acids). Properly nourished wine contains SO2 which stops development of microorganisms. Wine degradation is caused by poor wine production process or insufficient care. Wine production is a very complex process. It may happen that irregular procedures and mistakes that have been made during grape processing, lead to wine defects and shortcomings. In different conditions and developmental stages, various chemical and biochemical reactions occur, and thus organoleptic properties and chemical composition of the wine changes. Diseases are caused by microorganisms, bacteria, yeasts and molds, and the wine changes the taste, the smell, the color and the limpidity. With regular hygiene of rooms, dishes and machines, proper grape processing, controlled fermentation of the grape juice, we prevent the occurrence of disease and deficiency. Wine filtration just before bottling is the final phase in wine making.