It is very important to identify all the agents determining the exo-polysaccharides synthesis. Using a culture medium that is adequately composed as regards carbon, energy, microelements, or pH, it is possible to obtain a desirable and functional biomaterial. Polysaccharides that are secreted outside the cell (usually in the form of mucus) are very important for the food technology. Microbiological carbohydrates such as: xanthan, curdlan, pullulan, and alginate show many specific characteristics, which other plant polymers do not have at all. The function of these compounds added to food products is to keep a desired consistency level, to increase viscosity, to reduce water losses during processing and storage, and to manufacture low calories food products. Presently, they are also applied to manufacture durable and edible covers protecting food products against spoiling. In this paper, there are presented some hygienic aspects of synthesis of microbiological exo-polysaccharides that constitute a potential risk of contaminating final food products to be marketed. These substances take part in the process of forming a mechanically stable biofilm that makes it difficult to keep a required cleanness level within the food manufacturing factories. Owing to the fact that micro-organisms extra-cellularly produce polysaccharides with exactly defined structures, and they can be indicators of contaminants probably occurring in a given environment. This property may be of essential importance if seeking effective methods for higienisation of various application surfaces.