Micro-organisms live in every part of the biosphere, and some of them are even capable of growing at low temperatures, including those below freezing point. These micro-organisms, unfortunately, are also apparent in everyday life, i.e. refrigerators, stores etc, where they collect as pathogens and contaminate foods. Therefore, although storing foods in the refrigerator is the best way to keep them safe from bacterial contamination, there are also types of bacteria that can grow in cold temperature as well as inside the refrigerators.
Most of these micro-organisms are well able to grow below temperatures of 00-20C. They can enter the refrigerator through raw and improperly packaged foods or even through an open refrigerator door by poorly cleaned refrigerator seals, or are already growing from lack of proper sanitation or warm temperature. If ingested, they can cause dangerous foodborne illnesses. Normal daily cleaning of cooker hoods, kitchens, cold stores and freezers is not enough to remove deeper dirt. Stubborn dust nests, fats, insects, fungi and invisible bacteriological contamination accumulate in places you normally cannot reach.