Final answer:
Freezing food below -2 °C slows down or halts bacterial growth and may kill susceptible organisms. Freezing does not sterilize food, and bacteria can become active again when thawed. Proper thawing techniques and temperature control are essential to keep food safe.
Step-by-step explanation:
Freezing food has a significant impact on bacterial growth. When food is frozen, particularly below -2 °C, microbial growth is halted, and in many cases, the organisms may be killed. This is because the extreme cold impedes the cellular metabolism of the bacteria, effectively stopping their growth and reproduction. However, freezing does not sterilize food, as some bacteria can survive at these low temperatures, particularly psychrophiles which thrive in cold environmentsIt is crucial to thaw frozen food properly, as thawed foods should be handled like fresh perishables. The USDA recommends that frozen foods should be thawed in the refrigerator, in cold water changed every 30 minutes, or in the microwave, keeping the food out of temperature ranges that allow bacteria to grow.
Refrigerators and freezers are used extensively to preserve food by slowing down the processes that cause food spoilage, including bacterial growth. Even when frozen, the microbes are merely in a state of suspension and can become active once again once the food is thawed. Therefore, it's essential to maintain food storage temperatures properly: below 4 °C (40 °F) for refrigerators and below -18 °C (0 °F) for freezers. Thawing should be done in a manner that does not allow the bacteria to become active and cause spoilage or illness.Freezing food slows down bacteria growth. When food is frozen, the low temperatures inhibit microbial metabolism, significantly slowing the growth of bacteria. Freezing below -2°C may even stop microbial growth and kill susceptible organisms. However, it's important to note that bacterial growth can restart in thawed foods, so thawed foods should be treated like fresh perishables.