How can lower temperatures affect the growth of bacteria?

Refrigeration: Cold slows the metabolism of living things- which is why refrigeration works well in preserving food. If bacteria can't multiply as fast as at higher temps (close to 98 deg or a bit warmer) then food will not spoil as fast. Some bacteria, like Listeria, don't mind the cold but most do. Our own human metabolism slows down in the cold too-we even use this effect for severe heart attacks/brain injury