Slowing Food Spoilage

Slowing Food Spoilage

Food spoils when microbes, such as moulds and bacteria, grow in it. Natural substances called enzymes can also change its colour, taste and texture. Preservation methods slow spoilage by making conditions less suitable for microbes or by slowing enzyme action.

A fridge keeps food cool, so microbes grow more slowly. Freezing stops most growth while food stays frozen, but it does not kill every microbe. Once thawed, food must be stored and used as instructed.

Drying removes much of the water that microbes need. Salt or sugar can also make water less available, but only when enough is used in a tested recipe. Pasteurisation uses controlled heating to kill many microbes; some products still need refrigeration. Safe canning depends on the right heat process, food acidity, sealed packaging and storage instructions, not simply putting hot food into a clean jar.