Question: why do some foods rot quicker than others

Matthew Lee answered on 22 Jun 2017:

Hmmm thats a good question, not entirely sure. Theres lots of different reasons why foods rot, from heat, light, humidity, bacteria around them, bacteria in them. But one reason is to do with water, and how much water is in a food and what state the water is in. Water can either be free or bound inside food. Free means its floating around in the food and can be used by microorganisms to grow, think of a tomato. While bound means the water is attached to molecules inside the food and so cant be used by microorganisms. So if the food has lots of free water then the microorganisms can grow much better if they get inside the food, this is why lots of food have shells or barriers, like the skin of a tomato. So you have to take into account loads of different factors when thinking why some foods rot faster than others.