Asked by: Jacob Hipkiss, Southwell

As cells die, their membranes degrade and enzymes start leaking out. The cell digests itself, then neighbouring cells, and the process cascades. Without any immune response to stop them, bacteria and fungi will also begin eating the food and multiplying. As they munch away, they alter the texture of the food and release waste products that change the taste. There are purely chemical rotting mechanisms too, like fat oxidation, which makes it taste rancid.

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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.