Jimmy opens the fridge door to see what is done to make even nature's simplest foods safe for us to eat. He starts with milk. Every day in the UK 36 million litres are produced, but before it arrives on the supermarket shelf it is pasteurised and homogenised - but what does that involve? He also attempts to make his own reduced fat spread to find out what they do to vegetable oil to make it spreadable.Jimmy copies the modern dairy processes by assembling his own production line using a high pressure washer, a tin bath, a fire extinguisher, a car jack, fence posts, a stepladder and a collection of buckets.He is also surprised to unearth some of the imperfect wrinkly eggs that never make it onto the supermarket shelves and discovers how bacteria are used to turn milk into Red Leicester cheese.