Some weeks ago I posted a link to a video of the BBC program “Bang goes the theory” which explained why cream whips. In passing, it also showed how butter is done. It looked so easy that I decided to give it a try myself and it was indeed as easy as it looked!
By the way, “Bang goes the theory” is back again on Wednesdays at 19.30 on BBC One.
Back to our butter. All you need is some double cream and a mixer. Actually, in another BBC program “Jimmy’s Food Factory” he did it without a mixer, by just shaking the cream in a jar. But if you appreciate your wrists, I do not recommend this :S.
We start with the double cream in a tall glass to avoid spilling. Cream is an emulsion of water and fat. Normally, as we know, water and fat don’t mix. They need the help of an emulsifier to do it. This is a molecule that gets attached to water on one hand and to fat on the other, helping them mix together. It has to be double cream because single cream does not have enough fat to be whipped.
We start whipping, ideally with a mixer and after a few seconds we see it rising and making a thick foam. What we are doing is inserting air bubbles into the mix. The fat molecules wrap these bubbles protecting them and keeping them from bursting.
What happens if we keep mixing after this is that we start breaking the air bubbles. When one of them collapses, all the fat molecules around it come together making a big lump. All these lumps start coming together and the water is left out: we have reversed the emulsion! What we have now is a lump of butter floating in some white liquid called butter milk.
Then just strain all the liquid out and you have made your own butter!
You can just enjoy it as it is on your bread, with some salt or you could even flavour it with your favorite ingredients: herbs, chillies, salmon, lemon and dill, you name it!