Baking Tip: How to Make your own Buttermilk
I have a newest favourite ingredient. Buttermilk. Who would have imagined that buttermilk would hold that honoured position? Not only is it my current fad, but learning how to make my own buttermilk has felt liberating. I no longer feel like there's a barrier stopping me from baking a recipe because buttermilk is 'another ingredient that I don't have' or 'where can I buy that from?' when I come across it in a list of ingredients. Since discovering how to make my own cultured buttermilk, my oven has been turning out soda bread, raspberry and buttermilk cake and vast quantities of Allinson's Banana Cake.
I first came across it when baking scones for an international tea party for 300 students. A friend of mine recommended Delia's buttermilk scone recipe to me and every single batch turned out great. They rose perfectly and were springy in the middle. Then, I made the banana cake that was on the back of the self-raising flour packet with the leftover buttermilk. Wow - that turned out to be a winner too.
Buttermilk is the liquid that is leftover from the butter making process. Cultured buttermilk that is commonly sold in supermarkets today is curdled, sour milk. I know... I'm really selling it to you, aren't I? Appetising, it does not sound. However, it is a lovely ingredient when you use it in baking because you're pretty much guaranteed lightness and a good rise. When I researched the chemistry, I was told that the acid in the buttermilk reacts with the sodium bicarbonate to release carbon dioxide. Those large bubbles help the mixture to rise quickly. Oh, and means you can bake soda bread within an hour from start to finish.
There are two ways that you can make it:
1. Shake double cream really, really hard for a long time and not only will you have butter (and a new muscle-toning exercise) but you'll have buttermilk from the leftover liquid, or
2. Add 1 tbsp/15ml of white or cider vinegar or lemon juice to 225ml/8fl oz of milk (preferably whole, or at least semi-skimmed) and wait about 10-15 minutes for it to curdle. This is the much easier way. Essentially, buttermilk is curdled, sour milk. I prefer to use lemon juice because the smell is that wee bit more safer when baking a sweet cake, but it doesn't matter really.
I experimented, as you'd expect me to, with whether the fat content of the milk makes a difference. I think it does. Full-fat milk will curdle better. My results with skimmed milk were disappointingly watery. Those of you who are lactose intolerant or vegan will be pleased to read that you can make it with unsweetened soya milk too. It just needs a bit more vinegar/lemon juice.
I'm still chuckling to myself, as I write this, because it is a random ingredient to get excited about. Oh, I should also add that Miss Buttermilk comes as a pair with Mr. Bicarbonate of Soda.