North/Central Europe: Buttermilk Plant
It can sometimes be extremely frustrating to try to do Irish cooking -- which invokes buttermilk constantly -- when you're in a place where they've never heard of buttermilk, or just can't get it.
Even in Ireland this problem used to pop up in the old days before cheap refrigerated transport, during the winter, when the cows weren't giving milk. However, the Irish (like various other dairying people around Europe) found a way around this problem. It has gone by many names over the years: one of the commonest was "bull's milk". And the way you made bull's milk was by making, and keeping, a buttermilk plant.
This is a yeast-based starter similar to the one that keeps the famous "Herman" baking starter going. It takes a certain amount of care to keep going. But it produces a product which is close enough to buttermilk for cooking and baking purposes. (Some people do drink it: your mileage, as they say, may vary.)
The ingredients of the plant are simple: yeast, sugar and skim milk. Most people who've made this agree that it's best to start with fresh yeast if you can get it.
First of all, find a glass container slightly larger than a quart. Wash it, let it drain dry, and then scald it out twice with boiling water and let it drain dry again. The cleanliness factor is very important for this preparation. The friendly yeasts and lactic bacteria that make up the culture of the buttermilk plant are pretty robust, but you have to help them out by making sure that no "rogue" bacteria or yeasts make their way into the process.
Then: If you can get it, cream a one-ounce cube of yeast together with one ounce of sugar. (If you can't get fresh yeast, dissolve an ounce of dried yeast together with about a teaspoon of water, just enough to make a paste: mix it up and then add the sugar and cream them together.)
Then mix together --
- 1 pint warm water
- 1 pint skim milk
Make very sure that the final mixture is merely tepid. Water that is too hot will kill the yeast and leave you with a nasty smelling mess after a few days, not the buttermilk substitute you're looking for.
Gradually add the tepid milk-and-water mixture to the yeast and sugar. Then pour the whole business into the scalded container, cover it, and leave it in a warm place (75-80F) for a couple of days. It will slowly start to smell like buttermilk.
When you're ready to use the substitute buttermilk from the plant, put a linen or cotton dishtowel into the bottom of a strainer, and strain the contents of the scalded container through it. Once you've finished straining, you will find an odd-looking lumpy residue in the strainer. This is the "buttermilk plant" proper: it's the seed of your next batch.
Having put aside the strained-off "buttermilk", you now have to start the next batch. To do this, you need to wash and again scald (twice!) the container you were using. While it's draining, you then carefully rinse the granules of the buttermilk plant with a couple / few cups of tepid water (remember, not too hot, the yeast is very sensitive...) until all the milk has been rinsed away. Scrape the rinsed plant off the dishtowel into the scalded (and cooled) container. Add another quart of tepid milk and water, cover again, and leave to increase and multiply. (It will increase over time, and you can give spoonfuls of it to friends if they're interested.)
There are just a few other rules for keeping this process going:
- You must strain the plant / milk / water at least every five days, rinse the "plant", and remake it. Otherwise it will go bad. If you have to go away somewhere and don't want to just abandon the plant and start a new one when you get home, give it to a friend with these directions and ask them to take care of it for you until you get back. (As with sourdough starter, there is some evidence that the longer you can keep one of these going, the better it gets.
- Make sure the milk-and-water is never more than lukewarm.
- Continual cleanliness is extremely important. Don't be tempted to pass on the double scalding of your container.