Now m'dears, you know I am prone to visions, feelings, and predictions as to the future. And I think hard times may be coming. Very hard times. And in those hard times, there will be the wealthy, as there always are, and there will be the down-and-outs, in numbers greater than usual. And you can guess which group I will be in.
In olden days, people were not nearly as picky about their food. Food was often not in plenty. And that gave a delicious appreciation for anything edible. My father ate fried squirrel with relish (and relish), though he felt terrible for the squirrels he killed. But it was the squirrels or his little brothers and sisters. They had to have something. And while a few of ye rascals may attempt to claim buttermilk is not edible -- or rather, potable -- I'm here to tell you to know how to make it and drink it.
There may come a day when you need an easily obtained, easily digested food source. Buttermilk is pre-digested -- doesn't that sound appetizing? The lactose has been turned into lactic acid - the stuff that makes your muscles ache terribly when working out! Little critters eat up the lactose and, um, well, "create" the lactic acid! Isn't this just getting better and better? Please hold your nausea until the post is finished!
Like sourdough bread, making buttermilk requires a "starter" of -- buttermilk! Buy a pint if they have it and a quart otherwise. Buy powdered skim milk, too. Make up some of the powered milk. I'm going to assume you are wanting to make a half-quart of buttermilk, so have two pint jars on hand, washed and sterile. Pour the store-boughten buttermilk into each pint jar to the halfway mark (doesn't need to be exact). Now, add in a pinch of salt. Top off each jar with some of the skim milk you have made. Cover the jars with layers of clean cheesecloth topped with a clean kitchen towel, or use bleached flour sacks, freshly bleached and dried. Let the jars set out overnight. They will "clabber." And you will have 2 glasses of buttermilk per pint. Pour off the buttermilk and DRINK IT. Or use it in cooking. Or both.
Put the empty pint jars in the fridge. Don't wash them! At night, take them out the fridge. Now take more of the skim milk powdered mix and mix it up and fill up the jars again, this time you don't have to add in any store-boughten buttermilk. I leave a bit of the first buttermilk in mine. Let sit overnight again, and in the morning -- more buttermilk to pour off and drink!
Continue making buttermilk this way until the health department shows up! No no, do so for a few weeks, then wash the jars and begin again.