Learn how easy it is to make your own cultured buttermilk at home
Author: Jessica Fisher
In a quart size canning jar, combine the buttermilk and milk. Secure the cap.
Place the jar in a warm, dark place for 12-24 hours. I wrap mine in beach towels and place it above the refrigerator.
Refrigerate until ready to use.
I use whole milk because I like a thicker buttermilk.
I don't have to heat the milk when culturing buttermilk using the previous batch. I've tried it both ways and since overheating it once, realized it's a step that can be skipped. I simply add 1/2 cup buttermilk (I just eye-ball it actually) to the quart jar and fill the jar with regular milk.
Culturing 12 hours seems to do the trick. Any longer may cause some curdling. Overheating the milk can do the same. This curdling goes away with whisking, however, so it's not a big deal.
As long as the milk is thick and smells like buttermilk, you're good to go.
I have not tried this process with grocery store buttermilk, but my research says it works.
Reculture your buttermilk within 7 days for best results.
Recipe courtesy of Jessica Fisher, Good Cheap Eats