Are you one of those awful people who never have buttermilk in your fridge? STOP IT! Buttermilk is literally the most important ingredient in my refrigerator, I use it almost daily.
Flour sack towels: https://amzn.to/37Ry5fQ (I use these all the time in my kitchen for straining cheese or cold brew, or lining my rising bowls for sourdough bread.)
Grain/jelly bag: https://amzn.to/49GaLyU (Also superior to cheesecloth for straining, I also use it for infusing large batches of tea, making jelly, beer, etc.)
This video will explain how diverse buttermilk is for everything from baking to marinating, as well as the laughably simple method for making MORE buttermilk when you start to get low:
Refill your buttermilk container with any type of dairy milk (skim, 2%, whole, cow or goat), and you can use quality organic grass-fed milks to create a "premium" buttermilk that can be impossible to find in most area. Shake well to distribute the old buttermilk into the new milk, and leave on the countertop at room temperature until it thickens. (The cooler your kitchen, the longer it will take to ferment, from a minimum of a day, to potentially 3 or 4 days.) Once you can tell it has thickened, shake it and put it back in the fridge.
The more old buttermilk is in the container, the faster the milk will ferment. So if your container was empty, with only a little buttermilk clinging to the sides, it will also take longer for the new milk to ferment.
This method works best when you start with standard low-fat cultured buttermilk, rather than the "Bulgarian buttermilk" which uses a yogurt culture that prefers to ferment at temperatures warmer than room temp.
Both storebought and homemade buttermilk last FAR beyond the expiration date. It is only bad if mold is growing on the surface of the buttermilk, smells terrible, or it has separated into large, heavy clumps. (Some graininess or gentle separation is completely normal, just shake it to smooth it out. Buttermilk is, in fact, soured milk, so it should smell like sour milk...this doesn't mean it is BAD...technically it has already "gone bad" with an intentionally-selected strain of lactobacillus bacteria.)
If your buttermilk over-thickens, simply give it a good shake to loosen it up. If it's still too thick for your liking, add a little milk and shake it well, then put it back in the fridge.
To turn buttermilk into cheese, place in a covered, non-reactive, oven-safe pot and bake in the center of a 375F/190C oven for 20 minutes. Check for a clean separation between a fairly firm curd (the solid white part) and the greenish, clear liquid whey. If the separation isn't clear, bake an additional 5-10 minutes until the curd has fully separated. Strain through a flour sack towel ( https://amzn.to/37Ry5fQ ) or jelly/grain bag ( https://amzn.to/3hikPEf ), or cheesecloth or even an old, clean t-shirt, to separate the whey.
Refrigerate or freeze the whey, and use it in place of water, cup for cup or ounce for ounce, in ANY baking recipe, particularly bread and sourdough.
Hang the bag and allow the curds to drain for a minimum of 4 hours (for a creamy cheese), or up to 12 hours (for a drier, firmer, sharper cheese). Mix salt (at least 1 teaspoon of kosher salt, more to taste) and any desired additions into your cheese.
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Watch video Buttermilk 101: The MOST Important Ingredient that's not in your fridge right now online without registration, duration hours minute second in high quality. This video was added by user Ben Starr 26 December 2020, don't forget to share it with your friends and acquaintances, it has been viewed on our site 140,21 once and liked it 7.1 thousand people.