Thanks, Rosen. I've used both, and also the powdered kind. They're fine for baked goods, but I like the real thing for fried chicken and salad dressings. My grandma used to buy the real thing from the farm, so I know what it's supposed to taste like. The cultured buttermilk at the supermarket comes close to farm buttermilk, and it's naturally low fat. It comes in quart containers so you don't have a lot of waste. It is so good to marinate chicken and pork in.
I wouldn't buy a whole quart of buttermilk to get a cup worth for a cake. I am not that much of a food snob. For the chicken recipe, I'd get the buttermilk. I think the soured milk would curdle in the oven, and you'd wonder why everyone was raving over the recipe when it tasted so bad to you. The powdered stuff can be pretty good, but be careful it can go rancid.
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