I hate buying a full quart of buttermilk because of a recipe calling for a cup. So, I tried a recipe for making buttermilk at home. Every recipe I find calls for adding white vinegar or even lemon juice to "milk". I tried this using my normal nonfat milk we use at home and was not real impressed with results. By "milk", does one mean whole, 1%, 2% or what??@@#$%