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How to Make a Sourdough Starter. Much better results than water and flour from original recipes. The pineapple juice prevents a harmful batteries from growing that affects about 40% of sourdough starters. The smell and taste of this one in sourdough breads is much more preferred IMO.
How To Make A Sourdough Bread Starter with Just Flour and Water - this is a GREAT post with good info!
Yeast - Recipes call for different types. Make sure you have the right one or know how to substitute!