I make my own strach. I boil two cups of water add two tablespoons of cornstarch and one tablespoon of borax. The borax is a preservative that keeps the starch fresh for weeks. Had to experiemnt with the water to concentrate ratio but have it fine tuned now. I add 1 cup of water to one half cup of starch shake well and test it, adding more starch or water as needed. I keep a jar of the boiled starch in the fridge and it keeps a long time.