Phosphonate salts are the result of deprotonation of phosphonic acids, which are diprotic acids: Phosphonate esters are the result of condensation of phosphonic acids with alcohols. Several methods exist for the preparation of phosphonic acids and their salts.
1 Stir in the tomato sauce, tomato paste, vinegar, diced tomatoes, and brown sugar. Season with chili powder, Italian seasoning, and salt. Bring to a boil, reduce heat to low, and simmer 1 hour.  Mix the cornstarch and water, and stir into the salsa to thicken. Transfer salsa to sterilized jars, leaving 1/2 inch headroom, and seal. Process jars in a boiling water bath 15 minutes. Store unsealed jars in the refrigerator.
1 Add sliced onions to a medium bowl. 2  Pour enough boiling water over onions so that they are covered. 3  Count to 10 then drain. 4  Add onions to glass jars or a bowl. 5  Toast cinnamon, cloves and the red pepper flakes in a small saucepan over medium heat until fragrant, 3 to 5 minutes.