Velveeta

Ingredients: Natural cheese (American (cheddar and colby(milk, cheese culture, salt, enzymes))), water, whey, whey protein concentrate, sodium phosphate, skim milk, milkfat,salt, sorbic acid, apocarotenal, annatto.

What is the function of sodium phosphate?

This has 6g of fat per serving. How could you make it reduced fat? Lowfat? Nofat?