Phosphates are used in a variety of meat and poultry products for a number of reasons, including as processing aids and functional ingredients. The most common categories of products that use phosphates are cooked sausages, hams and other whole-muscle products where moisture retention is important. Phosphates are used in these types of products to increase the meat system pH to improve water-holding capacity, says Jeff Sindelar, associate professor in the department of animal science at the University of Wisconsin-Madison.
“The main functionality is to change the meat system pH, so that we are moving the pH of the meat further away from the isometric point,” he explains. “The isometric point of meat is around 5.2 to 5.3. By adding phosphates, we are adding additional charges to the meat system. Because of that, you are creating an imbalance between positive and negative charges, so you are changing basically the ionic strength in the meat system. You are causing the proteins to push away or swell, and because of that, you create more space for the protein charges that can grab onto water and bind water. This is also essentially the same mechanism of cooked sausages, which is where phosphates can help with protein extraction, and they do so by kind of the same type of mechanism.”