> [In cheese,] When the label says 'enzymes,' it is likely that they are using one of the new products; lots of people are having serious intestinal reactions to commercial cheeses. Real animal rennet is still safe, as far as I know. Industrial grade citric acid is a serious allergen for some people, because it contains contaminants that aren't in natural [[fruit]] citric acid, but it's probably safer than the industrial 'enzymes.' The producers of the enzyme products claim they are highly purified, but some people react as though they still contain some antigens from the microorganisms. The traditional cheeses were made with [[milk]] that soured with the bacteria that lived in the cows, but now it's common to sterilize the [[milk]], and then add cultures, or enzymes, or citric acid, for standardization---but they often put their faith in a commercial product that seems to work well, but that could have serious allergenic contaminants. The same thing has been happening with aged cheeses, many places are no longer letting the native molds infect the cheese curds. Homogenizing doesn't cause any problems---unless they use solvents/detergents for adding the vitamins A and D that are required in [[milk]] with reduced fat. The vitamins aren't normally added to whole [[milk]] or cream. > [TRYPTOPHAN CONTENT OF CHEESE] It varies a little with the method of making cheese, and the [[calcium]] content varies even more.  > The [[calcium]] content [of ricotta cheese] can vary greatly, depending on whether the whey is separated by acid or by bacterial proteolysis. > The ratio of [[calcium]] to phosphate is more important than the absolute amount of [[calcium]]. 4 ounces [Parmegioanno Regiano] would usually be enough.