Everything I’ve seen online corresponds with Fondots’ explanation. I found this FDA regulation that (if I’m reading/skimming it right) pretty much stipulates that “American Cheese” is a “pasteurized process” cheese, which means (among other things) it includes emulsifiers. It also points out that “American Cheese” is made by processing other cheeses, which may include Swiss, but Swiss is just one of many options.
Everything I’ve seen online corresponds with Fondots’ explanation. I found this FDA regulation that (if I’m reading/skimming it right) pretty much stipulates that “American Cheese” is a “pasteurized process” cheese, which means (among other things) it includes emulsifiers. It also points out that “American Cheese” is made by processing other cheeses, which may include Swiss, but Swiss is just one of many options.