Processed cheese

Processed cheese (also known as prepared cheese, cheese product, plastic cheese, or cheese singles) is a food product made from cheese (and sometimes other, unfermented, dairy by-product ingredients), plus emulsifiers, saturated vegetable oils, extra salt, food colorings, whey or sugar. As a result, many flavors, colors, and textures of processed cheese exist. Its invention is credited to Walter Gerber of Thun, Switzerland, in 1911.

Processed cheese has several technical advantages over natural cheese, including a far longer shelf-life, resistance to separating when cooked, and a uniform look and physical behavior. Its mass-produced nature provides arguably its greatest advantage over natural cheese: a dramatically lower cost — to producers and consumers alike — than conventional cheesemaking. This, in turn, enables industrial-scale production volumes, lower distribution costs, a steadier supply, and much faster production time compared to traditional cheeses.

The use of emulsifiers in processed cheese results in a product that melts without separating when cooked; with prolonged heating, some natural cheeses (especially cheddar and mozzarella) separate into a lumpy, molten protein gel and liquid fat combination. The emulsifiers (typically sodium phosphate, potassium phosphate, tartrate, or citrate) reduce the tendency for tiny fat globules in the cheese to coalesce and pool on the surface.

Because processed cheese does not separate when melted, it is used as an ingredient in a variety of dishes. Unlike some unprocessed cheeses, heating does not alter its taste or texture.

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Wikipedia