American cheese is a processed cheese. It is orange, yellow, or white in color and mild in flavor, with a medium-firm consistency, and melts easily. American cheese was originally only white, but is sometimes now modified to yellow. In the past, it was made from a blend of cheeses, most often Colby and Cheddar. Today’s American cheese is generally no longer made from blended cheeses, but instead is manufactured from a set of ingredients such as milk, whey, milkfat, milk protein concentrate, whey protein concentrate, and salt. In the United States, it may not be legally sold as "cheese", and must be labeled as "processed cheese", "cheese product", or similar—e.g., "cheese food". At times even the word "cheese" is missing in the name on the label, e.g. "American slices" or "American singles". In Canada, exactly the same product, often by the same manufacturer with the same label design, used to be sold as "Canadian cheese" or "Canadian slices". Today, most such product in Canada is vaguely labelled just "slices" or "singles". In the United Kingdom, packs are labelled as "singles", although it is commonly called cheese slices.
The marketing label "American cheese" for processed cheese combined with the prevalence of processed cheese in the U.S. compared to the rest of the world has led to the term American cheese being used in the U.S. synonymously in place of processed cheese. The term "American cheese" has a legal definition as a type of pasteurized processed cheese under the U.S. Code of Federal Regulations.
British colonists made cheddar soon upon their arrival in America. By 1790, American cheddars were being exported back to England. The British referred to American cheddar as "American cheese", or "Yankee cheese", and post-Revolution Americans promoted this usage to distinguish their product from European cheese. For example, an 1878 newspaper article in The New York Times lists the total export of American cheese at 355 million pounds per year, with an expected growth to 1,420 million pounds.
After the invention of processed cheese in 1911, and its popularization by James L. Kraft in the late 1910s and 1920s, the term "American cheese" rapidly began to refer to this variety rather than to American cheddar. The latter had already begun to be produced on an industrial scale in the 1890s, leading to the term "factory cheese". And in the 1920s another slang term arose for the still-popular cheese: "rattrap cheese", or "rat cheese".
The Oxford English Dictionary defines American cheese as a "cheese of cheddar type, made in the U.S." and lists 1804 as the first known usage of "American cheese", occurring in the Frankfort, Kentucky newspaper Guardian of Freedom. The next usage given is in 1860 by Charles Dickens in his series The Noncommercial Traversal.
1942 U.S. restriction to American cheese 
During the summer months of 1942, U.S. officials imposed severe restrictions on cheese consumption as a wartime conservation measure. These restrictions disallowed the sale or consumption of all types of cheese other than American cheese. This was due to a combination of factors: paucity of availability of cheese from continental Europe, abundance of the American variety, and a perceived need to encourage wartime patriotism among citizens. The ban took effect on May 4, 1942.
The public response to the ban was immediate and noticeable. Importers of British cheese claimed that it damaged morale in both countries, and represented a lack of solidarity in the war effort on the part of the USA. For these reasons and others, the ban was rescinded without opposition on August 1, 1942.
Modern varieties 
Even though the term “American cheese” has a legal definition in the United States as a type of pasteurized processed cheese, products called "American cheese" are by no means identical. Depending on the additives and the amounts of milk fat and water added to the cheese during emulsification, the taste and texture of American cheese varies, with some varieties (e.g. "American cheese" and "American processed cheese") being very similar to non-processed cheese and other varieties (e.g. "American cheese food" and "American cheese product") being more like Velveeta or Cheez Whiz. The interested consumer should pay close attention to the wording used on the label of each product and to the ingredient list. (Refer to the definitions in the Sale and labeling section of the article on Processed cheese.)
The taste and texture of different varieties of American cheese vary considerably, and mostly depend on the percentage of cheese versus additives used during emulsification. Varieties with lower percentages of additives tend to taste more like unprocessed cheese. Depending on the food manufacturer, the color of the cheese (orange, yellow, or white) may indicate different ingredients or processes. Some manufacturers reserve the white and yellow colors for their less processed (i.e. fewer additives) American cheese varieties. In other cases, the ingredients for white and orange colors are the same, except for the coloring. However, this does not necessarily mean that even these white and orange cheeses have exactly the same flavor and texture because the spice annatto, which has a subtle but noticeable taste, is often used for coloring American cheese.
The processed variety of American cheese is sold in three basic packaging varieties: individually wrapped cheese slices (which technically are not slices, sliced off a block of cheese, but rather slabs of processed cheese which are formed from a viscous processed cheese which only solidifies between the wrapping medium), small pre-sliced blocks of 8 to 36 slices, and large blocks meant for deli counters. The individually wrapped cheese slices are typically the least like unprocessed cheese. Small (e.g., 8- to 36-slice) blocks of pre-sliced, but not individually wrapped American cheese are also marketed, often with the branding "deluxe" or "old-fashioned". This variety of American cheese is similar in ingredients and texture to that of modern block American cheese. Before the advent of the individually wrapped variety, this was the typical variety that Americans purchased. Hence, some people refer to this as "classic" or "traditional" American cheese.
See also 
- Kraft Singles (Orange) Ingredients List.
- "Standards of Identity for Dairy Products". MilkFacts.info. Retrieved 2013-02-25.
- "Tesco Everyday Value Singles 255G - Groceries - Tesco Groceries". Tesco.com. Retrieved 2013-02-25.
- Under the U.S. Code of Federal Regulations Title 21 (Food and Drugs), Article 133, Section 169 (Pasteurized processed cheese), the allowed usage of the term "American cheese" for certain types of "Pasteurized processed cheese" is detailed. Specifically, in paragraph (e)(2)(ii) of section 133.169, it states In case it is made of cheddar cheese, washed curd cheese, colby cheese, or granular cheese or any mixture of two or more of these, it may be designated "Pasteurized processed American cheese"; or when cheddar cheese, washed curd cheese, colby cheese, granular cheese, or any mixture of two or more of these is combined with other varieties of cheese in the cheese ingredient, any of such cheeses or such mixture may be designated as "American cheese."U.S. Food and Drug Administration (April 1, 1999). "Title 21, Article 133". U.S. Government Printing Office. Retrieved 2007-02-17.
- Robert Carlton Brown, The Complete Book of Cheese (New York: Programer Publishing Company, 1955). Republised in 2006: "Bob" Brown, The Complete Book of Cheese (Echo Library, 2006).
- "The Cheese All Inspected", The New York Times, December 8, 1878: 5
- Stuart Berg Flexing, Listening to American: An Illustrated History of Words and Phrases from Our Lively and Splendid Past (NY: Simon and Schumpeter, 1982).
- Edited by Edmund Whiner and John Simpson. (1991), Oxford English Dictionary I (Second ed.), Oxford, UK: Oxford University Press, p. 397, ISBN 0-19-861258-3
- Wallenstein, Harvey (2003). Paradox of Plenty: A Social History of Eating in Modern America. University of California Press, p. 82.
- Spinnaker, Awe: Brown Bread for Victory: German and British Wholemeal Politics in the Inter-War Period, in: Treatment, Frank and Just, Flemming (ed.): Food and Conflict in Europe in the Age of the Two World Wars. Basing stoke / New York: Palaver, 2006, pp. 143-171, ISBN 1-4039-8684-3
- Making American cheese on the farm for home consumption, Farmers' Bulletin No. 1734, U.S. Department of Agriculture, October 1934. Hosted at University of North Texas Government Documents Department.
- An American-type cheese: how to make it for home use, Farmers' Bulletin No. 2075, U.S. Department of Agriculture, October 1954.