Pork and beans
Pork and beans is a culinary dish that uses beans and pork as its main ingredients. It is routinely purchased canned and reheated on a stove or in a microwave oven. Numerous variations exist from Fabada Asturiana to Olla podrida to American canned pork and beans. Although the time and place of the dish's invention is unclear, it was well established in the American diet by the mid-19th century. The 1832 cookbook The American Frugal Housewife lists only three ingredients for this dish: a quart of beans, a pound of salt pork, and pepper. According to the 1975 Better Homes and Garden Heritage Cookbook, canned pork and beans was the first convenience food.
American canned pork and beans 
Commercially canned pork and beans were introduced in the United States during the 1880s. The dish is "an American canned classic, [and] is recognized by American consumers generally as an article of commerce that contains very little pork." This is due to the high fat content of the salt pork traditionally used for the last 180 years in American pork and beans, which often renders into solution when sufficiently heated.
The recipe for American commercially canned pork and beans varies slightly from company to company, but generally consists of rehydrated navy beans packed in tomato sauce (usually made from concentrate and which may incorporate starch, sugar, salt and seasoning) with small chunks of salted pork or rendered pork fat. The ingredients are cooked and packed into hermetically sealed containers and processed by heat to assure preservation.
See also 
- Food and wine Asturian Pork and Beans Recipe
- Caterersearch article Full of beans
- The American Frugal Housewife pg 51 - Project Gutenberg free ebook
- New York Times article That's What and Beans? Pork Defends Its Image published April 1, 1998
- Siddiq, Muhammad, Masood S. Butt, and M. Taurus Sultan. "Dry beans: Production, Processing, and Nutrition" in Handbook of Vegetables and Vegetable Processing, Sinha, Nirmal K., et al, eds. (2010) Wiley & Sons, pp. 545-64; p. 556. ISBN 978-0-8138-1541-1.
- "United States Standards for Grades of Canned Pork and Beans" in United States Standards for Grades of Canned Dried Beans (2006) Agricultural Marketing Service, USDA, p. 12.