Milk (left) compared to buttermilk (right). Buttermilk is thicker and leaves a more visible residue on the glass.
Serving temperatureChilled
Main ingredientsMilk
Food energy
(per serving)
40 (100 grams) kcal
Nutritional value per 100 g (3.5 oz)
Energy169 kJ (40 kcal)
4.8 g
0.9 g
3.3 g
116 mg
Percentages are roughly approximated using US recommendations for adults.

Buttermilk is a fermented dairy drink. Traditionally, it was the liquid left behind after churning butter out of cultured cream. As most modern butter in western countries is not made with cultured cream but uncultured sweet cream, most modern buttermilk in western countries is cultured separately. It is common in warm climates where unrefrigerated milk sours quickly.[1]

Buttermilk can be drunk straight, and it can also be used in cooking. In making soda bread, the acid in buttermilk reacts with the raising agent, sodium bicarbonate, to produce carbon dioxide which acts as the leavening agent. Buttermilk is also used in marination, especially of chicken and pork.

Traditional buttermilk

Originally, buttermilk referred to the liquid left over from churning butter from cultured or fermented cream. Traditionally, before the advent of homogenization, the milk was left to sit for a period of time to allow the cream and milk to separate. During this time, naturally occurring lactic acid-producing bacteria in the milk fermented it. This facilitates the butter churning process, since fat from cream with a lower pH coalesces more readily than that of fresh cream. The acidic environment also helps prevent potentially harmful microorganisms from growing, increasing shelf life.[2]

Traditional buttermilk is still common in many Arabic, Indian, Nepalese, Pakistani, Finnish, Polish, and Dutch households, but rarely found in other Western countries. It is a common drink in many Indian and Nepalese homes, and often served with roasted maize.[3] In the Arab world, buttermilk is a common beverage to be sold ice cold with other dairy products. It is popular during Ramadan, where it is consumed during iftar and suhur.

Cultured buttermilk

United States

Cultured buttermilk was first commercially introduced in the United States in the 1920s. Commercially available cultured buttermilk is milk that has been pasteurized and homogenized, and then inoculated with a culture of Lactococcus lactis or Lactobacillus bulgaricus plus Leuconostoc citrovorum to simulate the naturally occurring bacteria in the old-fashioned product.[3] The tartness of cultured buttermilk is primarily due to lactic acid produced by lactic acid bacteria while fermenting lactose, the primary sugar in milk. As the bacteria produce lactic acid, the pH of the milk decreases and casein, the primary milk protein, precipitates, causing the curdling or clabbering of milk. This process makes buttermilk thicker than plain milk. While both traditional and cultured buttermilk contain lactic acid, traditional buttermilk tends to be less viscous than cultured buttermilk.[3]

When introduced in America, cultured buttermilk was popular among immigrants, and was viewed as a food that could slow aging. It reached peak annual sales of 517,000,000 kg (1.14 billion lbs.) in 1960. Buttermilk's popularity has declined since then, despite an increasing population, and annual sales in 2012 reached less than half that number.[4]

However, condensed buttermilk and dried buttermilk remain important in the food industry.[5] Liquid buttermilk is used primarily in the commercial preparation of baked goods and cheese.[6] Buttermilk solids are used in ice cream manufacturing,[7] as well as being added to pancake mixes to make buttermilk pancakes.

Acidified buttermilk

Acidified buttermilk is a substitute made by adding a food-grade acid such as white vinegar or lemon juice to milk.[8] It can be produced by mixing 1 tablespoon (0.5 US fluid ounces, 15 ml) of acid with 1 cup (8 US fluid ounces, 240 ml) of milk and letting it sit until it curdles after about 10 minutes. Any level of fat content for the milk ingredient may be used, but whole milk is usually used for baking.


Commercially produced buttermilk is comparable to regular milk in terms of food energy and fat. One cup (237 mL) of whole milk contains 660 kilojoules (157 kilocalories) and 8.9 grams of fat. One cup of whole buttermilk contains 640 kJ (152 kcal) and 8.1 grams of total fat. Low-fat buttermilk is also available.[9] Buttermilk contains vitamins, potassium, calcium, and traces of phosphorus.[10]

See also


  1. ^ Muhlke, Christine (April 22, 2009). "Got Buttermilk?". New York Times.
  2. ^ Douma (Ed.), Michael (June 14, 2007). "Ripening to Ferment Milk Sugars to Lactic Acid". Webexhibits. Retrieved 2008-12-31.
  3. ^ a b c Fankhause, David B. (June 14, 2007). "Making Buttermilk". University of Cincinnati Clermont College. Archived from the original on August 28, 2007. Retrieved August 21, 2007.
  4. ^ Anderson, L.V. (2012). "All Churned Around: How buttermilk lost its butter". Slate. Retrieved March 3, 2017.
  5. ^ Hunziker, O F (January 1, 1923). "Utilization of Buttermilk in the form of Condensed and Dried Buttermilk" (PDF). Journal of Dairy Science. American Dairy Science Association. 6 (1): 1–12. doi:10.3168/jds.S0022-0302(23)94057-9. Retrieved 2010-10-26.
  6. ^ Sodini, I.; Morin, P.; Olabi, A.; Jiménez-Flores, R. (February 2006). "Compositional and Functional Properties of Buttermilk: A Comparison Between Sweet, Sour, and Whey Buttermilk" (PDF). Journal of Dairy Science. American Dairy Science Association. 89 (2): 525–536. doi:10.3168/jds.s0022-0302(06)72115-4. PMID 16428621. Retrieved March 16, 2019.
  7. ^ "Dry buttermilk and nonfat dry milk price relationship". U.S. Dept. of Agriculture. Economic Research Service. August 1991. Archived from the original on 2008-12-04. Retrieved 2008-06-28.
  8. ^ "Title 21 – Food and Drugs: Chapter I, Part 131 Milk and Cream" (PDF). Electronic Code of Federal Regulations (e-CFR). April 1, 2007. Retrieved 2010-10-26.
  9. ^ Filippone, Peggy Trowbridge. "Buttermilk health benefits". Archived from the original on July 26, 2016. Retrieved October 13, 2013.
  10. ^ Aparna, Karthikeyan (May 13, 2012). "Buttermilk, the best bet". The Hindu. Chennai, India. Retrieved October 13, 2013.