American Sour

http://kitchenandbeerbar.com/wp-content/uploads/2018/05/american-sour-1.jpg

The acidity present in these beers is usually in the form of lactic, acetic and other organic acids naturally developed with acidified malt in the mash, or produced during fermentation by the use of various microorganisms. These beers may derive their sour flavor from pure cultured forms of souring agents or from the influence of barrel aging.