Stock Ale is one of three related traditional British strong, fruity ale styles, the others being old ale and barley wine. Mention of stock ale begins to appear in brewing books of the late 1700s. The definitions of these categories, however, have never been very precise, either technically or historically. More likely than not stock ales were generally strong, because they were made only from the first, high-gravity runnings of a parti-gyle brew. They also usually needed several months to even a year to mature in casks. This mellowed their heavy, sometimes cloying flavors and made them palatable. Over time, stock ales would oxidize in storage, taking on lactic and musty notes from lactobacillus and brettanomyces organisms in the casks. At one time this acidity, so long as the flavor had not become vinegarlike, was considered desirable. See brettanomyces, lactobacillus, old ales, original gravity, oxidation, and parti-gyle.

Beers called stock ales, although malt accented, were generally more strongly hopped than old ales and had at least 7.5% alcohol by volume (ABV) but often closer to 9% ABV. Much of the strength came from wort, but some recipes called for up to 25% added sugar in the kettle. The preservative effects of plenty of alcohol and hop bitterness are probably responsible for the brew’s name of “stock” ale; it was certainly beer for keeping as opposed to a “running beer” meant to be served soon after fermentation. Publicans who were willing to blend individual pints for customers, including the fabled “three-threads,” may well have added stock ale for extra complexity. See three-threads. A less kind contemporary interpretation of the three-thread pour, however, was that it was a way for publicans to get rid of unpalatable, oxidized cask residues. Barley wine, the third classic British strong ale, was a much later development than stock and old ale. Developed as a house beer for the British aristocracy, barley wine only reached the commercial marketplace at the end of the 19th century. In fact, the first beer marketed as barley wine was released as late as 1903, by Bass, under the brand name of “Bass #1.” It, too, was a first-runnings beer. Modern American craft brewed examples of stock ales seem to be less massive than their traditional British forbears, and they generally have no lactic character. These beers, although perhaps slightly stronger than regular pale ales, tend not to reach the alcoholic heights of the British classics, but they may exceed them in hopping rates, both for bittering and for aroma. Most are fairly pale, and this may be traditional, because recipes from around 1900 call for only pale malt.