ALE: One of two primary beer categories (the other being lager). Ale is the result when wort is fermented with so-called ale yeast (Saccharomyces cerevisiae). This type of yeast prefers relatively warm fermentation temperatures and works rapidly on the top of the fermenting vat. Largely due to the influence of the yeast, ales tend to be fruitier, spicier, and more aromatically complex than lagers.
CANDI SUGAR: Caramelized sugar that brewers sometimes use to boost the alcohol content of beer without adding body. Relying on malt sugar alone to achieve the desired alcohol would yield a heavier-bodied beer. The use of candi sugar—usually in liquid form—is common for many Belgian and Belgian-style ales, such as dubbels and tripels.
CRAFT BEER: The Brewers Association (BA) defines craft brewers as “small, independent, and traditional.” To the BA, small means an annual output of six million barrels of beer or less. Independent means that the brewery is not controlled by a larger, non-craft brewer. And, to simplify slightly, traditional indicates that the brewery’s flagship brew or the majority of its production is all-malt beer. In this context, malt means malted barley, and the intent is to exclude brewers who use cheaper grains like corn and rice to lighten flavor.
IBU: International Bitterness Units, the standard measure of bitterness in beer. IBU values are determined scientifically by measuring iso-alpha acids—the source of bitterness—in finished beer. In theory, IBU values range from 1 to about 100, although few beers measure below 8 or 10 and some extreme brews—such as some double IPAs and barley wines—can reach 120 IBUs.
LAGER: One of two primary beer categories (the other being ale). Lager is the result when wort is fermented with so-called lager yeast (Saccharomyces pastorianus). This type of yeast prefers relatively cool fermentation temperatures and works slowly on the bottom of the fermenting vat. Lagers tend to be crisper, simpler, and less diverse in flavor than ales. Another key difference: Lagers are lagered, or stored in cold conditions, for weeks or months before release to allow their flavor to mellow.
SESSION BEER: A brew of relatively low alcohol—typically, 5 percent alcohol or less—that won’t inebriate the person who consumes a pint or three over a long session at the pub among friends.
WORT: The sweet liquid that brewers ferment into beer. Wort is extracted from grains (primarily barley but also wheat, rye, and oats) by first sprouting the grains, then kilning (roasting) them, crushing them, and boiling them in water. The wort is the fermentable liquid drawn off of this mash.