Hops

Hops make beer bitter, stable, and aromatic, and in a Welsh bitter they do so with a light touch. Britain's major hop-growing regions lie in England, in Kent, Herefordshire, and Worcestershire. From there come the classic varieties Fuggle and Goldings, earthy, spicy, and lightly floral in character.

So how bitter is a bitter, really? By the BJCP style guidelines, a best bitter sits at 25 to 40 IBU. The unit measures bitterness in milligrams of iso-alpha acid per liter. A dark mild comes in noticeably lower, at 10 to 25 IBU, while an English IPA reaches 40 to 60. The name "bitter" is really more a comparison to the sweeter mild than a literal promise.

Brewers distinguish between bittering hops and aroma hops. Bittering hops are boiled for a long time in the wort, so their alpha acids deliver the sharpness. Aroma hops go into the kettle late, or are even added cold directly to the cask, so their fragrance doesn't boil off. Traditional Welsh beers tend to lean on the former.

The new wave of Welsh breweries has switched things up. Tiny Rebel in Newport names one of its beers Clwb Tropicana, a nod to the fruity American-style aroma hops it uses: Cascade, Citra, Mosaic. These hops grow in the Yakima Valley and other regions, traveling to Wales as pellets. So anyone trying a beer from South Wales quickly gets a sense of whether it belongs to the old school or the new. The difference shows up on the nose: earthy and hay-like, or bright and bursting with mango.