Beer is the oldest alcoholic drink and the one least often thought of as a cocktail ingredient, which is a mistake: the Michelada, the shandy, the Black and Tan and the boilermaker are all beer cocktails, and a cold lager is a better mixer than most sodas. The rules are simple. Light beers lengthen and lift; dark beers add weight and layer; bitter beers fight everything.

What is beer?

A fermented drink made from malted grain — barley above all, with wheat, rye, corn and rice in various styles — flavoured with hops and fermented with yeast. Ales ferment warm with top-fermenting yeast and are fruity and full; lagers ferment cold with bottom-fermenting yeast and are clean and crisp. Strength runs from 3% to over 10%, with most mixing beers at 4 to 5. For the bar the useful distinctions are colour (pale, amber, dark), bitterness (measured in IBUs, from a lager's 10 to an IPA's 60 and up), and carbonation, which is what beer brings to a drink that spirits cannot.

How it's made

Malted barley is milled and steeped in hot water to convert its starches to sugar; the sweet wort is boiled with hops for bitterness and aroma, cooled, and fermented with yeast for days or weeks. Lagers are then conditioned cold for weeks more. The beer is filtered or left hazy, carbonated naturally or by force, and packaged. Nitrogenated stouts — the kind with the creamy head — use nitrogen in place of some of the carbon dioxide, which gives small bubbles and a texture that matters for layered drinks.

What it tastes like

Pale lager: clean, light, faintly sweet, low bitterness — the mixer. Pilsner: crisper and more bitter. Wheat beer: soft, cloudy, banana and clove. Pale ale and IPA: hoppy, citrus, pine, bitter. Amber and brown ale: caramel and toast. Stout and porter: coffee, chocolate, roast. For cocktails, the first and last of those are what matter.

Styles worth knowing

Style	Character	In a drink
Mexican or light lager	Clean, crisp, mild	Michelada, Chelada, shandy, beer margarita
Pilsner	Crisp, more bitter	Shandy, Snakebite, boilermaker
Wheat beer	Soft, fruity	With fruit syrups; a Berliner-style shandy
Dry stout (nitro)	Roasty, creamy, low alcohol	Black and Tan, Black Velvet, a stout float on a flip
Pale ale / amber	Hoppy or malty, mid-weight	The base layer of a Black and Tan
IPA	Intensely bitter and aromatic	Rarely; a hop-forward beer cocktail if the bitterness is wanted

Which bottle to buy

A clean light lager for mixing and a nitro dry stout for layering. Those two cover nearly every beer cocktail. Buy cold, keep cold, and buy the freshest you can — beer is perishable and a stale lager makes a stale Michelada. Avoid IPA for mixing unless you want the bitterness.

Using it in drinks

Mexico has the best beer cocktails: the Chelada (lager, lime, salt) and the Michelada (lager, lime, hot sauce, Worcestershire and often tomato). Britain has the shandy (lager and lemonade) and the Snakebite (lager and cider). The Black and Tan layers stout over ale; the Black Velvet layers stout over Champagne. The boilermaker is a beer with a shot of whiskey beside or in it, and Korea's somaek is the same with soju. Beer also tops cocktails: a Beergarita is a Margarita lengthened with lager, and a stout float on a flip or a hot chocolate is a winter trick. Pour slowly, down the side, and never shake.

Substitutes

Hard cider for lager in a shandy or a Snakebite's other half; sparkling wine for lager in a Black Velvet's lighter layer; ginger beer or soda water where the beer is mainly there for fizz. Nothing substitutes for a stout's roast.

Storage

Cold, dark, upright, and fresh — most beer is best within months of packaging and declines in heat and light. An opened bottle is flat within hours; there is no keeping it. Buy what you will drink.

Questions

Can beer go in a cocktail shaker? No. Shaking carbonated beer foams it out of the tin. Build beer drinks in the glass and pour the beer last, gently.

Which beer for a Michelada? A light Mexican lager. The drink is about lime, salt and spice, and the beer is the cold, fizzy canvas.

What is a boilermaker? A shot of whiskey with a beer — sipped alongside, or dropped in. It is the original beer cocktail and needs no recipe.

Does beer have a place with spirits? As a chaser, as a layer, as a lengthener in a long drink, and as a float. The bitterness and carbonation do things no soda can.