Ale and lager

The whole of beer divides in two, and the dividing line is which yeast and how cold. Everything else - colour, strength, hop character - cuts across both.

Warm yeast is more active: it throws off esters and phenols, which land as banana, pear, clove and pepper. Cold yeast works slowly and quietly and leaves very little of itself behind. That's why a lager tastes clean and a Belgian ale tastes of fruit nobody added.

Lager is German for "to store", which is the technique rather than a description of the beer. Lagering is cold conditioning, and it's the reason the category exists at all: it needed cellars cold enough to hold for weeks, so it stayed a regional Bavarian habit until refrigeration made it possible anywhere.

• Pilsner - pale lager, crisp, noticeably hoppy. The template most mass-market lager copies.
• Pale ale and IPA - hop-forward ales. IPA is stronger and more bitter historically; the modern hazy version trades bitterness for aroma and tastes almost like juice.
• Stout and porter - dark ales from roasted malt. Coffee, chocolate, sometimes a dry mineral finish.
• Wheat beer - a large share of wheat alongside barley. Hazy, soft, and in the German version strongly banana-and-clove from the yeast.
• Sour - deliberately acidified, by wild yeast or bacteria. The closest beer gets to wine, and the one to put in front of someone who says they don't like beer.

New Zealand hops are a genuine speciality, and one variety made them so. All three below come from Nelson, which grows nearly the whole crop.

• Nelson Sauvin - released in 2000 and named after the grape. Tastes of Sauvignon Blanc: gooseberry, white grape, passionfruit. Nothing grown anywhere else does.
• Motueka - the same white-grape thread with lime on top, the crushed mojito kind.
• Riwaka - grapefruit and cut grass. Low in bittering acid, so it goes in late or as a dry hop, for the aroma.

What you taste in a New Zealand pale ale is usually one of those three - wine, lime or grapefruit - over a malt that stays out of the way. Emerson's in Dunedin was the first of the modern breweries, in 1991, and is still the one to hand someone who wants a classic style done properly. Garage Project's Pernicious Weed is the Nelson Sauvin showcase, a double IPA that tastes like a hop field. Panhead's Supercharger APA is the everyday version of the same idea, and their Port Road Pilsner shows what the hops do in a lager, where there is nothing to hide behind. The hops travel further than the beer does: at the Marathon de la Bière in Montbrison, a small town in the middle of France, I came across a local brewery using them.