Hops

Does Sahti contain hops? Usually only very little, sometimes none at all. The BJCP style guidelines list a bitterness of 0 to 15 IBU, a value that a Pilsner exceeds by two to three times. IBU is a measure of bitterness: the higher the number, the more bitter the beer tastes.

Juniper, known in Finnish as kataja, takes the place of hops. The branches sit in the trough through which the wort flows, releasing resin, tannins, and a woodland aroma. Some brewers also add juniper berries. The bitterness this creates is soft, carrying a fresh, slightly pine-like note.

Hops are barely grown around Lammi and Sysmä. Where they're needed, they're usually bought in, and home brewers use only a small amount, more for flavor and preservation than anything else. No particular hop variety belongs to Sahti tradition, and there's no rule about hop provenance either.

There's a practical reason juniper ends up in the beer. Its resin and tannins have a mild preservative effect, and where hops were scarce, people turned to what grew in the forest instead. Juniper grows everywhere in Finland, on heaths, by lakeshores, and at forest edges.

Among brewers, a simple rule applies when cutting the branches: the juniper must be fresh and well washed. Old, dry branches taste musty, and too many berries make the beer bitter and harsh. A good Sahti should recall forest air after the first sip, without tasting like gin.