We’ve come to the next most exciting ingredient in beer making, and that is the yeast! So wtf is yeast and what is its role in making this marvellous beverage?
To put it simply, these little creatures are alive and they love the sugary water (refer to previous article on Malt here) so much that they slurp it up, digest it and pees out alcohol, burps bubbles and sweat different smells (or aromas). Really, we’re not joking. These little bad boys are alive and if they aren’t happy or healthy, they are not going to produce good beer.
This is the part where most articles go really crazy and scientific with all the weird ass strain names and temperature they love to thrive in, but screw that. We want to be basic, keeping it simple so that everyone can understand and just enjoy the pint that these microorganisms churn out.
Step back from the style-specific strains and look at the beer family tree, and there are essentially just three major species: ale yeast, lager yeast and wild yeast (and bacteria). While they are kind of similar, they do have some distant relations and breeding history, hence they live and behave differently.
Ale yeast prefers to ferment at warmer temperatures and are behind some of the prominent styles such as Hefeweizen, Witbier, Saisons and most other Belgian styles as the warmth helps produce strong aromas in those styles.
Lager yeast on the other hand prefers cooler temperatures, typically producing fewer esters. The ability to ferment at cold temperatures plus the Bavarian way of storing beers for an extended amount of time, created the perfect combination to produce Lager. The time needed to mature also allowed any potentially negative characteristics given out by the yeast during fermentation to be reabsorbed, leaving a better tasting beer.
Wild yeast is the third family that produces a more rustic and “wild” collection of flavours and aromas. But don’t get it mixed with the other kind of yeast that affects the nether regions, that one cannot drink la sial, although got “flavours” also.
These wild yeast produce varying characteristics, sometimes being more earthy, funky, and barnyard-like flavours, some people call it the “smelly armpit” smell. We don’t know how many armpits they smell to get that reference la seriously. Regardless, wild yeast can ferment over a longer period of time to produce an overall drier and often, a more complex beer.