Ale vs Beer
Are you someone with definite preferences when it comes to beer? If so, you’re not alone. In general, most people who are beer drinkers have one or another they like best. Either they tend to go for ale when they’re out for a drink with friends, or they have a stated preference for lager. Maybe you can even guess whether a stranger is more likely to be an ale or lager drinker because although there are many varieties of each, both these drinks have their own following and culture. But have you ever stopped to wonder what the difference is between ale and beer?
The answer to this remains the same whether you’re talking about a large scale brewery, or the domestic home-brew in your garden shed.
One answer is the yeast. Most people will tell you that if you ask, although it’s actually the yeast is only part of the reason.
Ale is brewed from the yeast type, saccharomyces cerevisiae, which is has been widely used, both historically and globally. It’s a type of yeast that has its pride of place in baking too, as well as in wine-making, and it’s highly resilient and available pretty much everywhere. This kind of yeast can be seen to rise through the body of liquid to the top of the vessel while it’s active, and then finally it sinks down to the base of the brewing container, showing the brewer very clearly when the brewing has ended. That’s very convenient for production since the leftover yeast can then be removed without disrupting the ale. In the past, the removed yeast would then be used to make bread. Impressive recycling! Ale yeast is a fast working ingredient. The movement of the yeast as it works its way upward through the fermenting ale speeds up the fermentation process, meaning sometimes the fermentation of ale only takes a single week. That's fast in the brewing industry.
And then there’s lager. The yeast in this process is saccharomyces uvarum, and it originated in America. The first recorded brewing with this kind of yeast was in Bavaria. Unlike the previous type, this yeast doesn’t rise to the surface and fall again. In comparison with the yeast used in ale fermentation, lager yeast requires much more careful handling, because small variations in taste, quality, and clarity, will be highly dependant on factors such as fermentation speed, the temperature it’s kept in, and so on. The finished product is generally much smoother and sweeter than beer, not because of added extras, but because the yeast itself reacts chemically with some forms of sugar in the vat that ale yeasts don’t affect. The brewing process for lager is slower than with ale fermentation. This type of yeast remains active at lower temperatures than ale yeast.
Hopefully, we’ve whetted your interest in finding out more about the science behind the average drinks menu. If this discussion has left you pining for an ale or a lager, why not give your usual choice a pass this time and try the other. You might find you're a convert.