For my next entry in the Beer Basics 101 series, I'm donning my professor hat to explain two of the most basic yet most misunderstood beer terms: ale and lager. More specifically, what is the difference between the two?
Let me clarify something first: ale and lager are the names for the two subcategories of beer. Every style on Earth (with maybe one or two exceptions) falls into one or the other. I know that these terms can be confusing because they are often misused by people, including breweries because, let's face it, Anheuser-Busch's advertising department might not know much about beer. I've heard brewers and beer drinkers alike speak about stouts and ales as though they're two separate things. They're not. Stout is merely one type of ale. Please remember that all beers are either ales or lagers.
So what defines these two subcategories of the beer world? Well, that's a tough one. There aren't a ton of hard and fast rules that delineate between the two. What is quantitatively different is the yeast. The all-important yeast. In my style overview of German Hefeweizens, I briefly touched on yeast. The importance of yeast in a beer cannot be overstated. It is the metabolism of the yeast that provides alcohol and, therefore, defines beer. No yeast equals no beer. I further argue that yeast is the agent of change that has made beer such a mystifying drink throughout the millennia. It must be remembered that, for the vast majority of brewing history, human beings knew nothing of yeast. Beer dates back at least 6,000 years and likely much farther but it is only in the last few hundred years that we have known that yeast exists. Prior to the invention of the microscope, all beer was spontaneously fermented by wild, unseen yeast. This has enormous importance as pertains to the cultural significance of beer. Imagine you are a farmer who occasionally makes some beer, living in 4,000 B.C.E ancient Egypt. You are well familiar with the otherwise innocuous ingredients of barley and water. But you also know, through some happy accident, that if you combine the benign barley and water and store them for a period of weeks in one specific spot, that when you revisit your beverage you will find it has new, strange, and powerful abilities to alter your perceptions and state of consciousness. Since fermentation is a mechanism as yet unfathomable to you, you attribute these wonderful new properties to powers beyond your control. Perhaps your supreme God, a lesser god of the harvest or the grain, or even to the animus that you believe flows through all living things. It is this spiritual connection that enamors you of beer from your earliest encounters with it. Beer soon takes its place in various ceremonies and rites as a way of reaffirming your people's belief structure. It is through this great importance assigned to beer that beer eventually permeates its way to other aspects of your life and your experience is not dissimilar from the experiences of your contemporaries around the globe. Drinking beer, in this context, is not unlike Christian communion, wherein believers consume bread and wine as literal or figurative representations of Christ. The core of the rite of communion is to establish a connection with Christ, the same sort of connection sought after by our ancient, beer drinking predecessors. Sure, it's easy to dismiss my ramblings as the waxing philosophical of a delusional nerd because today, the magic is gone. We live in the scientific age and understand yeast so well that, like so many other things in our world, we've begun controlling it and bending it to our use. But the cultural history of beer leaves us an important message: that it is important to, at least occasionally, give beer its due deference because our ancestors thought it magical and used it as proof positive of their understanding of the world around them. And all that magic was thanks to yeast.
Whew, now that the flowery, philosophical geeky stuff is out of the way, let's get back on track. Differences in yeast define the difference between ale and lager. Yeast is a microorganism that is a member of the Fungus kingdom. These tiny little fungi do all kinds of things like make bread rise, provide texture and flavor to cheese, make wine, and make beer! It's this last one that I'm focusing on. Varieties of yeast used in beer fall into the species Saccharomyces cervisiae. S. cervisiae is the ale yeast, and all the infinite multitude of ale yeasts are members of this species, even though they have noticeable differences. These differences occur below the species level, similar to all dogs being classified as Canis familiaris. There are plenty of breeds of dog that look and act quite different, but they're all the same species. Same with the yeast. Lager yeasts, notably fewer in quantity, are known as Saccharomyces pastorianus, although this is based upon obsolete taxonomy. Lager yeasts are now recognized as yet another subtype of S. cervisiae, though the old nomenclature is still used.
Strains of ale yeast are too innumerable to name here (new ones are being created all the time) but there are essentially only two strains of lager yeast that produce the overwhelming majority of all lagers. The difference in ale and lager yeasts is that ale yeasts naturally rise to the top of the beer in the fermentation vessel and are thus known as top-fermenting. Additionally, ale yeasts ferment at relatively warm temperatures, around 60 to 65 degrees. Lager yeasts are just the opposite: they settle to the bottom of the fermenter (bottom fermenting) and ferment at cooler temperatures, usually around 45 degrees. Ales also ferment faster than lagers. In fact, the word lager is German for "storage" due to the long fermentation time.
Because of the difference in how they function, ale and lager yeasts have different properties as pertains to final aroma and flavor. Ale yeasts tend to be more expressive and produce a variety of byproducts that lend additional flavors to the beer. Lager yeasts typically ferment rather clean and depend upon the raw materials of malt and hops to do the heavy lifting in the flavor department. Thus, a rule of thumb is to say that ales are typically more flavorful and distinctive, while lagers tend to be more nuanced and easy drinking. This is a major oversimplification, however, and one should remember that there are exceptions to the rules. Kolsch, for example, is a very light and easy drinking, low flavor and mostly inoffensive ale whereas a doppelbock is a rich, malty, sweet and fruity lager. It is also important to remember that while ales are typically more flavorful, both ales and lagers have their place. I don't always want to drink an imperial stout that requires my full attention, ruins my taste buds, challenges my palate, and demands that I drink it in sips. Sometimes I just want a few bottles of a good pilsner so I can kick back and watch the games or enjoy a barbecue. I keep coming back to my mantra and you would do well to repeat after me: Beer should be fun. I hope this entry wasn't too long or complex. I try to keep it light and minimize how much I geek out on things like yeast, but this topic needed some real explanation because so few people really grasp something as basic as the difference between an ale and a lager. I know I said in my last Beer Basics post that I was going to keep these short and sweet. My bad. I hope they're still worthwhile. If you have any suggestions or questions, leave them in the comments. Thanks. Cheers!
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