Beer. It’s delicious, easy to make, and it’s been around forever. How long is forever? Try the tenth millennium B.C.! Residue on bowls left behind by primitive cultures of those days suggests people may have consumed a naturally fermenting, wild yeast based, soupy paste which, in fairness, is not beer.
The oldest beer recipes only date to about the fifth millennium B.C. and outline a brewing process vaguely similar to modern day practices. In the case of recipes found in Egypt for example, a mixture of bread and water was heated, stored to ferment, then supplemented with things like dates, honey, and yeast for taste and increased fermentation.
The recipe bears some similarities to modern day brewing but the end result in this case was a thick, dark red brew that tasted more like a fruit drink. No hops, no carbonation. Not exactly what people think of today when they visit their local pub!
Modern beer actually evolved during the early Middle Ages, in European monasteries of all places. In fact, monks were the preeminent brewers of those days and are commonly credited with incorporating hops into the brewing process during the twelfth century.
Hops are small, green, cone-like fruit that give beer its bitterness and even help preserve it too! Specifically, monks added hops to what is known as wort, an extremely sweet, grain derived liquid that eventually becomes beer. The wort is sweet because the beginning of any brewing process, regardless of time period, is essentially about unlocking the sugars in barley grain. Before anything can ‘brew,’ the grains get malted and eventually cracked in order to expose the endosperm, an inner tissue from which wort is derived.
The cracked grains get steeped in hot but not boiling water for around an hour, kind of like making broth. This part of the process is called mashing. The hot water activates enzymes in the cracked grain’s exposed tissue which causes its starches to break down and release sugar. The residual solids get strained out and what’s left is a sweet, sticky liquid called wort that gets boiled. This is where the aforementioned, all important hops come in, contribute their bitterness to the wort, and help create the baseline flavor of beer today!
Like mashing, boiling lasts for an hour, during which time hops are added to the wort. Then comes another round of straining and filtering before the hop enhanced wort goes into storage containers. Yeast gets added, and the fermentation process begins! Yeast is a fungal microorganism of which there are many different varieties.
The most important thing to know in this case is that yeast loves sugar, which the wort is full of. When the yeast digests the sugary wort, it creates alcohol and CO2 as biproducts. Despite the yeast creating carbonation naturally, extra CO2 is sometimes added artificially during the bottling process.
Overall, brewing beer is relatively simple. Malt the grain, mash it, strain it, boil it, throw in some hops, strain it again, throw in some yeast and let it sit for a few weeks. One nuance to keep track of however, no matter the style of beer, is the type of yeast that gets used to make it.
Beer can be altered and amended in innumerable ways at any time during the brewing process, something smaller breweries often pride themselves on, but the basic type of beer produced, no matter the stylistic alteration, depends on the yeast and falls into one of two categories. Ale yeast or lager yeast. So, what’s the difference?
First off, there’s temperature. Ale yeast eats sugar most effectively between 65-75 degrees Fahrenheit. Lager yeast requires cooler temperatures, usually between 38-60 degrees Fahrenheit. In their optimal temperature range, ale yeasts work more quickly than lager yeasts and typically take about seven days to finish most of the fermentation process, though an additional week is sometimes necessary.
Lager yeast works much slower and needs between six to eight weeks for adequate fermentation. The cooler temperatures necessary for lager yeast also inhibit ester production, organic compounds that contribute to the funkier side of a beer’s aroma and flavor. Ale yeast makes a lot of them, along with phenols, which lager yeast makes too.
Ale yeasts are also pickier than lager yeasts, so to speak, and consume a smaller variety of sugars which further contributes to their wilder, more ‘off-flavor’ taste relative to the typically crisper, cleaner tasting lager.
Historically, older European beers were all ales since ale yeast thrives in many of the continent’s climate zones and it wasn’t until the sixteenth century that monasteries started using cold storage techniques necessary to make lagers. Though a worldwide explosion of microbreweries has blessed the market with seemingly infinite variations of beer, the beverage’s time tested, ancient essence, appears destined to remain intact indefinitely.