Now that we have a handle on the first two main ingredients of beer, water and malt, we can talk about the next two ingredients: yeast and hops. Yeast is probably one of the most misunderstood ingredients while hops tend to get all the glory. Let’s dive in.
Yeast is the magic ingredient that makes beer, well…beer. It is what gives beer its alcohol content and also imparts part of the flavor profile of the beverage. Yeast is a microorganism, technically in the fungi family, and there are hundreds of different yeast strains that are used in beer and more are being discovered every year. However, all yeasts come down to two different types: lager and ale yeasts. Ale yeasts ferment at warmer temperatures and lager yeasts at cooler temperatures.
In part 1 we talked a little bit about what fermentation is and to refresh your memory, it is when yeast “eats” carbohydrates (found in the malt) and the by-product is alcohol, carbon dioxide, and heat. As yeast eats the carbohydrates in the malt they also multiply and will continue producing its by-products of alcohol, carbon dioxide, and heat until there are either no more carbohydrates to consume or the temperature either gets too high or too low.
This is why temperature plays a critical role in the fermentation process. If the temperature gets too high, off-flavors are produced that can over power the flavor of the beer and if it gets too low, then the yeast becomes dormant. This is also partly how brewers can control the alcohol content in beer.
Anyone that enjoys a nice, craft beer certainly has heard of “hops”, but what are they and how do they affect beer? Hops are essentially a plant (similar to a vine) and it is the flower of that plant that is harvested for the purpose of brewing beer. This hop flower is what gives the beer it’s bitter taste and aroma depending on when it is added during the brewing process. Hops also act as a preservative, which extends the lifespan of the beer once it’s canned or bottled. Hops for the win!
Now, why do we need to add hops to beer you might be asking? Well, you don’t NEED to add them, but without hops beer would be extremely sweet, boring to drink, and frankly not very palatable. The amount of and type of hops that go into beer can vary wildly from your hopped up Imperial IPA or your crushable lager. That’s right, there are even different types of hop plants, but we won’t go into that today. We even have devised a scale to measure how much hops or how bitter a beer is called IBU’s, but that’s also a discussion for a different time.
I hope these last two posts have helped you understand what goes into making a beer a little bit better and also how there can be so much variance in beer styles with all the combinations and types of water, malt, yeast, and hops that can be used. One reason why I enjoy beer so much is because no matter how many I may try, I will never be able to try them all. It’s never boring and trying new beer truly is a flavor experience!