Rock Bottom's Eat a Bale o' Hops from the OBF program

There are those who go to the Brewers Festival to get trashed, and there are those who go to the Brewers Festival to geek out. There are also those who go to the festival not knowing what they’re looking for, casting about for something to pull them in and trying not to be overwhelmed by the choices. That’s how I was last year. I’ve learned a lot in the last month and I’ve found that my experience at this years festival is a bit more manageable.

Your greatest tool for conquering the festival is the festival program. Not only does it offer tantalizing beer descriptions, in most cases it also offers the beers vital statistics in the form of IBU, ABV, OG, and FG. If you’re not a beer geek, those acronyms and the numbers beside them might as well be crude drawing of genitalia for all the good they do you. However, if you know how to interpret those numbers, and combine them with the beers description, you’ll have a much better idea about what you’re getting yourself into before you give up that precious wooden tasting token.

Please note that this is the geekiest beer post I’ve ever written, and I’ve done my best to simplify the information. I completely expect that there will be greater geeks than I who will call “FAIL”. But I ask if you call “FAIL” that you clarify the information that I screwed up in the comments section below.

I attempt to explain the numbers after the jump! It's a madcap beer adventure!

IBU: This stands for International Bittering Unit and is linked to the amount and type of hops used in a beer. Generally, the higher the number, the hoppier and more bitter a beer is going to be. But do not let this number fool you! There are some beers that may have a high IBU, but lack the astringent bitterness that you might expect. For instance, Rock Bottom’s Eat a Bale o’ Hops uses a shit-ton of hops, and has an IBU of 80. Despite that, it’s a very well balanced beer with a very mild bitterness. Much of the reason for this is that different hops have different levels of Alpha Acid, which are the resins responsible for hops bitterness. Low alpha acids mean less bitterness. So, if you happen to be drinking a high IBU beer, but don’t experience very intense bitterness, you can turn to your layman companions and say, “They must be using a low alpha hops like Crystal.”

ABV: This is the easiest number to understand. It stands for Alcohol By Volume and is a measure of how much a beer is going to affect your consciousness. A higher ABV beer will get you drunker, quicker.

OG and FG: The numbers associated with these two acronyms indicate the beers Original Gravity and Final Gravity. These are, by far, the geekiest numbers in the entire program. If you know what they indicate, it can offer clues to everything from mouthfeel to alcohol content. They do not affect how fast your beer mug will hit the ground after you’ve been jostled by an excited festival goer.

I offer this information with the caveat that it is highly simplified. Beer does not always behave as you might expect and there are always exceptions. Now, the gravity of a beer is essentially a measure of that beers density (relative to the density of water, which is 1.0 at 60 degrees Fahrenheit), and is largely based on the amount of sugars present at whichever stage the beer is being measured.

Original Gravity (the OG) is a measure of the beers specific density before fermentation. This number is an indication of how much sugar the yeast has available to convert into alcohol. Beer with a higher OG before fermentation is likely to finish with higher alcohol content. Strong beer like Bocks and Belgians will have OG’s in the range of 1.060 to 1.075 (that is 1.06 to 1.075 times more dense than water), while beers that are less strong, like some wheat beers and bitters, can have an OG from 1.020 to 1.040. Just remember, the higher the number the more sugar a yeast has available to turn into alcohol.

Some additional magic occurs when you combine the OG with the FG, or Final Gravity. The Final Gravity is the measure of the beers density after fermentation and indicates how much sugar is left once the yeast has done its thing. The difference between OG and FG will help determine how productive the yeast has been in converting the sugar, and in turn, how alcoholic that beer will be. The difference will also help in determining the beers body and dryness. Generally, a beer with a higher FG will have a fuller body—more unfermented sugars means more density. If the difference between the OG and FG is very high, it can mean that the beer will be a bit more dry: As yeast converts sugar to alcohol, it also releases carbon dioxide, the gas responsible for a beers effervescence and brightness. But these are merely basic guidelines. There is so much more that determines mouthfeel that these numbers just can’t give you. They are simply hints to the possible experience of a beer.

Correlating these numbers with your experience of the beer can be a nice way to augment your tasting notes, and I’d encourage anyone to consider them when first perusing the festival. But after some thoughtful tasting, I’d suggest you find something you like and just go with it. Your palate will become pretty unreliable after around five beers. Start as a geek and then switch to debauchery. That’s the way I roll.