I, too, am guilty of what I’m about to condemn. I’ve written out my recipes using weight to indicate amount for both malts and hops with no regard for listing my efficiency numbers. I’ve blindly taken a recipe over to my system without at all considering how the numbers might be impacted my system’s individual quirks. Though I’ve done it, I’m here to decry it and call for a change. In order to further unify the community of homebrewing, limit confusion among new brewers, avoid unnecessary conversions based on units or efficiency percentages (not to mention confusion on whether the recipe writer meant mash efficiency or brewhouse efficiency), and to remove variability of a recipe over the years, brewers need to stop thinking in terms of weight. There are other ways to indicate amount, and as a whole, we need to adopt those methods.
Show Your Units
My high school math and science courses ingrained in me the necessity of showing your units. I didn’t much understand the purpose when I was in high school and the word problem clearly only said “inches,” but often, one small, added piece of information (redundant or not) that would help avoid confusion is left out because we don’t think from other people’s perspectives. When a beer recipe is shared, it often lacks the assumed efficiency to achieve those results. This means that one of several things is likely to happen with this recipe, all of which lead to confusion or unnecessary effort.
New brewers sometimes assume that the efficiency given will be the efficiency they will achieve, or they might ignore that number altogether and focus on the units they know—the 10 pounds of 2-row and 2 ounces of cascade. While these units (pounds and ounces) are easily understood, they must be understood in the context of mash efficiency and volumes gathered. Without that context, a brewer can hardly be expected to hit their target gravity. Therefore, it is not uncommon for a new brewer to bemoan their low gravity and wonder what went wrong—after all, they followed the recipe exactly.
Furthermore, when recipes provide amounts only in imperial or metric units, this can be alienating to those who aren’t familiar with conversion factors. While the argument can be made that conversion calculators are readily available online, it doesn’t negate the fact that we have options for a universal brewing language that we aren’t using.
A Matter of Efficiency
As mentioned above, when a recipe gives amounts of malts in the form of weight, it must be paired with the expected efficiency (or at least target OG) in order to matter. The impact of this is not limited to novice brewers who might get confused; veteran brewers who know their system well and know their mash, lauter, and brewhouse efficiencies intimately will likely need to convert the recipe to fit their system in order to brew the beer represented in that written recipe. This means multiple steps for multiple calculations. It would be an inefficient method of communication if I spoke English to someone who is a native Portuguese speaker, as I would need a translator; however, if we both also speak Spanish, the need for a translator is eliminated, and we can communicate efficiently and effectively. In the same way, relying on weight and efficiency will almost always require “translation” from one system to another, but if we have a common unit where efficiency does not matter, expressing that recipe from one person to another will result in a much clearer method of communication.
And this isn’t limited to malt; hops, too, fall victim to the fallacy of weight. Alpha acid content changes across crop years as well as across crops grown in different fields. (Oil content and other elements also change, but since there is currently no method of quantifying these aspects in a recipe, we’ll leave that discussion to others.) This means there is a huge problem if a recipe only indicates “1 ounce of Target at 60 minutes.” Again, this element of weight must be paired with another piece of information (alpha acid percentage) in order to have any true meaning. Again, even when alpha acid percentage is listed in a recipe, some brewers focus only on weight and then wonder why their pale ale is more like a west coast IPA in terms of bitterness (or vice versa). I recently brewed a recipe that listed the 60 minute addition of 1 ounce of Target at 6.7% AA; however, the ounce of Target I picked up from my local homebrew shop was 12.5% AA—almost twice the alpha acid content listed in the recipe, even though it was the same hop variety. Plugging these numbers into the Tinseth formula, there’s a 21 IBU difference between these (24 and 45 IBUs, respectively) for the recipe in question, assuming the full ounce was added for each.
Turn up the Volume
Another important factor in any recipe that utilizes weight to indicate amount is the expected volume. Someone may very easily anticipate 10 pounds of malt to yield a 1.050 wort if they’re brewing 5 gallon batches. It’s a simple matter of course to adjust that recipe to a 10 gallon batch—just double everything. But what about 3 gallon batches? 20 liters? 1 barrel? The math behind adjusting the recipe is certainly not difficult, but it’s unnecessary. There is another method that shirks all need for scaling and allows each brewer the opportunity to apply the recipe directly to their system with no adjustments.
What’s the Solution?
Writing recipes in terms of percentages for the grain bill and IBUs for kettle hop additions is the most universal method of writing a beer recipe. The percentage of each malt can be used irrespective of any variation between system efficiencies and an individual’s desired units (imperial or metric). It can be used without regards to the volume of beer produced. It removes certain elements from the equation and allows simple application to each system without having to refigure anything.
The IBU is not without its faults as a unit of measurement (at least in terms of calculations). However, the (calculated) added IBUs of hops will not change, while the alpha acid content will. Indicating IBUs added per hop addition, as opposed to ounces or grams, removes that variable. Of course, different IBU equations often produce wildly different results, and actual IBUs will vary across systems despite using the exact same hops with the exact same AA%. Nonetheless, I submit that this is still superior to using hop weight in a recipe. Dry hopping is a slightly different story, as AA% is not what brewers are generally concerned about when dry hopping. However, perhaps we could adopt a similar way of indicating amount of dry hops that has been used for hundreds of years: pounds per barrel—or in the homebrewer’s case, ounces/grams per gallon/liter.
While dry hopping does make sense to use weight to indicate amount, it makes much more sense and becomes much more convenient and universal to utilize percentages and IBUs for all other elements in a recipe. It would also be great to start seeing pitching rate and the temperature fermented in more (read, all) recipes, but I’ll settle for one change at a time.