I’ve been interested in doing 3 gallon batches rather than my usual 5 gallon. I get the gist of scaling down for grains, but I see virtually nothing about scaling down for hops. I’m a little worried about that. Any helpful ideas? I’m now using Brewmaster’s Mash and Boil with a pump. Thanks in advance for replies.
Art
Just maintain the IBU/SG ratio of the original recipe. Scale down the individual hop additions and then adjust as needed to hit the original ratio.
Most brewing software has a scale function. I use Brewer’s Friend and scale it in the software if I’m converting a 5 gallon batch to my batch size.
One thing that does not scale at all is inherent system loss.
This is why I used to get into arguments with people about whether you can simply scale down linearly. If your software has a profile set up with accurate deadspace volumes then the software should be fine to make the appropriate calculation but if you don’t account for deadspace at large volumes and just package what you get then you might be in for a real surprise when that three gallon batch comes out half a gallon short.
That is why I do not use brewhouse efficiency as defined in Beer Smith. Simple points per pound per gallon scales very well. In fact, well enough that brewing software is not needed.
No well-designed system should have significant deadspace volumes. In a well-design mash tun, the deadspace should be insignificant enough that the runoff volume can be closely approximated by taking the strike volume + sparge volume - liquor_remained_by_the_grist. I have never used brewing software for recipe formulation or scaling since I started to brew in 1993 and I always hit my targets. I brew 3 and 5 gallon batches, packaged volume. It is not rocket science. It is just simple brewing mathematics.
Yes, simple, tedious brewing mathematics. The kind of stuff you do over and over so many times you wish someone would automate it so you can spend your time on more interesting things.
Although I do use the BeerSmith brewing software, I always do a double check by doing the hand calculations. What BeerSmith tells me for something like pre-boil kettle gravity at a given efficiency does not always match the hand calculations. I look at my desired OG and back calculate for pre-boil gravity and use that number. It always gets me where I want to be after the boil and i can make any necessary kettle adjustments with DME or whatever, if it looks like I am going to fall short. If I hit my OG within a couple percent, I am a happy camper.
BeerSmith has some idiosyncrasies. That is why I use BeerCAD VR. It is not publicly available yet, but I expect an announcement around the end of the month.
In such cases, you can use a kitchen scale to not make a mistake in the calculations. My recipes always list the pounds I might need for a recipe. So I don’t worry about accuracy when I weigh all the ingredients. Just do not forget that the container that you use also has its own weight. Weigh the hops and the individual additives so that you get the right ratio of ingredients. And you can find kitchen scales even on Amazon. I bought mine from here https://www.amazon.com/Vont-Beautiful-Measurement-Stainless-Batteries/dp/B08SW6F5SZ https://www.vont.com/product/digital-kitchen-scale/