How do I calculate my mash efficiency?

The easiest way is to use software such as BeerSmith (or pick your favorite). Most software programs will initially assume efficiency of 75%, which is a pretty good average Joe Schmo efficiency – some people are slightly lower and some a bit higher. The biggest factors affecting the efficiency are the crush of the grains, and the volume measurements. If you really want to understand your efficiency then you absolutely must arrive at exactly the volume measurements that the software uses. Otherwise your calculations will be way off. If you nail your volumes, you will likely find your first few batches someplace around 70%, give or take. It will improve with experience as you learn to tweak your process. Or maybe you’ll get lucky and have it at 75-80% right off the bat! That’s the sweet spot. I find that as efficiency gets too high, malt flavors are reduced, and vice-versa. So, if your efficiency seems low, don’t worry – your beer might even taste better that way. It’s more important to have consistent and predictable efficiency than to aim real high on the scale, in my opinion.

So anyway… enter your grain bill and all the recipe parameters into your favorite software. Then measure your pre-boil or post-boil gravity, depending on what is used in the software. Then change the efficiency percent in the software until it matches what you actually got. The result is your own brewhouse efficiency!

If you want more detailed instructions on how to calculate efficiency by hand, I could explain it but it is a little bit complicated – your best bet is to read Designing Great Beers by Ray Daniels as he tells you how to do it in there. How To Brew by John Palmer (also available free on howtobrew.com) will probably give you the same information.

I believe Randy Mosher also has this discussed in his book, radical brewing, and he may even give the points per pound for many different malts too! Whew, once you get that under yer belt, then I feel its second nature in yer brew house and I don’t concern myself with it as much as I did finding it… I could be wrong, so do any of you other brewers obsess with this? Sneezles61

I just wish Beer Smith had a “compute with sensible volumes” setting. When it says I need 3.68 gallons, it’s just ridiculous. No one measures to the hundredth of a gallon, and I’m not into overriding all the computations to use the precision of my measurements. I just round to the nearest quart and assume a sensible +/- for the rest of the numbers.

This one personal pet peeve aside, BeerSmith is an otherwise awesome program. I highly recommend.

Personally I developed my own spreadsheet for volume calculations, and volumes are measured in quarts instead of hundredths of a gallon, which is more accurate and a little easier since my kettle has quart measurements etched into it. For the most part, you really can just eyeball it anyway within about a half a quart and it’s not going to make a huge difference. The big difference is when you’re supposed to have 3.68 gallons but you really have 4.25 gallons or something like that, but then complain that your efficiency isn’t matching up with the software. That’s way off. That’s what I’m talking about. But if you have 3.6 or 3.8 gallons? That’s close enough. You need to get close, within what’s reasonable and without being unreasonable. That’s what I’m saying.

I just wish Beer Smith had a “compute with sensible volumes” setting. When it says I need 3.68 gallons, it’s just ridiculous. No one measures to the hundredth of a gallon, and I’m not into overriding all the computations to use the precision of my measurements. I just round to the nearest quart and assume a sensible +/- for the rest of the numbers.

This one personal pet peeve aside, BeerSmith is an otherwise awesome program. I highly recommend.[/quote]

I do and my volume sensors do as well 8)

Thanks guys.