John Palmer vs BeerSmith Efficiency Question

[scruff311]

I just read the section on All-Grain Brewing by John Palmer and saw that he has a somewhat simple equation for calculating efficiency shown here at bullet 14: http://www.howtobrew.com/section3/chapter18-6.html

I used this formula for my last couple of brews and found my numbers were horrible (22-24). I used the pre-boil gravity at a temp of ~150 F (I assume this is the gravity that should be used).

However, when I calculate my mash efficiency using BeerSmith I get ~75% which is pretty good. I was taking this gravity with a sample that was cooled to room temperature though.

Am I taking gravity at the wrong temperature for one of these methods?

 

[ajf]

You're comparing apples to oranges. Beersmith reports efficiency as a % of the theoretical maximum efficiency. Palmer's method calculates points per gallon. You can make a reasonable approximation of % efficiency by dividing his number (22 - 24) by 36.
The other thing, is that you should take hydrometer readings at thy hydrometer calibration temperature (usually 60 F). Taking a hydrometer reading at 150F will give you a very inaccurate figure.

-a.

 

[scruff311]

Ahh ok. Palmer simply states "Measure the gravity in the boiling pot" which implies just dropping the hydrometer in the kettle after sparging is complete, hence a temperature of ~150 F.

So in general, when taking any gravity reading (pre-boil, post-boil, etc) should you always try to get the sample to ~60 F?

 

[duboman]

There is a known issue with the way BeerSmith calculates efficiency and it has been discussed at length in the Software forum, primarily by a poster-CWI. Follow this link and scroll down to his post. You can also search CWI, he/she has written at length in various threads regarding efficiency settings as well as solutions and work arounds.
https://www.homebrewtalk.com/f84/beersmith-head-scratcher-problem-357979/

 

[scruff311]

Thanks for that link. It definitely seems more straightforward to configure BeerSmith that way. I always hated having to fuss with the Brew House Efficiency to get the Est. Mash Efficiency to match what I get with my system.

I'd still like to know as a general rule of thumb when measurements, Jim Palmer or otherwise, call for a pre-boil gravity reading, should you cool your wort sample to the hydrometer calibration temp (~60 F)? I get very different Mash Efficiency numbers depending on whether I use a sample at ~150 F or ~60 F (naturally).

 

[duboman]

Thanks for that link. It definitely seems more straightforward to configure BeerSmith that way. I always hated having to fuss with the Brew House Efficiency to get the Est. Mash Efficiency to match what I get with my system.

I'd still like to know as a general rule of thumb when measurements, Jim Palmer or otherwise, call for a pre-boil gravity reading, should you cool your wort sample to the hydrometer calibration temp (~60 F)? I get very different Mash Efficiency numbers depending on whether I use a sample at ~150 F or ~60 F (naturally).

When checking gravity it is best to have your sample as close to 60 as possible as any adjustments made for temps of 100+ are not very accurate.

Many people will use a refractometer for this purpose. Personally I take a quick sample and throw it in the freezer for about 10-15 minutes to chill while the wort gets to boil.

 

[InLimbo]

Ahh ok. Palmer simply states "Measure the gravity in the boiling pot" which implies just dropping the hydrometer in the kettle after sparging is complete, hence a temperature of ~150 F.

So in general, when taking any gravity reading (pre-boil, post-boil, etc) should you always try to get the sample to ~60 F?

For on-the-fly gravity readings, I'd highly recommend investing in a refractometer. No waiting to chill a sample and you get almost instant gravity readings as well.

 

[cwi]

After you break your hydrometer, post pics in the broken hydrometer thread, then go buy a refractometer. You can find them for ~$30, and they are the same as the LHBS $60 ones. Go off the Brix/Plato scale and convert to SG using an online converter, or mult by .004 and add 1 (i.e. (15 x .004) + 1 = 1.060) for ball park numbers. Refractometers aren't a complete replacement, since they don't work post fermentation- at least not without a bunch of effort. They do allow you to limit your hydrometer needs to only the more accurate/precise/readable 'final gravity' range hydrometers.

RE:BeerSmith. It's been awhile since I stirred up that hornet's nest. It was a lot of work, but it looks like it had the desired effect. I just checked some postings, and it seems BeerSmith is hinting he will be adding the ability to base things off of mash eff and batch volume in the kettle. I doubt it will get BIAB calcs right, but the Aussie's have a spreadsheet that will take an almost to scale recipe, and give the amount to up the grain bill by.

Another funny thing during that rantfest was that I mocked BeerSmith for their marketing manifesto of "No formulas!" and "We do the calcs for you!", when the one calc you have to do yourself, and aren't even given a formula or online tool for, is their "Brewhouse Efficiency". Shortly after I posted, a new calc tool quietly appeared on BeerSmith. No fessing up from BeerSmith himself, though. Strange little world over there.

I have hopes for the next version of the free/open source BrewTarget, but the current one does funny things if you play around with a recipe.

 

[BigRedHopHead]

+1 on the refractometer. I use mine for O.G. and F.G. but I use the calculator on Sean Terrill's website to get better accurate FG estimates.

www.seanterrill.com

I also like www.brewersfriend.com for the brewhouse efficiency calculator. easy enough to use from a reliable source.

 

[cwi]

+1 on the refractometer. I use mine for O.G. and F.G. but I use the calculator on Sean Terrill's website to get better accurate FG estimates.

www.seanterrill.com

I have seen/used that guy's stuff before. Smart guy. He has some real good info on his site. I still think it is a bit iffy to use those charts for determining FG down to 0.00X resolution. It is different for different beer styles, so you would need to keep tabs on your own recipes to fine tune the chart. That is the 'extra' work required to use the refract for accurate FG. The refractometer can still be good for seeing if the beer is finished ferm'ing. The charts, and taste, can tell you if it is stuck well above predicted FG.

There is also the issue that the charts are specific to beer, and won't work for other things like cider. For cider, I need to know where it is to stop it early. I have logs to try and relate brix with FG, but it is a guess at this point. For beer I just let it go until it quits bubbling, then give it at least another week to clean up. If it hasn't finished completely by then (~18 days), it wouldn't do any good to know, since I wouldn't try to resuscitate it anyway.

I also like www.brewersfriend.com for the brewhouse efficiency calculator. easy enough to use from a reliable source.

I haven't been to brewersfriend in a while. Last I talked with them, they were going to change 'brewhouse efficiency' to mean 'lauter/kettle' efficiency, or at least add another efficiency field with the option to use lauter/kettle efficiency as the basis for calcs. They saw the light on why 'to the fermenter' Brewhouse eff was a stupid metric, but also have clients who already had recipes based on it. Just like adjusting trub loss in BeerSmith causes a cascade effect on 'to the fermenter' eff, brewersfriend's hop loss compensator (and trub loss field) also has/had issues due to using 'to the fermenter' efficiency.