efficiency

[alefric]

Please can someone explain about mash efficiency and tell me how i would know what mine is (i.e how do i test )

[BigEd]

Mash or conversion efficiency is the percentage of potential sugars that your brewery extracts from the grist. The best way to find your efficiency is to run your numbers through one of the brewing software programs. Most recipes seem to be written for an efficiency of 75% so that should be your ideal target. If you get less don't worry, with experience your percentage will rise. What is probably more important than the raw number is a consistency in your process. Knowing that you can expect to hit a target number is important to recipe formulation and brewing the beer you want to make.

[hoppingMad]

For several reasons, some folks prefer not to run software for brewing. If this is you, lets know and someone will provide a 'rule of thumb' method for you to work out your efficiency.

If however you think you might like to give software a try, have a look at this http://www.beertools.com/
Personally I found BeerToolsPro easier to use than Promash, but I may be thick, and one may well suit better than the other. (Usually its just the one thats downloaded first.)

[Buzz]

Someone may correct me if I'm wrong but, I believe there is a difference between mash efficiency and brewhouse efficiency. The 75% referred to in some recipe books is the brewhouse efficiency.

It's quite easy to calculate manually - if you look halfway down the page here, you'll find all the info and an example.

[ade1865]

is mash efficiency dependant on the brew length achieved at the end, rather than that intended? Basically I went along with some basic figures for loss due to evaporation and trub and hops etc because I was using the system for the first time. Unfortunately I forgot to properly measure the volume of the FV, so I've no idea really how much I actually collected. Something to remember for the second brew

So i assume that the OG will get denser as evaporation occurs, and therefore artificially improve your efficiency?

Er, if u get my drift?

[Jim]

is mash efficiency dependant on the brew length achieved at the end, rather than that intended? Basically I went along with some basic figures for loss due to evaporation and trub and hops etc because I was using the system for the first time. Unfortunately I forgot to properly measure the volume of the FV, so I've no idea really how much I actually collected. Something to remember for the second brew

So i assume that the OG will get denser as evaporation occurs, and therefore artificially improve your efficiency?

Er, if u get my drift?

You have to know your final brew length to calculate efficiency, but you won't automatically have a higher efficiency just because you end up with less in th FV. It depends on how the volume has been reduced; evaporation loss doesn't affect efficiency at all, whereas wort left in the mash tun ullage space and in the boiler and stuck to the hops will affect it.

[alefric]

thanks everyone i'll try the beertools software

[Aleman]

Mash efficiency tells you how much extract you got out of the mash tun (Gravity in boiler Times Volume). so Gravity in boiler = 1.040 Volume = 30L Extract = 40 * 30 = 1200. Now If that was provided from 5Kg of Pale Malt (Potential ~ 1.038) At 100% efficiency I should have got 63 * 30 = 1890 so my Efficiency is 1200/1890 ~ 63%

Now the brew house efficiency is the same figure but in the FV, which accounts for losses to the hops and trub etc and will be less than the mash efficiency . . .unless you add sugar adjuncts

Daab explains this so much better

[brewzone]

You do Yourself an injustice Aleman

That it a pretty concise explaination mate

[Aleman]

Problem is that I got the potential figures all wrong, and missed a step in the calculation as you don't really see where that figure of 63 comes from. If I get time I'll try and put together another example, but I have all these wedding photos to Photoshop and get on the web . . . She has banned JBK until I do that

[brewzone]

It's the withdrawal symptoms setting in Aleman!

[Aleman]

Ok 1 kilo of Malt theoretically yields 296 Degrees/Litre at 100% efficiency so 5 kilos gives 5 * 296 = 1480 at 100%. If I collected 30L of wort @ 1.037 the mash efficiency would be (30 * 37) / 1480 or 1110 /1480 or 75%.

So that goes into the Boiler, and Hops are then added, and the boil starts, sugars are added (possibly). You then drain the boiler and chill the wort. Measuring the gravity at this stage and calculating the figures again gives say 23L at 1.044 (1012 extract giving 1012/1480 or 68% Brew house efficiency ).

This is where I think a lot of brewers possibly get confused (Just like I did ) I quote my MASH efficiency when I give a recipe, as that is what I got with the recipe, if you know your average then you can convert the recipe to your plant. There is little point in quoting the brew house efficiency as that is individual to every brewery.

This is one of the things I suspect happens when I quote an efficiency of 85%, and another brewer is only getting 65% . . . . My figure is the mash efficiency and my friends is brew house efficiency.

Hopefully this is clearer

[Buzz]

Excellent Aleman. I always worry that my brewhouse efficiency is 60% when others quote 75/80% but, if the dead space in my boiler is bigger than most, that could be skewing my figures as I'm losing so much volume at the end.

I'm going to measure my mash efficiency next time to see how that compares. That will give me a better idea of how well I'm doing in terms of getting the most from the malt.

In view of this, recipes in books like Wheeler's and Ollosson, if they are based on 75% would you say that was mash rather than brewhouse efficiency? In fact, I guess Graham could answer that if he's about

[clogwog]

Of course, if you are getting a large gap between your mash efficiency and your brewhouse efficiency, then it should set you on a path of looking at your set up to see where you are losing the efficiency you have worked so hard to get.
The difference between mash and brewhouse efficiency is really only down to what you lose in trub and dead space etc from the kettle to fermenter, and to losses in the chiller.
Boil off evaporation does not reduce it, as that increases the gravity of your wort through a process of concentrating your wort.
It can't magically disappear, so if it's not in your fermenter, you have left it behind somewhere in your process.
Reduce those losses, and your brewhouse efficiency will improve.

[Aleman]

In view of this, recipes in books like Wheeler's and Ollosson, if they are based on 75% would you say that was mash rather than brewhouse efficiency? In fact, I guess Graham could answer that if he's about

I have always assumed that they were mash efficiency, and when I was writing my brewing spreadsheet Graham supplied me his recipe database used in the books, and my figures agreed with his . . . . I'm now waiting to be shown to be an ass