Mash efficiency good , but brewhouse bad .... infinite wisdom needed.

[woodbutcher]

let me first say i dont want to be beating a dead horse (too late) .... but i have searched up and down and cant figure out why my brewhouse % is so low . i dont have a problem hitting my estimated OG, and i make good beer, i just have to buy a bit more grain .

but i am the type that likes to know 'why and how' things are working how they are....
so i will start from the beginning.

I have been using beersmith 2 for 5 months now and it works great ... but I just can’t figure something out.
My 'mash efficiency' is usually good from the crush I get from the local beer store, 78-82%, but my 'brewhouse efficiency' is consistently at 64%. I know the percentage since this is how I hit my post boil OGs accurately. I adjust it to 64% so I buy enough grain.
I think it has to do with fermenter losses etc, but let me tell you the equipment I have and I will let you decide.

I am an all grain brewer that makes 5.5 gallon batches with a single infusion mash, batch sparge.
My mash tun is a 70 quart stand up cooler with a 3 tube copper manifold in the bottom. Works great and only lose about .10 from deadspace when draining.

Steps are as follows:
Preheat tun with 1/2 gallon of water for about 20 minutes and then dump.
Heat strike water +13 degrees, dump in tun, stir in grain slowly, and mix well until desired mash temp is achieved.

I let it let sit for 60 minutes and I lose maybe 1 degree. I then vorlauf about 1/2 gallon, pour over grain bed nicely, and then full open drain the tun.
While mash water is draining (5-7 minutes), I have heated up sparge water to 170 degrees. I then add the sparge water, stir it up and let it sit for 15 minutes, vorlauf, then drain.

For a brew kettle, I have a 16" diameter 60 qt (15gal) aluminum big pasta pot with a valve and dip tube running along the sidewall.
My runnings from the mash tun cooler are always spot on with my preboil volume estimates. My mash PPG is always 27-31.

of course , beersmith’s 'estimated preboil gravity' is always wrong since the program thinks I will have like 71% mash efficiency due to my low inputted brewhouse efficiency. . .

It takes me about 20 minutes to go to a full boil from let’s say 140 degree mash water. I consistently set the propane knob to a spot where the BTUs coming out make a rolling boil... not too much.

I start the 60 minute timer right when it first boils, and then add my ingredients. My hot break is so short (foams up for a bit, lower burner, stir for 10 seconds, and resume boil as usual), that I start the timer right when I see the first rolling boil.
The pot will boil off 1.45 gallons in 60 minutes. This may this may tell you how low or high my burner is. It’s a big pot though.
I wort chill and its 65 degrees in 30 minutes with my copper chiller, then whirlpool, let sit for 20 minutes, and then drain off into a strainer that sits on top of my primary bucket.
I have about .45-.50 gallons of waste in the bottom of the kettle that’s left. Not too bad for a 16" diameter pot I think.
Midway through draining the kettle I take an OG sample. And that’s it.

Sorry it’s so long I just want to be thorough. Let me know what you think.
Thanks.

 

[WoodlandBrew]

It's described better in my book, but here are the nuts and bolts:
http://woodlandbrew.blogspot.com/2012/12/when-more-grain-doesnt-add-more-sugar.html

The book has tables you can look up your efficiency based on grain weight and tun volume.

If you are hitting mash temps, stirring well, and holding for enough time efficiency all boils down to water in and water out. For no sparge it's:

Efficiency = water out / water in.

The loss in efficiency is tied up in the grains and dead space.

With a sparge it's a little more complicated, but you will get close with that equation. If you give me the number I'd be happy to calculate what you should get.

 

[woodbutcher]

If you give me the number I'd be happy to calculate what you should get.

sure, what specific numbers we looking for ? i keep all records in my brewsmith notes section.

pounds of grain, water in, water out (preboil volume), preb gravity, etc ....

i plan on buying my own grain mill to eliminate dealing with using the LHBS to crush. he set his at .038" , but who knows when the last time it was calibrated. i like the looks of the Millar's mill , but afraid since the inventor seems to make lots of different inventions (pizza ovens, etc. ) and his warranty is only a year or two.

im confused... if my PPG is 27 or more, doesnt that mean my mash tun , crush , manifold design etc are good to go? i thought the problem would be on my boil rate or anything after dealing with the tun.
thanks.

 

[WoodlandBrew]

I'm skeptical of the ppg calculation. I'm afraid it may be taking your 64% efficiency into consideration.

If you could tell me the volumes of water added and removed at each stage and the number of pounds of grain I will crunch the numbers.

 

[woodbutcher]

all i do to calculate ppg is take preboil gravity x gallons divided by pounds of grain. i do it right after i drain the tun from the sparge . i mix up the water first obviously. i dont use a program to figure it out.

i will give you my last brew i did . maple pecan porter .

13lbs of grain
4.11gal mash water added, then drained. 5.29gal added , then drained .
total mash water collected : 7.75 preboil volume. gravity: 1.046 into the kettle.
according to my math ... thats 46 x 7.75 / 13 = 27.42ppg .. maybe im not doing it right?

boiled for 60 minutes , added 1lb maple syrup at 60min (increased gravity from 1053 to 1058 in beersmith) .

OG at end of boil was 1.057 , almost spot on with beersmith(1058).
6.25gal at flameout (not cooled)
cooled maybe to 6.1gal .
whirlpooled and 5.7 into fermenter bucket (.4gal loss to trub)

 

[WoodlandBrew]

That's correct with the efficiency rolled into the ppg value. The numbers aren't working out for me. Did you happen to record what you got for runnings?

I'm getting 66% pre boil efficiency, 21.5 pppg and that your first runnings are only 1.4 gallons.

 

[woodbutcher]

if you mean runnings from the mash rest compared to the sparge, no i havent... in fact i havent from any of the beers i have made. i guess because im so focused on the total preboil gravity runnings. beersmith does give me a numbers i should hit, and for that beer it was 2.55gal from the first runnings , and 5.29 from the sparge water.

i would assume the runnings would have to be pretty accurate to my ACTUAL runnings seeing how brewhouse efficiency doesnt change the volumes(just checked, changed from 64% to 70%, no change in volumes on the vol tab)

 

[WoodlandBrew]

Thanks!

Okay all the numbers make sense now. It looks like Beer Smith is not adding in the maple syrup to the efficiency calculation but is adding it to the total gravity. Your lautering and conversion efficiency is 91%, but from the boil and into the bucket you are at 73%. (When accounting for the maple syrup, and 65% when not accounting for it)

It looks like the main driver of efficiency is way you are leaving behind after the whirl pool. But I bet it's a nice clean product!

sorry about the formatting.
ppg 30.2 pppg
lbs of grain 13 lbs
water added 4.11 gal
grain absorption 0.12 gal/lb
tun dead space 0.1 gal
grain absorption 1.6 gal
runnings 2.5 gal
sugar in mash 392.6 GP
sugar extracted 234.0 GP
sugar remaining 158.6 GP
water added 5.29 gal
sugar extracted 122.5 GP
sugar remaining 36.1 GP
total runnings 7.7 gal
total sugar collected 356.5 GP
pre boil OG 46.1 G
pre boil Eff 91%
final boiled down volume 6.1 gal
boiled down gravity 58.4 G
maple sugar added 30 GP
adjusted sugar 386.5 GP
pre pitch gravity 63.4 G
final volume 5.7 gal
final sugar in the pale 361.1 GP
overall efficiency 73%

 

[woodbutcher]

that sounds about what i was thinking ... its the almost 1/2gal left in the kettle thats hurting me ...
its weird ... beersmith recognizes the syrup as a grain and that it will be added to the boil , but when i add syrup to the grain bill it increases the estimated preboil gravity ... now that doesnt make sense because when you go under the mash tab, it shows the total grain in pounds MINUS the syrup ( for my example it shows 14lbs of total grain on the first main tab, but 13lbs under the mashing tab). so it knows its not gonna be in the mash but still increases the estimated preboil gravity.

so to make sure my final preboil gravity is on par with what beersmith assumed it would be, i need to minus the syrup out of the ingredient list. this is ok because i only make a few beers with maple syrup. just a weird gliche .

i guess its silly of beersmith to correlate mash eff and brewhouse eff together.
in my case the brewhouse eff is low due to me leaving so much in the pot and that seems like main cause.
also, i need to look at my first runnings volume to make sure its on par with the program.