Can't get correct brewhouse efficiency with beersmith

[Kyle]

Just finished brewing and am getting a little annoyed with some efficiency issues. My past few brews including the one today I am able to hit my preboil OG spot on but I'm always 2-3 points short of my post boil OG.

According to beersmith my preboil was 1.044 and post should be 1.049 with a 1 gal/hour boil off rate. I got the 1.044 after I finished sparging, but even though I boiled off a little more than a gallon it measured at 1.047. And that's rounding up. What could cause this or is there another setting in beersmith that I can play with so I'm not under shooting everything?

 

[khannon]

Are you measuring gravity at a consistent temp (68F?)

 

[chickypad]

As above it could be a temp issue. Or if you're sparging maybe it's a mixing issue with the preboil wort. If your post boil OG's are consistently a little low I'd just adjust your efficiency to that so you hit the number that counts.

 

[Kyle]

Give or take a couple degrees yeah. Would a few degrees make that much of a difference? I'm using a refractometer btw

 

[Kyle]

Yeah Ill probably start changing the efficiency. I never really minded but it's become so consistent I just want to know a possible cause for this

 

[kh54s10]

Are you starting the boil with the right volume of wort AND ending up with the right volume?

 

[Kyle]

Yup started at 13.5 on the sight glass and ended with just under 12.5 after.. I check the reading as I am filling the fermenters. I fill the first one about half way and then fill up a glass and continue the rest into the fermenter. It's really weird my system is electric so the boils are pretty consistent.

Now that you mention it though maybe I sound try and see if the sight glass markings are accurate. They look even but I bought my equipment from someone else and never really verified the markings

 

[ba-brewer]

Just finished brewing and am getting a little annoyed with some efficiency issues. My past few brews including the one today I am able to hit my preboil OG spot on but I'm always 2-3 points short of my post boil OG.

According to beersmith my preboil was 1.044 and post should be 1.049 with a 1 gal/hour boil off rate. I got the 1.044 after I finished sparging, but even though I boiled off a little more than a gallon it measured at 1.047. And that's rounding up. What could cause this or is there another setting in beersmith that I can play with so I'm not under shooting everything?

You can manually calculate expected gravities with post gravity points = (pre volume/post volume)*pre gravity points

using 13.5gal and 12.5gal with a 1044 start that gives (13.5/12.5*44) 1047

To get the best results from beersmith you need to keep tweaking your numbers until it matches your system. If you are getting within a couple points you are under 5% off, that seems pretty good to me.

 

[Smellyglove]

Do you account for about 3-4% volume shift from cold to hot when measuring the volume?

 

[Kyle]

You can manually calculate expected gravities with post gravity points = (pre volume/post volume)*pre gravity points

using 13.5gal and 12.5gal with a 1044 start that gives (13.5/12.5*44) 1047

To get the best results from beersmith you need to keep tweaking your numbers until it matches your system. If you are getting within a couple points you are under 5% off, that seems pretty good to me.

Didn't know about that calculation that makes sense then. Guess I'll have to go a little deeper into beersmith and get it tweaked properly

 

[ba-brewer]

I would say you are pretty close and don't need much tweaking. If you are consistently a couple gravity points low drop your BHE a point or two and that should bring it in closer.

For me my efficiency numbers got more consistent when I started measuring expected mash gravity to determine when to sparge instead of just using time. I just wish there was an easy way to determine that within beersmith if your are doing batch or fly sparging.

 

[Smellyglove]

If he drops BHE he also drops the ME in BS. He needs to adjust one or more parameters after mashing.

 

[Kyle]

I tried messing with it and yeah the mash eff goes down when the brewhouse is adjusted. I'll just have to play with it otherwise just adjust brewhouse and not worry about mash eff. Mash eff is pretty consistent anyway

 

[ba-brewer]

lowering BHE should result in an increase in your grain bill and that should get your gravity to be closer to the beersmith prediction.

If your volumes are in line with what you entered into beersmith then your BHE is not right and it needs to be adjusted. The ME number in beersmith is determined by the BHE that you enter.

 

[Smellyglove]

But ME is what counts. What if he tried a recipe he's gotten online? Cant nail that with only BHE. And if he wants to adjust during the boil, or before the boil, he need to have correct ME numbers.

 

[ba-brewer]

you can only adjust BHE in beersmith.

 

[chickypad]

I also found chasing the BHE to be too frustrating so I set the kettle/trub losses to zero and adjust the batch size to my post boil size. If I have a big IPA that I know will have a bunch of loss due to hops then I adjust up the batch size. This way the BHE and ME are the same and that I can target consistently.

 

[ba-brewer]

But ME is what counts. What if he tried a recipe he's gotten online? Cant nail that with only BHE. And if he wants to adjust during the boil, or before the boil, he need to have correct ME numbers.

I use beersmith for recipe design and converting online recipes and have never needed to know or adjust the mash efficiency. If you have the grain bill and expected gravities you can adjust to your system.

If you use the formula I posted before you can make adjustment at the pre boil stage without knowing ME.

 

[kh54s10]

I've never even paid any attention to the ME. I set my equipment profile, tweaked it then set the BH efficiency to what makes the preboil and post boil close. I don't think you can ever get it to hit the numbers exactly every time. Things happen that make every brew session a little differen

I am usually in 1-3 points of my target.

On one of my beers I missed my OG by almost 10 points low. In the end it was not what I intended but turned out to be in the top 25% of all my beers.

 

[ba-brewer]

This is a useful spreadsheet for debugging efficiency issues and determining the expected mash gravity before you start sparging.
http://braukaiser.com/wiki/index.php?title=Batch_Sparge_and_Party_Gyle_Simulator
the link to the spreadsheet is broken this looks like the correct one.
https://r.search.yahoo.com/_ylt=AwrSbhg1G4papSoAFBZXNyoA;_ylu=X3oDMTEyOWg2cGg0BGNvbG8DZ3ExBHBvcwMxBHZ0aWQDQjUxOTlfMQRzZWMDc3I-/RV=2/RE=1519029174/RO=10/RU=http://braukaiser.com/documents/batch_sparge_simulator.xls/RK=2/RS=ldQa7cG4OuJbbzBab80YuNAlZQc-

 

[smyrnaquince]

Do you account for about 3-4% volume shift from cold to hot when measuring the volume?

I believe that BeerSmith assumes that the pre-boil and post-boil volumes are both measured at the boiling point. (If you look at the Volumes tab, you'll see that shrinkage due to wort cooling is taken into account *after* the post-boil volume.

I typically assume that:
volume at ambient (room temperature ) * 1.02 = volume at mash temperature
volume at ambient (room temperature ) * 1.04 = volume at boiling