Dialing in Mash / Brewhouse Efficiency

[CentralNJBrew]

I've had my set up for a few years, and kind of have a sense of how efficient it is, but never really went the extra mile to measure/record data at critical steps.

I attempted to brew an IPA this past weekend, and made a conscious effort to record as much as I could, with the intent on finally breaking through this issue that has been eluding me.

My main question is this:

Can someone help me piece together all the data that I've recorded below to get my brewhouse/mash efficiency AND/OR let me know anything else that I should have recorded to help?

And I'll admit, my eyes always seem to glaze over when trying to attempt to figure this out on these and other forums, despite my best intentions.

And please call me out if I am omitting any critical data, or using incorrect language or methods.

Grain

2 row Pale 7 lbs (37)
Marris Otter 3.5 lbs (36)
Crystal 40 1.5 lbs (34)

My mill setting was 2.0 (I forget at this exact moment if that is in cm, ml, etc)

Also, if it helps;
.5 oz of Nugget and Amarillo at 60 min
.5 oz of Chinnook at 15 min
Target IBU was 63
Yeast will be WLP 001 Cali Ale Yeast
(Still trying to figure out tasty recipies, and just using what I have in stock. So if this grain/hop/yeast combo looks like a loser, feel free to chime in, but my main focus is on the efficiency for now)

Calculating Theoretical Yield
(7lbs x 37) + (3.5lbs x 36) + (1.5lbs x 34) = 436

My desired L:G Ratio is 2.5:1, so 25 quarts = 6.25 gallons

436 / 6.25 gals = 69.76 = 1.070 Target OG

My strike temp water was 170, and Target Mash Temp is 152-154 Range. I have a direct fire system that I constantly recirculate, so as long as I'm close to this temp range, I'm happy. It stayed relatively in that range with much babysitting, so I'll call keeping it stable was a success.

My pH at start of mash rest was 5.4. This was my only pH reading.

For sparge water temp, I put HLT water up to 180. I always try to make the sparge length 45-60 min range. During sparge, mash reached 160-162 range, not the 168 I always strive for. Lasted 40 minutes before I hit my target of 5 1/2 gals in brew kettle. (I'm still dialing in my sparge program a little bit, so I'll take 40 mins for now)

Also, never really though about it, but 5 1/2 gallons is an arbitrary target quantity I picked for BK to deal with boilover issues, evaporation, and beer loss until time to pour in a glass. I'm open to adjusting.

Pre-Boil SG was 1.050

Boiled for 60 mins. 4 Gallons were left in BK. (60 mins of boiling evaporated 1.5 gallons. Is that too much for that amount of time? It is a pretty intense burner)

Post-Boil SG was 1.070. (100%, yay me, but I know that's not true)

I didn't bother to fill BK back up to 5 1/2 gallons because;

1) I wasn't sure when to add water to hit target quantity (before whirlpool, after whirlpool, in FV?)

2) I filter my brew water through a carbon filter straight into my HLT. I could have used that to fill BK once I measure 4 gallons, but would spring water work just as well? I normally use this HLT water to push last of wort through to my FV.

3) Is there a calculation or common knowledge about how much my post boil gravity would have dropped if I added 1 gallon of water?

After transfer to FV, I estimate I got 3.75 gallons through, and estimate after transfer to keg, more gravity sampling, and yeast/trub dumps, ill have about 3.5 gallons left to be enjoyed. 5 gals is my true end goal quantity.

Soooo, anyone want to help me piece this together? Thank you to any and all that help me piece together my efficiency.

 

[doug293cz]

You netted 3.75 gal at 1.070, so you got 3.75 * 70 = 262,5 gravity points into the fermenter. You started with 436 potential gravity points, so your brew house efficiency was:

Brew House Eff = 100% * Net Pts / Potential Pts = 100% * 262.5 / 436 = 60%​

Your pre-boil volume was 5.5 gal with an SG of 1.050. Thus your mash efficiency was:

Mash Eff = 100% * 5.5 * 50 / 436 = 63%​

This isn't particularly good mash efficiency for a fly sparge process. Mash efficiency is a combination of conversion efficiency and lauter efficiency:

Mash Eff = Conv Eff * Lauter Eff, where all eff's are fractional instead of percentages​

To know just where the problem lies, you need to determine both your conversion efficiency and lauter efficiency. Conversion efficiency can be measured using the method here. Then you calculate your mash efficiency as above, and lauter efficiency as:

Lauter Eff = Mash Eff / Conversion Eff​

Conversion efficiency should be 95% or better. Low conversion efficiency is usually due to not mashing long enough for the crush size you use. You can improve by crushing finer (up to the limit where you get stuck mashes), and/or mashing longer. Your mash pH was good, so that's not impacting your conversion efficiency.

Fly sparge lauter efficiency should be better than a batch sparge efficiency for the same grain bill size and pre-boil volume. With your 12 lb grain bill and 5.5 gal pre-boil volume, your lauter efficiency should be better than 80%. Low fly sparging lauter efficiency is usually a result of channeling during the sparge.

The formula for SG change by dilution or concentration (boiling) is:

New SG = 1+ (Old SG -1) * Old Volume / New Volume​

Brew on

 

[jschein]

I did not check the math but what doug93cz said

 

[CentralNJBrew]

Doug, put simply, THANK YOU. And my eyes didn't glaze over . Efficiency is just one of those things I've tried to get together, but just kept slipping through the cracks.

I'll report back to this thread my next brew day in a few weeks.

Again, much appreciated.

 

[doug293cz]

You're welcome. Glad I could help advance your brewing education.

I'll admit that when I was new around here, my eyes would glaze over when folks were throwing around calculations. But, I dug into things, learned the fundamentals behind the calculations, and that provided me with a lot more insight into the brewing process.

Brew on

 

[stg1fuggles]

A couple of observations:
Your mash seems very thin. I usually try for 1.25-1.5 qt/#. For your grain bill i would use 16qts for the mash in.
Your initial boil volume is very low for that amount of grain. You put 6 gallons in the mash and sparged but only got 5.5 gallons out. This tells me you did not sparge enough liquid.
For the next batch check the sg of the liquid at the end of the sparge. You can sparge until sg reads around 1.01 or 1.008.
Sparge volume should be around 1.5x mash volume.

 

[HiImBrian]

A few additional comments:
1) OP what's your process in using your HLT water to push the last bits of your wort to your FV? I run a fairly long hose to my FV and this is an interesting idea.

2) 1.5 gallons of water lost during the boil might be a tad high. It's a good practice to turn your burner down as much as possible during the boil so as to just maintain a light boil. Anything past this is just converting more water into steam.

And now for a question:
1) True or False: this method of calculating mash eff goes out the window if you keep sparging to 1.010 as opposed to sparging until you get your desired preboil volume.

 

[doug293cz]

A few additional comments:

And now for a question:
1) True or False: this method of calculating mash eff goes out the window if you keep sparging to 1.010 as opposed to sparging until you get your desired preboil volume.

False. Mash efficiency = amount of sugar in BK / total potential sugar in grain bill. If you do the calculation in gravity points, then:

Total potential sugar [pts]= Grain Bill Weight [lbs] * Weighted average of potential points per lb
Amount of sugar in BK [pts] = Pre-Boil Volume [gal] * (1000 * (SG - 1) [pts/gal])
Mash Efficiency = 100% * Pts in BK / Potential Pts in Grain​

Brew on

 

[HiImBrian]

False. Mash efficiency = amount of sugar in BK / total potential sugar in grain bill. If you do the calculation in gravity points, then:

Total potential sugar [pts]= Grain Bill Weight [lbs] * Weighted average of potential points per lb
Amount of sugar in BK [pts] = Pre-Boil Volume [gal] * (1000 * (SG - 1) [pts/gal])
Mash Efficiency = 100% * Pts in BK / Potential Pts in Grain​

Brew on

hmm totally get it now, since the prevoil volume and gravity are multiplied together.

I've gotta go back and check my notes for my last few brews because I know that Beersmith calculated over 100% for what I believe was my mash eff. After some reading, I found that this was due to me not brewing to volumes but to gravities instead. Obviously, from what you've just posted, there's likely another variable that I'm missing. I'll check back

 

[doug293cz]

hmm totally get it now, since the prevoil volume and gravity are multiplied together.

I've gotta go back and check my notes for my last few brews because I know that Beersmith calculated over 100% for what I believe was my mash eff. After some reading, I found that this was due to me not brewing to volumes but to gravities instead. Obviously, from what you've just posted, there's likely another variable that I'm missing. I'll check back

If you open a recipe design and select the "Mash" tab, in the lower right you will find input fields for "Meas Pre-Boil Vol" and "Meas Pre-Boil Gravity." You need to fill these in with the actual measurements from your batch in order for BrewSmith to calculate your actual mash efficiency. These input fields are repeated on the "Fermentation" tab, but in the upper left. Right under those are input fields for "Measured Batch Size" (volume in fermenter) and "Measured OG." These values are used to calculate your actual BrewHouse Efficincy.

Brew on

 

[Lefou]

I found out yesterday how mash pH, thickness, and mineral additions will affect conversion. I had nearly a 20 gravity point differential versus collected wort to calculated. It took me a while to realize where the differences came from.

I'm still fiddling with different styles, so that can be a problem when you really try nailing down a definitive efficiency on your brewing setup. When I realized what happened, I had to compensate slightly, but the beer still came in within tolerances.