Batch Sparge, Missed OG, Process Problems

Hi all, I brewed an IPA the other day with 11 lb. of 2-row and 1 lb. of Caramel 40. I have the recipe in BrewBuilder on BrewMaster's Warehouse and it says for a 5 gallon batch at 70% efficiency I should hit an OG of 1.062. I took a gravity reading before pitching, but after I collected 5.2 gallons of chilled wort from the kettle. The OG was 1.054 (temp corrected for 74*F). This is my 4th all-grain brew, and I've had problems hitting my OG every time. I was wondering if anyone out there could help me find what I'm doing wrong and maybe give me some things to focus on the next time I brew. I'll probably be making a couple more single-hop IPAs just so I can get more comfortable with this.

My setup:
Two 5-gallon, round, beverage coolers. I use them for Mash Tun and HLT. Mash tun has an SS Braid. Both have ball valves.
1 keggle. Just found a deal on Craigslist, only used it for this batch. Before now I've been using an 8 gallon kettle.
PID and Immersion Heater/Bubbler from Fresh Meal Solutions.

My Process:
Mash:
Heated 3.75 gallons (1.25 quarts/lb) of strike water in mash tun to 169.
Mashed in and hit target mash temp of 153 for the full hour. Stirred like crazy at the beginning because temp was just over 154, but left it alone for the rest of the mash. Checked after 5 minutes, temp was 153 and it stayed that way the two times I checked after that.
Collected 2.5 gallons of first runnings.

Sparge:
Heated 5 gallons of sparge water in HLT to 187.
Split it into two 2.5 gallon infusions. Stirred mash as sparge water was added in both infusions. Also stirred after both infusions were complete.
The mash temp from the first infusion hit 173F, forgot to check the temp after the second infusion. Also not sure how much the second infusion cooled as I added the first.
Since it's only a 5 gallon cooler I wasn't able to sparge to reach the full 7 gallon boil volume I was going for - definitely should have bought a bigger cooler. Had to add less than a gallon of water to hit 7 gallons pre-boil.
Did not check the pre-boil gravity.

Post-Boil:
Collected 5.2 gallons of wort with an OG of 1.054. Lost most of my volume to evaporation, however, there was a small amount of wort lost to loose whole hops and dead space below dip tube with screen.

Couple of things:

- Next time check your pre-boil gravity (BEFORE you add any makeup water!). This is the best indicator of your efficiency from the mash and will help you in adjusting your recipes in whatever beer program you use (in your case, BMW's Brew Builder).

- The biggest factor that I can see in your missed OG is the dilution of the pre-boil wort with the additional gallon of water. Next time, if you are short volume in the kettle, add the water to the MLT, stir and then drain. Maybe even have an extra pot of water on the stove to provide makeup sparge water.

I use a 5 gal cooler with SS braid to mash, and had eff. problems at first. Adding a mash out @170 for 10 mins brought my eff. up to the upper 70's from the mid 60's. Your mileage may vary...

I understand why you think you're limited to 5 gallons of sparge (HLT size) but it's just as easy to hold an extra gallon or so in a bucket for the 10 minutes. Use that as part of the first sparge and any temp loss would be minimal. You just can't dilute all grain wort and get good efficiency.

1/3 of the difference is in the fact that you have 5.2 gallons and the recipe calculates OG based on 5.0 gallons. 0.2 gallons will cause about a 0.002 SG difference if my calculations are correct. So with that you are 0.004 from the stated. One step closer...

My guess is not enough batch sparges. Instead of doing 2x 2.5-gallon batch sparges, I would go more towards 3x 1.66-gallon sparges. If my numbers are right, you should be easily be able to do 3 batch sparges.

My 12-gallon set-up usually looks like this:

20 lbs of grain. Mash with 5 gallons for apx 1.25 qt/lb. Sparge with 11 gallons (44 qt) at a rate of 9 qt per batch sparge, so I get 5 batch sparges out of the total volume of sparge water. Lose 2.0 gallon due to absorption, leaves 14 gallon to kettle. Boil off 2 gallons, end up with 12 gallons in the fermenters.

If I multiply all this by 5/12 (to make it 5-gallon batches) - will need to be adjusted for evaporation rate. I'm losing about 2-2.5 gallons/hour.

8.3 lbs of grain
2.01 gallon water for mash
4.6 gallons (18.4qt) of sparge, at a rate of 3.75 qt per batch sparge = 4 sparges.

So my bottom line: Your batch sparges are too high in volume. Reduce the volume and increase the number of batch sparges.

M_C

M_C

Hey everyone, I appreciate all the helpful replies. You all basically confirmed what I should have suspected - that my sparge process is shaky.

I can address the sparge volume problem by just using my old boil kettle as an HLT instead of my cooler. (btw, Bobby_M, your all-grain primer is awesome).

I've probably been rushing through the sparge a little faster than I need to. I can easily stretch each sparge out to 10 minutes to try and snag a few extra points. My temperature control is steady enough that I should be able to extend each sparge without my HLT temp dropping too low. How long do you guys stir the mash? Maybe I'm not being forceful enough.

Regarding the number of sparges, this is something I've wondered about. I think I was only doing two because the sparge calculator I used (BrewPal) could split them up that way.

I think I have a lot of different things I can try now to hopefully start hitting my OG. I'd really like to be in the 70s because it seems most recipes are calculated for that.

Thanks again,

If you check out this link:

https://www.homebrewtalk.com/wiki/index.php/Batch_Sparging_Analysis

It's everything you ever wanted to to know about batch sparging but were afraid to ask.

Also, I wouldn't really worry about maintaining a constant temp during the sparges. It's really not necessary since you are just trying to rinse the sugars off the grains.

I'm sorry, you're making this way too scientific. And I bet you're beers are suffering.........relax.

Or instead of worrying about how many sparges (which, by the way add time to your brew day) you can just adjust your efficiency a bit and add some more grain.

Personally, I don't think that switching from 2 batches to 3 or 4 batches is that much of a hassle.

FWIW, my batch sparges take as much time as my fly sparges, about 1 hour.

M_C

Each batch sparge should only take no more than 15 minutes each. Ten minutes to stir and let sit, and five minutes to drain.

If you heat the sparge water while you are mashing, then it is ready to go right after draining the mash.

Ace_Club said:

Each batch sparge should only take no more than 15 minutes each. Ten minutes to stir and let sit, and five minutes to drain.

If you heat the sparge water while you are mashing, then it is ready to go right after draining the mash.

Click to expand...

Or even less time! Pour in the sparge water, stir like your life depends on it, vorlauf, drain repeat. No need to let it sit for any length of time at all- the batch sparging is just as effective by draining right away.

The lowered efficiency in this case is probably because of the lack of volume in the sparge.

no mash out?

my highest efficiency comes when i mash out to about 168 and hold it for 10-15 minutes...

jtakacs said:

no mash out?

my highest efficiency comes when i mash out to about 168 and hold it for 10-15 minutes...

Click to expand...

Mash out is only really necessary for fly sparging to stop conversion. Not an issue with batch sparging.