Why is my end wort quantity so low?

[hungrymonkey]

My set up is a 15 gallon hlt, 10 gallon rubbermaid cooler for MT, and a 15 gallon boil kettle.

My dead spaces are 4 cups HLT, 3 cups MT (without tipping the MT), 6 cups BK.

I brewed up a Mojave red recipe, posted here on HBT. With a grain bill of.

82% 8lb 4oz American Two-row
5% 8 oz Caramel/Crystal Malt - 80L (Franco Belges 80L is best)
5% 8 oz Caramel/Crystal Malt - 40L
5% 8 oz Caramel/Crystal Malt - 60L
2% 3 oz Melanoidin Malt
1% 2 oz Carafa II special
0% 1/2 oz Roasted Barley - 550L
Mashed at ~152
60 mins 1.0oz Palisades pellet 8.1
20 mins .5oz Sterling leaf 7.0
10 mins .5oz Willamette leaf 4.5
Rehydrated pack of US-05
Dry hop 7 days .5oz Cascade leaf 7.0


I put the data into beersmith and it called for

3.04 Gallons for the mash
3.97 gallons for sparge

Total of 7.12 gallons of water for a boil quantity of 5.7 gallons into the boil kettle.

I measured out 7.5 gallons of water using a gallon water jug. While I was mashing, I used the gallon jug to measure out an approximate 5.7 gallons into the boil kettle. Which put the cold water level at the closed off port of my BK. It gave me a reference as to where the wort level should be.

After mashing and sparging, the level was to the same point where the 5.7 gallons of water was measured out previously.

I started the 60 minute boil right after hot break, probably took 15 minutes to reach boil.

After my boil, hop additions, etc. I ended up with this. I am guessing 3 gallons with a gravity of 1.058.

I ended heating 3 gallons of water in my HLT to 168, and running it through my grains again. The third runnings had a gravity of 1.010. I did a 20 minute boil, cooled it, then placed it into the fermentor with the initial 3 or so gallons. placing the total gravity to 1.040.


I am starting to think that due to the size of my boil kettle. My boil off is higher. The kettle is 18 inches across, 15 inches deep. Rough circumfrence of 57 inches (measured using a tape measure).

How do I figure out my boil off?

 

[hungrymonkey]

Oh, and this is the second brew with the set up. the first one had similiar results, with even less wort due to me using a 3.5 quart measuring cup and thinking it was a 4 quart. I thought this was the problem.

 

[eastoak]

you can figure your huge boil off into beersmith which means more total water volume in your HLT. i need 8-9 gallons of water in the HLT to end up with 5.5 - 6 gallons in the fermenter. my boil kettles are a 15.5 gallon keggle and a 10 gallon boilermaker on a top tier. the big burner , dry california air and big kettles do a number on my volumes. if i'm brewing on an especially dry, windy day i'll cover the boil kettle until the boil point then i leave it off and don't worry about it.

 

[LakewoodBrew]

in absence of anything else adding more water to account for larger boil off will lower your OG. What was your target? It doesn't look particularly low. Were you shooting for the 1.040? if yes then you need to continue sparging, and increase boil vol. if no, then you have efficiency problems.

if boil off is your problem you can quickly figure that out by measuring how much wort made it to the kettle and what is left after boil. delta is the boil off.

 

[hungrymonkey]

Shooting for 1.053 per brewsmith at 70% effeciency.

Per a google search. the only good way to check my boil off volume is to measure out five gallons and give it an hour boil.

Was kind of hoping for a more scientific type answer

 

[hungrymonkey]

in absence of anything else adding more water to account for larger boil off will lower your OG. What was your target? It doesn't look particularly low. Were you shooting for the 1.040? if yes then you need to continue sparging, and increase boil vol. if no, then you have efficiency problems.

if boil off is your problem you can quickly figure that out by measuring how much wort made it to the kettle and what is left after boil. delta is the boil off.

Lower the gravity of the preboil volume? then the gravity will increase as you boil off the liquid, leaving the concentration of the sugars higher.

I believe that my boil off is around 2.7 gallons per hour. Based off a rough approximation of how much wort made it into the carboy.

 

[boswell]

I'm a slow-kid, but that seems like a LOT of boil off.

 

[hungrymonkey]

I must be slow too.

I ran the temps lower as well. I got a nice rolling boil going. Then adjusted the flame to alightly above no visible boil.

 

[Werbi]

5.7G is a low volume for a 5 gallon batch. I'd expect over a gallon/hr boil off with the surface area in the pot you are using. You didn't say how much wort you sacrificed to trub in the kettle. I leave between 1 and 3 quarts depending on the recipe (amount of break and hops) in the kettle.I wouldn't boil water to measure, just measure on your next batch (which I'd shoot for 6.5-7G boil volume -extra wort means extra beer!). Always measure and take notes and adjust; you'll just need to dial into your system -as long as it is consistent and it sounds like your yield is consistent.

Cheers, Werbi

 

[flananuts]

A lot of it depends on how strong your boil is. I boil approximately 12 gallons on electric and it runs full boil right now. I will boil off 3 gallons in 60 minutes in my keggle. Once your sparge is down near 1.01 IMO there's no reason to sparge anymore. You end up extracting more tannins. If your eff. is way off, which I have had happen before, top up your water into your BK and supplement with lme to bit your desired OG.

How crushed is your grain and what temp do you mash at and what temp do you sparge at? I find a finer crush with less water more eff. and I'll raise the grain temp up to 168 in order to get the grain bed more viscous.

BTW I hit sub 70% efficiency on the first few batches while I fine tuned the mash water, grain crush and process.

 

[snail]

I always take a preboil gravity reading to see if I'm off the estimated preboil gravity. Then I can adjust with dme or add water. Otherwise, if I add it half way or at the end it will mess with my IBUs. Refractometers are sweet!

 

[Yooper]

You started with 5.7 gallons in the boil kettle, but you're guessing you ended up with 3 gallons. Next time, measure carefully so you can see how much you actually end up with.

I have a keg for a boil kettle, and I boil off 1.25 gallons an hour in the summer, and nearly 1.75 gallons in the winter (due to humidity, I guess). Because I have some trub losses, I start with 7 gallons in the boil kettle.

 

[RoadKing]

There is no other way to determine your boil off rate besides actually bringing a predetermined ammount to a boil then measuring it. Now will be a good time to get a stick, dump in 1 gallon at a time and mark it off for future refrence.
Once you do your boil off rate should remain the same, Boil off rate is measured by gallons per hour, Not by %. I boil off 1.9 GPH and on my system I need 13.5 gallons in boiler for 10.5 in fermentor.

 

[logdrum]

When I switched from a stock pot to a keggle, my fermenter volume dropped too. I upped my PBV to 7.5-7.7 gal for 5.5-5.6 gal into the fermenter w/ 1.9 gal boil off. Not sure why there was an increase in boil off, but once I adjusted for it, my volumes have been spot on. I always aim for a bit over volume as well. Also, make sure you mash tun is completely drained.

Sent from my iPod touch using HB Talk

 

[flananuts]

I used my mash paddle as my measuring stick and did exactly what RoadKing suggested. I use it at the end of my boil to bring my post boil volume back up to where I need it if I boil off too much. I agree, refractometers rock!

 

[hungrymonkey]

I just spoke with the vendor who I bought the pots from. The person who replied said they are using the same pots and boil off 4 gallons an hour with a 14 gallon preboil volume. So my numbers are roughly around thiers.

I am going to play around with beer smith and see if I can figure out how to adjust the grain bill to the water quantity and make a 6 gallon batch with a 2.5 gallon per hour boil off rate.

 

[TheMan]

It looks like you have the polarware 15 gallon pot. That's the one I have. I get a gallon per hour boil off. I aim for 6 gallons post boil. So 8 Gallons starting gets me right there.

 

[huge1s]

It looks like you have the polarware 15 gallon pot. That's the one I have. I get a gallon per hour boil off. I aim for 6 gallons post boil. So 8 Gallons starting gets me right there.

If you aim for 6 and boil off 1 per hour.... wouldn't you need 7 gallons pre-boil? or do you do 2 hour boils?

 

[TheMan]

If you aim for 6 and boil off 1 per hour.... wouldn't you need 7 gallons pre-boil? or do you do 2 hour boils?

Ha, you are correct. My post should have said a gallon per HALF hour. My bad!

 

[hungrymonkey]

I am using the morebeer heavy duty kettles. I seem to be having around 2.5 gallons per hour of boil off.

I will brew again next week, and have adjusted the grain bill to reflect a 6 gallon post boil volume. As well as added 2.5 gallons to my pre boil volume. I will measure out how much it actually is. As long as my gravity stays where its supposed to, I should have my answer.

And hopefully it does not swing far to the opposite direction this winter when its cooler out.

 

[ajf]

Shooting for 1.053 per brewsmith at 70% effeciency.

Per a google search. the only good way to check my boil off volume is to measure out five gallons and give it an hour boil.

Was kind of hoping for a more scientific type answer

What could be more scientific than actually measuring it?
The difference between boiling water as opposed to wort will be insignificant.

-a.

 

[DrMaltyVonHopenstein]

Maybe it has something to do with all the empties on the ground?
:cross:

 

[hungrymonkey]

Maybe it has something to do with all the empties on the ground?
:cross:

My recycler will not take glass in the recycling bin. so I use a 5 gallon bucket. Which I used to stand on while I double checked my hlt temps.

I try not to drink and play with boiling liquids

 

[hungrymonkey]

2.1 gallons per hour.

I boiled up 5 gallons of water today and measured the post boil amount.