Yield and Boil Off Thoughts

[NorsemenRugby58]

My question is basically this...I am looking to pich 5 gallons of wort into my fermentor to eventually yield 4.25-4.5gallons of beer.

My mash produced 2.5gallons of wort.
I took 4gallons from my sparge.

My kettle is only 7.5gallons and cant really safely hold any more wort because I end up "boiling" for an extended period of time turning the heat up and down and back up and back down until the wort settles and boil-over is no longer a threat. The end result is me pitching about 4.25-4.5gallons of wort and netting like 3.75-4gallons of beer, which I dont like.

Im thinking a 15gallon boil kettle will solve this problem because I can keep the heat ramped up without threat of boil over and I wont have to play with it as long, resulting in less boil off..

Does this thought make sense or am I going in the wrong direction?

 

[Hex]

I think you can top off your kettle with fresh H2O 15 min before flame out. You could also add pre-boiled water directly to the wort in the carboy. Just make your beers strong and dilute near the end with up to a gallon of water. I boil in a 7.5 gal kettle all the time and end up with 5.5-5.75 gal of wort. It seems your burner or technique is not fine enough to control a boil. There are also products available that help control foam and boil over, Whirlflock? never used it but it's out there...

 

[Hex]

Also, get a spray bottle of water, and keep it next to your boil. When you start to foam up, just spritz the top of the foam, and it will reside. I have been using a hand fan (piece of cardboard) to fan the boil, and it seems to do the trick just as well as the water sprizer.

 

[NorsemenRugby58]

Nice I do have a spray bottle so I'll try that technique...thanks for the help

 

[ThePearsonFam]

I just turn off my heat when I add hops. I stir them in and crank the heat back up. I (personally) don't mind doing it that way but that's just me. I use a 15 gallon keggle and still try to avoid boilover action in order to keep all the hops in the body of the kettle.

 

[ChemEMc]

Im thinking a 15gallon boil kettle will solve this problem because I can keep the heat ramped up without threat of boil over

That was my hope when I went from a 7.5 gal BK to a 15.5 gal keggle. But turns out that 7 gallons will easily boil over a 15.5gal keggle. Found out the hard way...

(I'm using a 5500W electric heating element, the boil over problem is mostly when it first starts to boil and i haven't turned it down from 100% power. Once turned down to 65-70% power it will still go over the 15.5gal top if I don't stir, but not nearly as fast...)

 

[Hammy71]

A bigger pot will definitely help if not fix the problem. Even with my 22+ gallon pot, I still keep the water spray bottle handy (although with a 5 gallon batch, I've never even came close to boiling over). Can't guarantee that a different pot will mean less boil off. I boil off a little over a gallon an hour with my setup. Once you get your new pot/keggle, do a dry run with 6 gallons of water for a half hour. This should give you a good starting point for your pre-boil volumes/boil offs.

 

[NorsemenRugby58]

I know a larger pot will not prevent boil over, even jumping from 7.5gal to a 15 gallon pot.... my point is that for my 5-5.5gal batch recipes...I need to put roughly 7-7.5gallons of wort into the pot pre-boil....see the dilemma? Essentially I have to nurse the pot for an extended period of time until the boil over threat no longer exists....boiling off precious volume (and money) in the process.... I am definitely going to try the spray bottle as I have never tried that technique before. I just want a larger pot so I dont have to nurse the space as much.

 

[ChemEMc]

Oh, i know exactly the delima. I was in the exact same situation boiling on the stove with heat stick and a 7.5 gal pot filled to the brim. I would have to turn it down real low until some boiled off, it was pretty much 90 minute boils everytime. It worked cause I was in an apartment and had no other choice really, when i moved out I upgraded to keggle.

if you have the money and means then a larger boil kettle is much more set-and-forget, i just have to watch the very beginning of the boil to stir or spray the hot break then once it settles (couple minutes) i know I'm good. And I never get it splashing out the top on the keggle.

 

[NorsemenRugby58]

yeah I guess that is my point my boil times were reaching nearly 2hours it got so bad sometimes

 

[ChemEMc]

Also, if you are starting with 7.5 and going down to 5.5 in one hour that's a ~25% boil off rate which is a bit high. If you're like me you are doing it for better efficiency, and my beer comes out great IMHO, but I am looking at my process to try and get the efficiency else where and lower my boil off. It's early to tell, but it looks like I'm getting much better eff with a mash water ratio of 1.5 qt/lb, up from 1.25 (which i think i was using simply because it was the default in beersmith).

 

[NorsemenRugby58]

well I think I am still going to get a 15gal brewpot because it isnt too much money... and I will use the spray bottle technique as I have not used that ever, and I'll see how it goes.

Thanks

 

[jfowler1]

A bigger brewpot is always a good idea.

That said, I think you are fine using your current pot, and I agree with a previous poster, your evaporation rate is way too high. It should be a rolling boil, not jumping out of the kettle. I am going to make a big assumption; you are currently using the Bayou Classic 32-ish Qt Aluminum Turkey fryer. I use the same kettle, and I think it is perfect for 5 gallon batches.

There is a little lip around the top of the kettle, maybe 2-3 inches down, just above the handles. I have not checked this measurement in a while, but I stop the sparge as soon as that lip is almost covered. I believe that just below the lip is 6 Gallons, so covering 1/2 the lip would be about 25 qts. I use a 75 minute boil for Ales. For a lager, I would collect slightly more, maybe 26 qts, completely covering the lip. This way, I can boil 90 minutes and not effect my volume going into the carboy. You can collect more, and boil it down longer, but why? A couple points of efficiency? I think it is more practical to learn your efficiency so it is easier to replicate future batches, and the only way to do this is to collect a predetermined amount of wort pre-boil and measure its gravity. Mine is always 80% pre boil.

As I said, I boil for 75 minutes, and collect exactly 5 gallons into the carboy (again, measure and mark the carboy). About 2 quarts are left in the kettle, so the final boil volume was 22 qts (after starting with 25/26). I think that is a more appropriate evaporation rate, somewhere in the 12-15% range. I collected 20 qts to the fermenter. I add a liquid starter, bringing me up to about 5.25 Gallons in the fermenter. On bottling day, I rack to the bucket, still leaving a quart or so behind, and I am able to fill 46/47 bottles.

It will pay to keep your volumes in check. It keeps you more consistent, and could save you from shelling out the dough for a new kettle.

Joe