Brewed a kolsch the other day. Preboil gravity was 1040. However, my post boil was 1080. My burner is like a jet engine and the kettle is a wide 20gal aluminum. Also, I'm only brewing up 5-5.5 gal batches, so, there isn't a lot of liquid in the kettle, relatively speaking. Is it just a matter of vigorous boil off or is there something else amiss?
Overshooting OG, by a LOT
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kiwibrew said:
Removed the wort hot post mash, it was 1034, climbed to 1040 after sitting out for well over am hour. Same post boil, was 1080 hot, climbed to about 1085 after sitting out for well over an hour as well.
chickypad
lupulin shift victim
If you went 1.040 to 1.085 you boiled off more than half of your volume. You say you finished at 5-5.5 gal, did you start with like 11+ gallons? If not something is wrong with your measurements. What was your recipe and expected OG?
chickypad said:
I'm still trying to figure out my RIMS system. According to BIAB app, I used 9.125 gallons of water and 11lbs grain(9.75 pils, 1.25 wheat). Mash tun is a 10 gal cooler. I had to remove about a gallon of water as it began to overflow. I didn't measure my preboil volume(negligent), but, for a kolsch, 1040 preboil is right on. Yes, by the look of the kettle, I boiled off about half. I'm guessing right about 6+ gallons preboil as 11lbs grain holds roughly 2 gals. Only my 3rd batch using this system. OG 1050
chickypad
lupulin shift victim
Well if you boiled down to like 3 gallons that would explain your problem. I take it you topped up in the fermenter. Sounds like a pretty big kettle to do a 5 gallon batch, especially if it's wide. My 20 gal pot boils off 1.6 gal per hr but it's taller and thinner so a little less surface area (how long was your boil BTW?). You might be able to turn down the flame a bit but it's still likely you'll need to up your pre-boil volume. Sounds like you were trying to go no-sparge but I don't think you can avoid it with your system. If I were you I would be anal about measuring volumes for at least a batch or two or you'll never get it dialed in. If you start sparging your efficiency will probably go up too so you'll have to figure that out.
You'll need to figure out your boil off rate so that you can adjust your pre-boil volume.
Also, gravity readings need to be taken at the correct temperature. Most hydrometers are calibrated to to 68F. It should say on your hydrometer.
Also also, you need to stir the wort so that you aren't sampling a higher gravity part of the wort.
Also, gravity readings need to be taken at the correct temperature. Most hydrometers are calibrated to to 68F. It should say on your hydrometer.
Also also, you need to stir the wort so that you aren't sampling a higher gravity part of the wort.
I topped off with 2 gallons, brought the number to 1054. I boiled for 90 minutes as is typical with all the pils in the recipe. I figure to turn the flame down quite a bit. I mean to measure each time I brew, by the time I remember, it's too late. I'll take some time and do a boil off rate experiment with water. The system is pretty much a no sparge system. This is my exact system:
https://www.homebrewtalk.com/f36/mash-bucket-system-399490/
https://www.homebrewtalk.com/f36/mash-bucket-system-399490/
chickypad
lupulin shift victim
Wow, that's a sweet set up. Looks like you could easily add a batch sparge to get your full boil volume. You'll definitely need to for bigger beers. 2 gallon per hour is probably about right for a wide 20 gallon pot - might not be able to get that down too much more. Is the reason for the big pot that you plan to go bigger someday?
chickypad said:
Pot was part of a package I picked up from a fellow forum member. Price was right. I think I'm going to make the move to a keggle, try a one vessel set up. I've done 3 brews with the system, 3 different ways. Hefe I did with no sparge was OG of 1100!!! Then I did a helles with a sparge using beersmith water volumes and hit that dead on at 1050.
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