Did my first batch sparge today. Mashed with 6 gals 166* water added about a qt boiling to get 154 and only lost about 2* in hour mash. Put about 4 gals in the kettle from first runnings. Sparged with 3.5 gals 190*ish stirred good and ran off to get 6.7ish preboil. Saved extra wort for future starters. Pre boil temp adjusted gravity was 1.065 recipe target 1.066. So pretty happy with that. Boiled for 1 hour. Chilled with IC. OG 1.072 against target of 1.083. WTH??? Efficiency 59%. How could a 60 min boil only raise gravity 7 points?
did you end up with exta wort in the fermenter?
No 5.25 which is what the recipe was designed for.
your numbers don’t add up you got 4 gal from first running and added 3.5 gal for sparge. you should have got 7.5 into kettle. You had 6.7 in the kettle and ended up with 5.25 so you boiled off 1.45 gals you had a vigorous boil. 14 points sounds about right to me. Oh ok I see you saved .8 gals for starters right? I’m figuring you should of been at about 1.080
Right target was 1.083 but ended at 1.072.
My first all grain, which was a batch sparge, came in low gravity too. My culprit was a poor crush - uneven with too many mostly intact grains and minimal flour. Also, was your sparge 190F after stirring in? It shouldn’t go over about 168F. Also, batch sparging to 1.082 without adjusting water chemistry I’d shoot for about 60-65% brewhouse efficiency, so you’re in the ballpark. I think 7 points is a decent raise for a 60 minute boil, since it is full volume boil.
Looked like a pretty good crush to me. I was originally thinking I’d BIAB this but the grain bill was too large. My LHBS crushed it, I think he said he set it to .37?
No it was just under 168 after adding about a qt of cold water as well and I did adjust water chemistry per Brunwater in the mash and the sparge. Could the fact that I ended up with almost a gallon extra second runnings be a factor? Would the second runnings have been more concentrated if I’d sparged with less? Though my pre-boil gravity was almost spot on. That’s what confuses me here. Not really a big deal as I’m sure it will taste great. Just want to get better at this.
Expecting to gain .018 points from an hour boil is a pretty lofty goal. Not sure how your recipe could have made that big of a jump. I usually expect a jump of 10-12 points with a 60 to 70 minute boil.
It should be a linear % based on starting gravity if the intensity of the boil is consistent between batches
According to a calculator at brewheads.com
Brewheads.com - <?=$pagetitle?>
, your assumption of a 6.7g/1.065 solution would boil down to 5.25g/1.083 is correct.
So why didn’t you get a 1.083 solution?
I see 3 issues:
Temp correcting the preboil gravity. Just not as accurate as taking the reading at the correct temp for the hydrometer.
Your starting volume as you said was 6.7 ish. Error point.
Ending volume. Are you 100% certain it was 5.25g and was the temp what the hydrometer is designed for? Another set of error points.
Conclusion: If your starting volume/gravity was 6.7/1.065, the difference between an ending gravity of 1.083/1.072 is ~.8 gallons.
Are you capable of measuring your preboil and post boil volume to within .40 gallons? Depending on the vessel, that could be 1/4".
edit: spell check.
Looked like a pretty good crush to me. I was originally thinking I’d BIAB this but the grain bill was too large. My LHBS crushed it, I think he said he set it to .37?
No it was just under 168 after adding about a qt of cold water as well and I did adjust water chemistry per Brunwater in the mash and the sparge. Could the fact that I ended up with almost a gallon extra second runnings be a factor? Would the second runnings have been more concentrated if I’d sparged with less? Though my pre-boil gravity was almost spot on. That’s what confuses me here. Not really a big deal as I’m sure it will taste great. Just want to get better at this.[/quote]
Looks like Nighthawk did the math. The point is that, yes, any time you end up with additional sparge runoff that you did not build into your recipe, especially + 1/2 gallon, your OG will drop below target, unless you got better efficiency than you had anticipated. To hit my target OG, I have sometimes extended my boil if I got too much runoff, but it all went into the kettle. I still use ProMash and following my brew session always utilize its Efficiency calculator to see exactly what my efficiency ended up after inputting the total volume of wort, and losses due to wort left behind in kettle, mashtun, elsewhere. And of course, the higher OG beer you make, the lower the expected efficiency although YMMV.
Looked like a pretty good crush to me. I was originally thinking I’d BIAB this but the grain bill was too large. My LHBS crushed it, I think he said he set it to .37?
No it was just under 168 after adding about a qt of cold water as well and I did adjust water chemistry per Brunwater in the mash and the sparge. Could the fact that I ended up with almost a gallon extra second runnings be a factor? Would the second runnings have been more concentrated if I’d sparged with less? Though my pre-boil gravity was almost spot on. That’s what confuses me here. Not really a big deal as I’m sure it will taste great. Just want to get better at this.[/quote]
Looks like Nighthawk did the math. The point is that, yes, any time you end up with additional sparge runoff that you did not build into your recipe, especially + 1/2 gallon, your OG will drop below target, unless you got better efficiency than you had anticipated. I have sometimes extended my boil if I got too much runoff, but it all went into the kettle. I still use ProMash and following my brew session always utilize its Efficiency calculator to see exactly what my efficiency ended up after inputting the total volume of wort, and losses due to wort left behind in kettle, mashtun, elsewhere. And of course, the higher OG beer you make, the lower the expected efficiency although YMMV.[/quote]
Second running would have no effect on the 1st beer, if the volume/OG are correct on the 1st runings.
I see this as mostly volume measurement error, and slightly a temp/hydrometer error.
ok, I see your point if the last .8 gallon sparge runoff had not been mixed with the mash runoff, although there would have been some dilution to total points anticipated from the sparge due to adding too much sparge water, although you’re right - I’m not paying much attention to the math on this. Instead talking basic assumptions re: process.
when i do a big beer i sparge with more water than my brew pot can handle, i put the extra wort in a second pot and boil it down on the stove then mix it back in with 15 min left in the boil. This should help get you closer to your projected starting gravity.
I am even more lazy than that. I collect the extra wort separately, and as the kettle keeps boiling down I keep adding it to top up the kettle, and adjust total boil time as needed to get the target volume.
All very insightful comments. My measurements were not very precise once all the wort was collected in the pot. I have marks on my spoon and that carboy is only marked at 5 gallons. I should make a mark for 5.25. If I compare the amount above the 5 gallon mark in that carboy which is a 6.5 gallon to a half gallon mark I have on a 6 gallon carboy…I probably have more than 5.5 in there…mystery solved…guess I’ll be marking the carboys more precisely for future reference.
The temperature hydro correction error makes sense too, I’ve read that before. So basically if I’m going to be concerned with my efficiency and hitting target OGs I need to be more precise in my measurements of volume and gravity at correct temp. Makes sense.
I like the suggestion to boil down and add back some of the extra wort to increase gravity but in this case I probably could have just boiled another 15 minutes and I would have come closer to hitting my target and still put plenty in the fermenter.
The good news is the starter I made with Wy1084 harvested from an earlier batch of dry stout is having a grand ole orgy in this fermenter of breakfast stout. I’m gonna go RHAHB and let their ruckus lull me into a nap!
Thanks for all the feedback guys. Very helpful and educational. :cheers:
