Author Topic: Mash OG = 1.059... after vigorous boil, OG = 1.067  (Read 1613 times)

Offline wamille

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Mash OG = 1.059... after vigorous boil, OG = 1.067
« on: March 12, 2012, 10:09:18 PM »
Just wondering how there could only be an eight point change in gravity from mash to post boil.  Any thoughts?

Offline morticaixavier

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #1 on: March 12, 2012, 10:12:13 PM »
it amounts to about 10 % boil off. maybe a bit short but... if it seems wildly off I would check your instruments!

Offline tschmidlin

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #2 on: March 12, 2012, 10:25:28 PM »
Hmmm . . . failure to adjust for temp?  Weaker than expected boil?  Shorter than expected boil due to daylight savings?
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Offline wamille

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #3 on: March 12, 2012, 10:45:29 PM »
I boiled the wort (vigorously) for 75 minutes... I lost at least 1 1/2 gallons of water in the boil during that time.  And I waited until the liquid for both was around 70F.  Is 10% boil off average or close to average?  I'm just used to seeing a bigger difference... maybe twice what I got on this brew.  RDWHHB, right?

Offline edvinjonsson

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #4 on: March 12, 2012, 11:22:14 PM »
Was it an 11 gallon batch? I never brew batches that big, but 1.5 gallons of water lost in a 75 minutes boil doesn't seem like a lot for a batch that big, maybe you did need a more vigorous boil. That being said, 1.067 isn't that bad, so yeah, RDWHAHB  ;)

Offline morticaixavier

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #5 on: March 12, 2012, 11:26:29 PM »
for sure RDWHAHB but also check your instruments cause that math doesn't work out unless it was a 10 or 11 gallon batch.

if it's a 5 gallon batch that's 20% boil off and you should have ended up with 1.082 ish on a 10 gallon 1.5 gallons is ~9% which would be around 1.070

Offline wamille

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #6 on: March 13, 2012, 12:11:42 AM »
boiled 8 gallons down to just over 6 gallons... the hops soaked up a good bit too.  i was really expecting a higher o.g..... strange.

Offline morticaixavier

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #7 on: March 13, 2012, 12:17:29 AM »
boiled 8 gallons down to just over 6 gallons... the hops soaked up a good bit too.  i was really expecting a higher o.g..... strange.

hmm

so 8 gallons to 6.75 is 10% and expected OG of 1.070 which is not out of line with your readings.

Offline wamille

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #8 on: March 13, 2012, 12:35:14 AM »
Ok... so I wasn't that far off.  It just seems most of my beers achieve relative higher OG's than this one.  Either way, it should drink just fine... just a lower ABV than I was expecting.

Offline narvin

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #9 on: March 13, 2012, 06:11:11 AM »
boiled 8 gallons down to just over 6 gallons... the hops soaked up a good bit too.  i was really expecting a higher o.g..... strange.

hmm

so 8 gallons to 6.75 is 10% and expected OG of 1.070 which is not out of line with your readings.

8 gallons boiling down to 6.75 is about 15%.  Down to 6.25 would be over 20%.

When you say mash OG, I assume you mean in the kettle before boiling and after all sparging?

My guess is that there was some stratification somewhere and one of your measurements is wrong.
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Offline brewmichigan

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Re: Mash OG = 1.059... after vigorous boil, OG = 1.067
« Reply #10 on: March 13, 2012, 06:13:42 AM »
Hmmm . . . failure to adjust for temp?  Weaker than expected boil?  Shorter than expected boil due to daylight savings?

That happened to me. I was making a beer and started the boil at 1:59am and it one minute it was already 3:00am?!?! Threw me right off.  8)
Mike --- Flint, Michigan