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General Category => All Grain Brewing => Topic started by: gymrat on June 11, 2011, 02:32:35 PM

Title: fermentability question
Post by: gymrat on June 11, 2011, 02:32:35 PM
My wheat beer had an original gravity of 1.053. So I was looking for an FG around 1.012ish. It ended up 1.009. Why did it ferment so far? Not that I am complaining I am just wondering what I did so I can duplicate or fail to duplicate at will. Was it something in the way I mashed it?
Title: Re: fermentability question
Post by: Kirk on June 11, 2011, 02:45:28 PM
Probably was.  What was your mash schedule/procedure?
Title: Re: fermentability question
Post by: denny on June 11, 2011, 02:57:05 PM
A difference of .003 is negligible and I certainly wouldn't worry about it.  Why were you expecting 1.012?  If some software told you that's what you'd get, just ignore it in the future.  An FG prediction by any software doesn't take into account all the variables in a mash.
Title: Re: fermentability question
Post by: bonjour on June 11, 2011, 04:56:07 PM
I'll add that Brewing software only ever ESTIMATES what you will get on your system.  There are parameters you can tweak to come closer, but it is a calculation, not a measurement of that you do on brew day.
Title: Re: fermentability question
Post by: gymrat on June 11, 2011, 05:45:39 PM
Actually I was going by a rule of thumb estimate. I figure 1/4 of last two digits of OG for FG is a good ballpark estimate. And up until now it has been really close every time. I wasn't so much as worried about it as I am wanting to learn from it. The beer tasted really good out of the fermenter before going into the bottling bucket.

As far as procedure I used 5lbs Rahr 2 row and 5lbs Rahr malted wheat. Mashed at 152 for an hour, then batch sparged at 170 for 10 minutes. Ratio was 1.25 qts per pound. I did have 3 stuck sparges and had to empty contents into another container, clean my mash tun, pour contents back in to drain all 3 times. So being precise on proceedures would be pretty difficult.
Title: Re: fermentability question
Post by: jamminbrew on June 11, 2011, 06:09:11 PM
A difference of .003 is negligible and I certainly wouldn't worry about it. 
+1  My beers are almost always close to the predicted numbers, but rarely ever spot on. My FG are almost always lower than predicted.
Title: Re: fermentability question
Post by: morticaixavier on June 11, 2011, 06:26:43 PM
I would guess it has to do with what amounted to a much longer mash if you had to empty your lauter tun and clean it three times.
Title: Re: fermentability question
Post by: denny on June 11, 2011, 06:43:14 PM
I would guess it has to do with what amounted to a much longer mash if you had to empty your lauter tun and clean it three times.

Not to mention a lower temp from doing that.
Title: Re: fermentability question
Post by: morticaixavier on June 11, 2011, 06:44:30 PM
I would guess it has to do with what amounted to a much longer mash if you had to empty your lauter tun and clean it three times.

Not to mention a lower temp from doing that.

So if the OP wanted to duplicate this without emptying and refilling his mash/lauter tun three times would he mash for like 75-90 minute sat 150-148?
Title: Re: fermentability question
Post by: denny on June 11, 2011, 06:46:13 PM
I would guess it has to do with what amounted to a much longer mash if you had to empty your lauter tun and clean it three times.

Not to mention a lower temp from doing that.

So if the OP wanted to duplicate this without emptying and refilling his mash/lauter tun three times would he mash for like 75-90 minute sat 150-148?

Just as a WAG, I'd say 146 for 90 min.
Title: Re: fermentability question
Post by: gymrat on June 11, 2011, 07:58:32 PM
So a longer sparge at a lower temperature makes the beer more fermentable?
Title: Re: fermentability question
Post by: jamminbrew on June 11, 2011, 08:12:40 PM
So a longer sparge at a lower temperature makes the beer more fermentable?
No, rather a lower mash temp for longer
Title: Re: fermentability question
Post by: Kirk on June 11, 2011, 09:01:57 PM
Yeah, because of the stuck sparges and all, it sounds like you really didn't mash at 152 for an hour.  At 152 for an hour, like you I would expect the FG to be a little higher.  Try some rice hulls next time, if you haven't tried them before.  They really help, and seem to improve efficiency also.
Title: Re: fermentability question
Post by: gymrat on June 12, 2011, 12:19:32 AM
I had stuck sparges but not stuck mashes. My mash was, in fact, 1 hour at 152 degrees.
Title: Re: fermentability question
Post by: Hokerer on June 12, 2011, 02:10:09 AM
I had stuck sparges but not stuck mashes. My mash was, in fact, 1 hour at 152 degrees.

What they're saying is that, unless you did a true mashout to denature the enzymes (and just adding 170F sparge water doesn't accomplish that), then your mash was still mashing the entire time you were sparging.  So your total mash time was the original one hour plus however long it took to complete your sparge.
Title: Re: fermentability question
Post by: gymrat on June 12, 2011, 03:40:16 AM
Ah thank-you for clearing that up. Once again I have learned something new.
Title: Re: fermentability question
Post by: gymrat on June 12, 2011, 02:41:42 PM
After a week in the bottle I sampled some of this beer after work last night. It is freaking incredible. After all the problems I had with it I was just sure I was going to end up dumping it.
Title: Re: fermentability question
Post by: dbeechum on June 12, 2011, 04:30:11 PM
That's the way it works. It seems like so often when you make all the stupid mistakes, suffer all the issues, the world steps up and delivers a great result.

Of course the irony is: how the hell do you duplicate it? :)
Title: Re: fermentability question
Post by: gymrat on June 12, 2011, 07:19:27 PM
EXACTLY!

This was also the batch where my wort chiller broke when it was 90 degrees. I had to let it air cool, I didn't want it to sit too long before pitching my yeast so I pitched at 77 degrees. Then the fermentation was so hot it didn't drop below 75 for 2 days in a room that was 68 degrees ambient temp.

I know I can't duplicate any of that.
Title: Re: fermentability question
Post by: jeffy on June 12, 2011, 07:38:19 PM
Speaking of throw-away brews, I racked the ill-fated IPA yesterday.  This is the batch that I wasted several hours trying to chill the wort with huge hop cones clogging everything and finally gave up and poured the whole thing, hops, break an all into an unsanitized open European keg that would fit into my fridge then sprinkled 2 packs of US-05 on it.  Surprisingly it tastes very good going into a secondary for dry-hopping.
Sometimes the mistakes taste better than the plans.