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Message |
   
Ken Anderson
Senior Member Username: Ken75
Post Number: 1953 Registered: 11-2002 Posted From: 76.189.235.103
| | Posted on Sunday, January 08, 2012 - 09:22 pm: |
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I am wondering just how pronounced the effect of different mash temperatures is. I recently brewed two identical grain bills (though different hops), but with cold grains and sloppy Kentucky windage, the second batch mashed at 147 whereas the first batch mashed at 154. I liked the 154 batch better. More fullness to it, which would be expected, but it also had more flavor. The 147 beer, save for the 6+ percent alcohol, is as close to a NAIL as I've come, and that's not what I'm after. So is the mash temperature variable indeed a heavy-hitter in determining a beer's final outcome? It's hard to believe seven degrees could make that much of a difference, but maybe so. Oh, the grains were 6-row and malted wheat. No intentional unfermentables at all. 154 degree mash: 1.054 -> 1.008 147 degree mash: 1.054 -> 1.005 (Message edited by Ken75 on January 08, 2012) |
   
Bill Pierce
Moderator Username: Billpierce
Post Number: 13496 Registered: 01-2002 Posted From: 24.150.49.181
| | Posted on Sunday, January 08, 2012 - 10:29 pm: |
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In a word, yes, mash temperature is the "heavy hitter" in determining fermentability. Take a look at this post from Steve Jones: http://hbd.org/discus/messages/40327/42878.html?1189799053 Or in graphical terms: http://hbd.org/discus/messages/26895/33084.gif |
   
Ken Anderson
Senior Member Username: Ken75
Post Number: 1954 Registered: 11-2002 Posted From: 76.189.235.103
| | Posted on Monday, January 09, 2012 - 07:38 pm: |
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I have that data in a Word document from several years ago. It is supposed to be from "Malting and Brewing Science, vol 1, D.E.Briggs, J.S.Hough, R.Stevens, T.W.Young, Chaman and Hall, 1981". |
   
Greg Brewer
Intermediate Member Username: Greg_r
Post Number: 334 Registered: 03-2005 Posted From: 64.124.83.190
| | Posted on Monday, January 09, 2012 - 07:46 pm: |
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You are enjoying some strong attenuation at 85% and 91%! Yeast health is obviously not an issue for you. How confident are you in the accuracy of your gravity readings? My hydrometer has +-2 pts. precision, which suggests if I recorded your same data points, the attenuation could be the same. Of course I kid myself and treat my readings as 100% accurate. Regardless, you preferred the hotter mashed beer, which tells you a lot. |
   
Bierview
Senior Member Username: Bierview
Post Number: 1083 Registered: 03-2003 Posted From: 68.197.194.159
| | Posted on Tuesday, January 10, 2012 - 10:25 pm: |
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Also makes one think about the accuracy of your thermometer. I recently calibrated mine. It was 2 degrees cool. |
   
Steve Ruch
Intermediate Member Username: Rookie
Post Number: 315 Registered: 03-2003 Posted From: 66.96.79.211
| | Posted on Wednesday, January 11, 2012 - 12:33 am: |
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How about mash length? Two batches ago I had to run to the store and the mash went way longer than usual. I ended up at 1.007 instead of the 1.012 I expected. |
   
Bill Pierce
Moderator Username: Billpierce
Post Number: 13499 Registered: 01-2002 Posted From: 24.150.9.127
| | Posted on Wednesday, January 11, 2012 - 12:42 am: |
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Mash length is less of a factor than temperature or thickness, but in general, you are correct, Steve, that longer mashes result in more fermentable beer. However, I would be skeptical of even a doubling of the length of time being of and by itself the cause of a decrease in F.G. of 5 points. When I worked at a brewpub in Utah, where the alcohol content of the beer was limited to 4 percent ABV, the watchwords were "hot, thick and quick." This method, along with a portion of Carapils malt in the grist, did help to increase the body of lower gravity beers. (Message edited by BillPierce on January 11, 2012) |
   
Dan Listermann
Senior Member Username: Listermann
Post Number: 7899 Registered: 03-2004 Posted From: 72.49.60.83
| | Posted on Wednesday, January 11, 2012 - 01:52 pm: |
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I used to mash 60 minutes and a lot of beers were finishing in the upper teens. When I added 30 minutes, they got into the lower teens. My standard is 90 minutes. |
   
Denny Conn
Senior Member Username: Denny
Post Number: 7652 Registered: 01-2001 Posted From: 208.85.238.144
| | Posted on Wednesday, January 11, 2012 - 03:48 pm: |
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Same here, Dan. |
   
mikel
Intermediate Member Username: Mikel
Post Number: 419 Registered: 02-2001 Posted From: 166.181.3.177
| | Posted on Wednesday, January 11, 2012 - 05:53 pm: |
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I also do a 90 minute mash. I had higher final gravities, high teens, when i did a 60 minute. Now I get into the low teens and it seems I have more control over the body of the beer now by mashing hotter or cooler but still for 90 minutes regardless. When I did 60 minute mashes I almost always mashed in the low 150's trying to get a lower final gravity. |
   
Ken Anderson
Senior Member Username: Ken75
Post Number: 1955 Registered: 11-2002 Posted From: 76.189.235.103
| | Posted on Wednesday, January 11, 2012 - 06:06 pm: |
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I use one of those $35 refractometers exclusively; they are so easy to use. As far as accuracy, tap water always shows zero, for what that's worth. My thermometer is a Baxter digital probe type. It claims +/- .2 F, which is pretty good. Although there's not enough data here to be reliable, I think it's interesting that I hit identical starting gravities with these two beers, and yet the fermentability of the sugars was apparently not identical. I guess refractometers and hydrometers won't tell us the type of sugars they are measuring. |
   
Bill Pierce
Moderator Username: Billpierce
Post Number: 13501 Registered: 01-2002 Posted From: 24.150.9.127
| | Posted on Wednesday, January 11, 2012 - 07:46 pm: |
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You're correct Ken. Karl Balling discovered in the 1840s that the data he collected using sucrose solutions was essentially the same as that of wort. So the original gravity is the same, but the fermentability can be rather different depending on the composition of the specific sugars. |
   
Steve Ruch
Intermediate Member Username: Rookie
Post Number: 317 Registered: 03-2003 Posted From: 66.96.79.211
| | Posted on Thursday, January 12, 2012 - 12:36 am: |
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I took a gravity reading of the most recent brew I did with my normal length mash and it ended at 1.012 just like I expected. |