Mash Temperature - how low is too low - Home Brew Forums
Register Now For Free!

Home Brew Forums > Home Brewing Beer > All Grain & Partial Mash Brewing > Mash Temperature - how low is too low

Reply
 
Thread Tools
Old 11-11-2009, 08:16 PM   #1
avshook
Recipes 
 
Mar 2009
Victoria, British Columbia
Posts: 17


I do a single step infusion mash and I usually hit a temperature of 152-156 and my beers end up a little sweet for my taste. So, I'm trying a mash at 148 today. How low can I go and still get full starch conversion? I know I have to mash longer at lower temperatures, but how low is too low for a single step infusion mash?
I'm doing a 10 lb batch, 9 lbs of 2 row, 1 lb of crystal.

 
Reply With Quote
Old 11-11-2009, 08:18 PM   #2
babalu87
Recipes 
 
Feb 2008
Middleborough, MA
Posts: 1,895
Liked 8 Times on 7 Posts


You can get conversion at 143 so RDWHAHB

148 will make a nice dry beer

 
Reply With Quote
Old 11-11-2009, 08:35 PM   #3
TexLaw
Here's Lookin' Atcha!
HBT_LIFETIMESUPPORTER.png
 
TexLaw's Avatar
Recipes 
 
Sep 2007
Houston, Texas
Posts: 3,670
Liked 28 Times on 26 Posts


148 is fine, but I wouldn't go any lower than that. I cannot be precise, off-hand, but getting much lower will markedly decrease alpha-amylase activity. That alpha-amylase is important, as it exposes more non-reducing ends for the beta-amylase to chew up into maltose. At the very least, you will slow your conversion down for no good reason.

If your beers are too sweet for you, you probably ought to look into changing your hop regimen more than your mash.


TL
__________________
Beer is good for anything from hot dogs to heartache.

Drinking Frog Brewery, est. 1993

 
Reply With Quote
Old 11-11-2009, 08:57 PM   #4
XXguy
 
XXguy's Avatar
Recipes 
 
Dec 2008
Southeastern PA
Posts: 1,118
Liked 16 Times on 15 Posts


Why not just cut back on the Crystal? Crystal adds sweetness, and a pound seems like quite a bit to me.

I'd rather mash at 152 with less crystal.

 
Reply With Quote
Old 11-11-2009, 09:16 PM   #5
z987k
 
z987k's Avatar
Recipes 
 
Feb 2007
Anchorage
Posts: 3,518
Liked 30 Times on 28 Posts


Quote:
Originally Posted by avshook View Post
I do a single step infusion mash and I usually hit a temperature of 152-156 and my beers end up a little sweet for my taste. So, I'm trying a mash at 148 today. How low can I go and still get full starch conversion? I know I have to mash longer at lower temperatures, but how low is too low for a single step infusion mash?
I'm doing a 10 lb batch, 9 lbs of 2 row, 1 lb of crystal.
Remember that unconverted starches are not sweet. They in fact have very little "taste". I can make a highly dextrinous wort that has no sweetness at all.
If you think you are not getting full conversion you need to take other steps.

I would do an iodine test to check for conversion if you are really worried about it.

However to you're question, how low can you go, you should be able to go as low as even 130, and if held long enough will convert, however this is highly inadvisable. Maximum fermentability is usually going to be in the 145 range where alpha, beta and limit dextrinase are all able to work (alpha being rather slow at this temperature).
Highest fermentable yield is usually in the 148-150 range.
You can also get "full" conversion at much higher temperatures. 158 will give you a fully converted wort(fast to), with low fermantability, so lowering the temperature does not increase conversion as long as you are within the accepted range for the amylase.
Obviously these should not be the only deciding factors when choosing a mash temperature.

Basically what I'm getting at, is your mash temperature has little to do with the sweetness of your beer.


 
Reply With Quote
Old 11-11-2009, 11:41 PM   #6
david_42
 
david_42's Avatar
Recipes 
 
Oct 2005
Oak Grove, Oregon, USA
Posts: 25,597
Liked 155 Times on 145 Posts


It isn't just a matter of conversion. The starches in barley don't gelatinize well below 148F. You can make up for that by longer mash times and some extra stirring.
__________________
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"

"I would like to die on Mars, just not on impact." Elon Musk

 
Reply With Quote
Old 11-12-2009, 12:32 AM   #7
kanzimonson
Recipes 
 
Aug 2009
Charlottesville, VA
Posts: 2,174
Liked 44 Times on 40 Posts


+1 to what z987k says. If you mash at higher temperatures, you produce unfermentable sugars. But even though we call these "sugars," most are not perceptible as sweet to the human tongue. If you mash at lower temperatures, it's true you'll produce simpler sugars, which are more easily consumed by yeast. BUT, yeast still have a fairly consistent range of attenuation levels. Once they reach these upper levels, their energy stores run low, and then they kick out. Consequently, you'll be left over with some of these simpler sugars you created during mashing, and your beer will be perceived as sweeter.

So I think that mashing at lower temps will give you the exact opposite effect you're looking for. Use less specialty grains in your beers and up the hop bitterness instead.

 
Reply With Quote
Old 02-07-2012, 04:48 PM   #8
Chu
Recipes 
 
Feb 2012
Richmond, VA
Posts: 2

So, I am trying to learn all-grain and following recipes, but my beers are coming out 'thin' without much body at all. I am concerned that I may not be maintaining a high enough mash temp. Is this likely a result of too cool a mash? Would mashing for longer times help if my mash temp was too low?

 
Reply With Quote
Old 02-07-2012, 06:57 PM   #9
Calichusetts
 
Calichusetts's Avatar
Recipes 
 
Nov 2011
Plymouth, MA
Posts: 3,015
Liked 500 Times on 300 Posts


Or you could just add honey to dry it out and increase the ABV...don't know if you like your beers light or heavy

 
Reply With Quote
Old 02-08-2012, 02:28 PM   #10
Junkster
Recipes 
 
Feb 2011
North Central, Ohio
Posts: 509
Liked 31 Times on 22 Posts


The OP doesn't mention terminal gravities or yeasts used - another variables to consider?

 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Effects of Mash Temperature PhilsBeard74 General Techniques 3 09-30-2009 11:12 PM
Mash Temperature Chub All Grain & Partial Mash Brewing 1 08-18-2009 07:03 AM
Help: Low Mash Temperature alfista All Grain & Partial Mash Brewing 6 12-20-2008 09:57 PM
Mash Temperature Never Got Over 160. What are the consequences? RoseburgBrewer All Grain & Partial Mash Brewing 1 09-14-2008 04:52 AM
Mash Temperature help ohiodad Recipes/Ingredients 3 01-19-2008 02:24 AM


Forum Jump