Question regarding Mash Temperatures

[RukusDM]

I'm a bit confused about Mash Temperatures. I've read in several books that typical Mash temperatures are between 150 and 160 degrees.

I've read that the higher temperature that you use to mash, you end up with more un-fermentable sugars.

I have Beersmith, and it doesn't adjust FG depending on what Mash temperature is used unless I'm doing something wrong.

How does one know what you can expect for a FG then? My latest brews have been around 150 and 152. They were a Light Honey Ale and a Light American Lager. Brewsmith predicted pretty well what I would end up at.

I have a couple other beers planned that used mash temperatures around 155 to 157. How can I predict what FG they will end up at?

 

[the_bird]

FG is one of the trickiest things to project accurately, and BeerSmith - for all its strengths as a program, doesn't really even try. My understanding is that the BeerSmith calc is simply derived based on your projected overall attenuation rate. It will not adjust automatically for higher mash temps, or even if you do something like add (100% fermentable) table sugar. It won't adjust for the different expected attenuation from various yeasts. Just one thing it doesn't do.

As you get more experience, you may want to adjust the attenuation assumption yourself, by hand.

 

[RukusDM]

FG is one of the trickiest things to project accurately, and BeerSmith - for all its strengths as a program, doesn't really even try. My understanding is that the BeerSmith calc is simply derived based on your projected overall attenuation rate. It will not adjust automatically for higher mash temps, or even if you do something like add (100% fermentable) table sugar. It won't adjust for the different expected attenuation from various yeasts. Just one thing it doesn't do.

As you get more experience, you may want to adjust the attenuation assumption yourself, by hand.

Thanks for that. I think its time for a experiment. I have a bunch of leftover grain. Maybe I'll make 2 1-Gallon batches with the same grains. One Mash at 150, and the other at 155. Boil both with same volumes and add the same yeast to both and see what happens. Maybe a 3rd at 160.

Might be interesting to see what happens. I'll use use 2-row or pilsner malt as that is what I happen to have left over.

In fact, I'm going down to the basement to do that now.

 

[RukusDM]

Initial Results from different mash temperatures. I did 2 Mashes with the same ingredients and the same yeast. Each 1 Gallon Final. The Mash was done on 1-1-2011. The Mashes were light on Grains but that is what I had on hand. Not sure if Higher OG's would show different results.

Ingredients Amount Item Type % or IBU
1 lbs 12.0 oz Pale Malt (2 Row) US (2.0 SRM) Grain 100.00 %
0.50 oz Saaz [4.00 %] (45 min) Hops 26.1 IBU

150 Degree Mash -
OG - 1.039
FG - 1.010
ABV 3.9 %

158 Degree Mash -
OG - 1.040
FG - 1.014
ABV 3.38 %

I'll check again tomorrow to see if the FG changes. They both appear to be done.

Edit: Typo on FG

 

[RukusDM]

I'll have to try this with larger volumes and different grain bill to see if the results are proportional.

I had to keep a close eye on the Mash temperatures as with such a small volume, the temperatures would drop much faster than with my normal 6 gallon batches. I had to add heat several times.

 

[RukusDM]

FG for the 158 Deg Mash was actually 1.016. I had a bit of foam on the top of the hydrometer sample. Once it cleared I read 1.016

 

[indigi]

When you get into trying to predict an FG dead-on, there's a ton of variables and not enough accurate information to get it right every time. Aside from mash temperature, programs don't account at all for the amount of crystal malts/unfermentable sugars (seriously, try putting in an all-maltodextrin grain bill in some calculators and you'll still see 70* attenuation), mash thickness, mash time, mash steps, etc. They all can affect the fermentability of your extract but there's just not enough information out there to calculate it. Most of the programs I've seen do a really good job of getting you in the ballpark, though.

 

[RukusDM]

IC.....thanks

 

[dcp27]

FYI, Kaiser has done a bunch of mash vs fermentablility experiments if you want to cheat on the results: http://braukaiser.com/wiki/index.ph...ity_and_efficiency_in_single_infusion_mashing

 

[RukusDM]

FYI, Kaiser has done a bunch of mash vs fermentablility experiments if you want to cheat on the results: http://braukaiser.com/wiki/index.php/Effects_of_mash_parameters_on_fermentability_and_efficiency_in_single_infusion_mashing

oohhh, that would save me some time. Now I'll just have to drink the low ABV gallon beers I've made. Maybe the daughter or the wife will like the light's.

Thanks