Why mash at 150 deg. F?

[SOB_OCDAVE]

Just wondering about the temp. gap between Alpha and Beta Amylase...

Alpha-amylase works best between 65-67 C or 149.0-152.6 F
Beta-amylase works best between 52-62 C or 125.6-143.6 F

Now, the gap between 62-65 C or 143.6-149.0 F is about a 5 degree F window where you might assume would get the maximum benefits from both alpha and beta amylase. So why do most brewing reference materials recommend 150 F for a fully modified malt using a single infused mash instead of say 146, 147, or 148?

I am a 8 year homebrewer with 6 years of all-grain experience. Just looking for some technical info on this process. Thanks for your replies.

 

[PintOfBitter]

I think Palmer tackles that question in How to Brew. maybe check www.howtobrew.com

 

[kanzimonson]

I have a guess: Those temperatures may be optimal for enzyme activity, but remember, our goal in mashing is not to maximally utilize enzymes, it's to create a certain sugar profile for our wort. Some beers are just plain better when they are mashed at higher temps and consequently end up with more dextrines and a higher FG.

 

[chefmike]

ask kai...

 

[jkarp]

Kinda hope kai sees this as well. It's an interesting question...

 

[SOB_OCDAVE]

I found this suggestion in an article about home distillation:

"The higher mash temperatures (65-70C)150-158 F will produce dextrinous (heavy bodied beers, lots of "mouth feel") in a shorter period, whereas lower mash temperatures (62-63C)143-145 F will produce more fermentable (more alcoholic) beer over a longer time period."

Has anyone ever mashed at 143-145 deg F?

 

[jackson_d]

sure i did a bad ass 10 gallon batch of Saison this summer. one 5 gallon primary with 3711 and one 5 gallon primary with 3724. i mashed the grain at 148 for 90 min. the beer turned out super dry and crisp. excellent compliment to the orange peel and ground corriander seed that went in the boil. and then just a hint of spice from the belgian and french yeast. i preferred the 3724 myslef, but it took almost 9 weeks to ferment out fully.

it finished at 1.007 FG

it was super dry but perfect for the style.

i right now have a milk stout in primary for its second week that we mashed at 156 for 60 min. i wanted that to be sweet and thick, so the higher mash temp and re hydrated yeast and it bubbled for almost 5 days.

longer mash times dry out the beer. lower mash temps also dry out the beer. higher mash temps give you a sweeter beer. its fun to alter a few degrees or a few mintues based on what you are brewing and see what you come out with. i personally dont worry quite so much about the science, i just happen to know what kind of results you get with longer times and higher or lower temps...

RDWHAHB!

 

[BigEd]

Just wondering about the temp. gap between Alpha and Beta Amylase...

Alpha-amylase works best between 65-67 C or 149.0-152.6 F
Beta-amylase works best between 52-62 C or 125.6-143.6 F

Now, the gap between 62-65 C or 143.6-149.0 F is about a 5 degree F window where you might assume would get the maximum benefits from both alpha and beta amylase. So why do most brewing reference materials recommend 150 F for a fully modified malt using a single infused mash instead of say 146, 147, or 148?

I am a 8 year homebrewer with 6 years of all-grain experience. Just looking for some technical info on this process. Thanks for your replies.

Because the mash temp range of 150/152F is a good general purpose, default temp that works well with many beers. It is the simple answer and most homebrewers and homebrew info is geared to the simple answer. Also with highly modified malts much of the actions which would take place in those lower temp mash steps have already happened in the malting process.

That is not to say you cannot do it or there would not be some possible benefits for certain malts and beer styles. Mega brewers like AB often use ramped infusion mashes which start at about 118F and slowly rise to the 150/152F range. Some German maltsters, like Weyermann, do recommend lower temp mash temps to be included in the schedule. You can certainly modify existing mash schedules or create your own to produce specific effects that you want to have in your beer. Reading some publications beyond the basic literature will give some insight into the topic. Noonan's"Brewing Lager Beer" is probably a good place to start.

 

[BigEd]

Has anyone ever mashed at 143-145 deg F?

Sure, but not for a beer brewed for drinking. Distiller's beers are mashed very low to maximize attenuation and alcohol potential. I'll mash certain styles, like an Altbier for instance, at 148F but I don't know offhand of any standard drinking beer that would go much lower than that.

 

[david_42]

Gelatinization of the starches in barley works best above 149F. You can mash lower than that, but it takes a long time and you'll have a very thin beer.

 

[mc_eric]

My understanding is that the beta amylase is still active at temps that favor alpha amylase activity, but it begins to denature slowly once it gets above ~145 F or so. The higher the temp, the faster it denatures. So, the Beta will be working on starches at the beginning of the mash, but by the end it will be mostly denatured, and the only enzyme working will be Alpha.

So, basically, if you mash below 149 F you get little or no alpha activity. As, david 42 said, it will result in an extremely thin beer w/ little malt flavor. When you mash at a particular temp, you are really just kind of setting a "timer" on beta activity:

Higher temps = shorter period of beta activity = sweeter, less fermentable beer.

 

[StAnthonyB]

Just wondering about the temp. gap between Alpha and Beta Amylase...

Alpha-amylase works best between 65-67 C or 149.0-152.6 F
Beta-amylase works best between 52-62 C or 125.6-143.6 F

Now, the gap between 62-65 C or 143.6-149.0 F is about a 5 degree F window where you might assume would get the maximum benefits from both alpha and beta amylase. So why do most brewing reference materials recommend 150 F for a fully modified malt using a single infused mash instead of say 146, 147, or 148?

I am a 8 year homebrewer with 6 years of all-grain experience. Just looking for some technical info on this process. Thanks for your replies.

When mashing at 149F versus 158F for 60 minutes the 149F extract is approx. 5% more fermentable. At 120 minutes the 149F extract is approx. 9% more fermentable. At 180 minutes the fermentability of the 149F extract is about 10% more fermentable than the 158F extract.

When mashing at 158F the maximum fermentability actually occurs at about the 45 minute mark. After the 30 minute mark the fermentability actually decreases slightly and holds.

The highest yield of fermentable extract occurs at 149F at about the 120 minute mark. The enzymes work slower at this temperature and it allows them to work more efficiently. Should still desire to extract sugars that are not quite as fermentable in order to retain body then perform a 162F to 167F mash out around the 90 to 100 minute mark.

Now, in many British styles 149F mash temperature will help achieve the low target gravities highlighted by the stylebook. Just remember when mashing at 158F the mash should be complete at about 30 minutes and at 149F the mash is complete in 2 hours, and at 140F the mash takes over 3 hours. If you want a brew that is much less fermentable mash at 162F and it will take no time before the ezymes wear out.

(I only know enough to be dangerous -- so be gentle on me)

Oh yeah.... Maximum yield also happens at about 4 liters per kilogram of grain, but at this ratio there is less soluble nitrogen, so go easier on less diatastically potent ingredients. White wheat malt has the highest diatastic power and soluble nitrogen content, so make about 3% of the grist a white wheat malt. Briess sells it. It is higher in protein than European wheats so go easy.