After a 20 year hiatus and about a dozen extract brews since jumping back into brewing after Alabama voted down prohibition May of 2013, I am fairly new to all grain with only half a dozen brews under my belt. I am a self confessed Denny’s Batch Sparge disciple because it got me into all grain with minimal cost over my extract set up while getting respectable results. I normally buy kitted recipes from online home brew suppliers and each comes with a recipe. I’ve noticed that nearly all recipes have different single infusion mash temps ranging from 151F to 154F. I’ve read on a couple different forums including this one that 148F to 150 should be used. So why the difference in recommended mash temps not only from the forum members but between the recipes?
The mash temp is one of the variables that will affect the relative fermentability of the resulting wort.
The two enzymes responsible for breaking down starch into sugar are alpha and beta amylase. Alpha amylase works best at temps between ~150-160 (ish) and creates a minimally fermentable wort. Beta amylase works best at temps in between 140-155 (ish) and creates a more fermentable wort.
so by mashing at 148 you maximize the beta amylase activity and therefore, in theory maximize the fermentability of the wort. a mash temp of say 154ish should produce a moderatly fermentable wort and a really high mash temp like 162 creates a minimally fermentable wort.
Less fermentable worts will produce a thicker mouthfeel and body with more residual sugars and more fermentable worts produce a more ‘digestable’ beer with a lower final gravity, and a lighter mouthfeel with less body.
generally speaking I mash at 148 for big belgians, big barley wines that I want to finish pretty dry, and the like. I mash at 155ish for everything of moderate gravity that shouldn’t be bone dry and 162 for small beers that I want to leave with a relatively large amount of body.
I agree with Mort’s temp recommendations. In general, a couple of degrees isn’t gonna make a noticeable difference.
Yup, I can tell between 148 and 158, but the difference between 152 and 156, not so much.
I used to always mash around 152, but the last year I’ve been mashing (especially lower gravity beers) @ 155-156 and I notice a difference in the body. I’ve found this has helped 4.5-5.5% beers not taste so thin.
+1 to this. I use 153F for 80% of my beers, but like it has been said, I don’t see much of a difference between 151-156ish. My session beers get mashed at 162, and beers I want super dry get mashed around 145-148.
+1 to all said above. A difference of a degree or two is unlikely to be noticeable at all. Like many I use some broad guidelines : 158 -162 F for low OG/session beers of ~ 1.040 OG and under.
152 -156 F for most beer styles of average OG - to give good body/mouthfeel
149 -151F for styles where I want a lighter body/drinkability
148F - most high gravity styles (barleywine, RIS, big Belgians, also Saison). There is
enough residual sugar in a beer this big to leave plenty of body and reach a
more drinkable FG.
Also, mash temps sub-150F get a 90 minute mash to assure good conversion.
I sure appreciate all the information and quick reply! This gives me a lot to think about.