Sense Check - 70c Mash

[WonkyDonkey]

I'm hoping to get a brew on tomorrow that has a low(ish) target OG of 1041, 3.8% ABV.

After tinkering around in Brewfather I've gone for a mash temp of 70c for 90min in the hope that the beer will not dry out and finish around 1012. The grainbill includes a high amount of both flaked and malted oats, in the range of 25%.

Firstly, if I mash at 70c do I risk potentially not extracting all of the available sugars from the grain? Given the amount of oats, is there a risk of any off-flavours being produced further down the line at these temperatures?

I usually mash in the 65-68 range for a variety of styles, hence my hesitance when going out of my comfort zone

 

[peebee]

70C is fine. The enzymes "burn-out" a bit quicker (especially beta-amylase that breaks dextrins down to simple sugars) but they'll keep going long enough. I mash low-alcohol beers (<1%) at 74C, including high-ish proportions of oat malt (last brew had 16-17%).

I'll probably push mashing up to 75-76C next time because lack of attention caused my last low-alcohol beer to start mashing at 70C (it wasn't "low-alcohol" by the time it finished fermenting!).

 

[WonkyDonkey]

70C is fine. The enzymes "burn-out" a bit quicker (especially beta-amylase that breaks dextrins down to simple sugars) but they'll keep going long enough. I mash low-alcohol beers (<1%) at 74C, including high-ish proportions of oat malt (last brew had 16-17%).

I'll probably push mashing up to 75-76C next time because lack of attention caused my last low-alcohol beer to start mashing at 70C (it wasn't "low-alcohol" by the time it finished fermenting!).

Thanks for the vote of confidence. Is a 90min mash about right or do you think that I'd get the same efficiency if I went shorter at 60min or 75min?

 

[user 18729]

I’ve mashed at about 80 degrees before by mistake (dodgy thermometer) and whilst my efficiency was low the beer was fantastic- huge body and mouthfeel. 70-75 is a good range for English style beers where you want to add body and leave the FG a little high

 

[peebee]

Thanks for the vote of confidence. Is a 90min mash about right or do you think that I'd get the same efficiency if I went shorter at 60min or 75min?

I only mash for 30 minutes, but what I'm doing is a bit "odd".

I'd say 60 minutes is quite long enough (some main core recipes will do this at 66-67C). It's bound to carry some "suck-it-and-see". There is (was?) a commercial UK beer mashed at 74C (don't remember its name now).

 

[WonkyDonkey]

I only mash for 30 minutes, but what I'm doing is a bit "odd".

I'd say 60 minutes is quite long enough (some main core recipes will do this at 66-67C). It's bound to carry some "suck-it-and-see". There is (was?) a commercial UK beer mashed at 74C (don't remember its name now).

Thanks again, think I'll go at 70c and take readings from 45min onwards to see how conversion is going

 

[Zephyr259]

60 mins at 70c should be fine, I've done similar mashes before when wanting a higher FG. The mash runs faster at hotter temps, I don't really ever go past an hour but if I did it would be when I'm down at 63-64c.

There's no reason your efficiency would suffer from a high mash as you'll still convert the available starch to sugars, there will just be a greater percentage of unfermentable sugars compared to a lower temperature mash.

What are you making?

 

[WonkyDonkey]

60 mins at 70c should be fine, I've done similar mashes before when wanting a higher FG. The mash runs faster at hotter temps, I don't really ever go past an hour but if I did it would be when I'm down at 63-64c.

There's no reason your efficiency would suffer from a high mash as you'll still convert the available starch to sugars, there will just be a greater percentage of unfermentable sugars compared to a lower temperature mash.

What are you making?

Thanks. I'm brewing a clone of Sonoma by Track, GF's favourite session beer. I've brewed it once before, only my 2nd ever brew, and it came out really well but as I was in my brewing infancy I just let it ride and it finished low at 1007 on a 66c mash. A year on and with a few tweaks I'm hoping for an improvement on my first stab and more body to it

 

[Zephyr259]

Thanks. I'm brewing a clone of Sonoma by Track, GF's favourite session beer. I've brewed it once before, only my 2nd ever brew, and it came out really well but as I was in my brewing infancy I just let it ride and it finished low at 1007 on a 66c mash. A year on and with a few tweaks I'm hoping for an improvement on my first stab and more body to it

Cool, I'm not familiar with that beer but sounds good. What yeast are you using?

 

[WonkyDonkey]

Cool, I'm not familiar with that beer but sounds good. What yeast are you using?

For something that is 3.8% it drinks a lot bigger, highly recommend it.
This time I'm going with the Lallemand Verdant yeast, hoping to get some nice esters come through