Does anyone else do this? About every 4th or 5th beer I brew I’ll incorporate this technique when I don’t have a 4-5 hour window to brew. I’ll mash in just before going to bed, insulate the kettle (I BIAB) as best I can, then finish the brewing process in the AM. Depending on the season I find that the mash drops 30-40F overnight. My mash efficiencies are generally 5% higher using this method and I haven’t had any ill effects from this. I don’t have the equipment (or enough desire) to do an experiment testing the results of an overnight mash on beer taste compared to a traditional mash.
I wonder if since the temp is dropping from the low 150F’s to 115F or so if there is any “reverse step mash” effect going on?? Just curious what others think as I have extra time on my hands these days thanks to Covid-19
Positive: efficiency
Depends: extremely high attenuation, positive for some beers, negative for others
Negative: if proteases did not denature completely, they will degrade most proteins and FAN will be higher than needed. Hot side aereation is maximized (many question whether this is real)
I’ve never done it but I’ve read about folks who have. Like Lupulus said I imagine there’s a pro/con balance.
I agree that the unpredictability of the efficiency and attenuation have produced beers with much different gravities than I planned
Thanks for the link. I’m pretty sure that’s what gave me the idea to even try this method for myself, just didn’t remember!
I have overnight mashed a few times before. On one particular batch I actually put the MT (mash at 150 for an hour) in a 170 degree oven overnight (stainless steel MT). It turned out really, really good. It had a very complex malt depth.
I’ve never done it. When I’m pinched for time, I’ll mash & collect all of my wort on one day, heat the wort up a bit to pasteurize, then let that sit overnight. My guess is that this mitigates changes in fermentability of the wort.
I’m going to try this. I have a sous vide, so I’ll use that to try and retain some heat. Now I have a reason to leave work early on a Friday.