Overnight or Long Step Mash and effects on body

[ihavenonickname]

I'd like to try out overnight mashing with multiple steps. And I'm having a hard to wrapping my head around how this will affect the body and finishing gravity of my beer.

My plan is to mash in and follow this program:
146F for 120 minutes
156F for 120 minutes
161F for 30 minutes
172F for 4 hours... or less.

This will allow me to wake up, lift the basket, sparge and boil

My questions:
Would this lead to an highly attenuative wort?
Would it lead to a full bodied wort?
If I wanted it to lean more dry/alttenuative (for a WCIPA) what adjustments should I make?
If I wanted to make it fuller bodied (for a NEIPA) what adjustments should I make?
Does a step in the 158-160 build dextrins and body the longer it goes?
Any other recommendations for mashing over night but still having some control over body?

This chart is a helpful point of reference

 

[AlexKay]

I think all of your saccharification will be done (well) within those first two hours, and all of the other rests will just be for extracting things you don't want (e.g., tannins) from the grain.

Edit: sorry, to answer the question, this will be an attenuative wort, because you're mostly letting beta amylase go to town producing maltose.

 

[ihavenonickname]

So… is there a way to mash long (at whatever steps) and produce a full bodied beer? Beta for thirty minutes and then hours at the other steps?

 

[VikeMan]

IMO, "overnight mash" and "full bodied" are incompatible concepts, no matter the rest temperatures/lengths.

 

[SanPancho]

i assume your overarching goal is to go overnight, yes?

wait right until you hit the sack to mash in. go hot, upper end of alpha range. and then just let it ride all night long without any additional heat. just insulation if you got it. wrap it with a blanket. its the best you can do given the conflicting forces here. ive had some low-to-mid body stuff come out fine that way. so hopefully by starting higher you'll retain more body.

otherwise buy some maltodextrin and fix it in the kettle.

 

[tracer bullet]

Low temp + long time will basically net you an attenuative wort and a thinner body. Any steps after that might be a waste of time with no appreciable difference.

For body you'll want the opposite - higher temp, shorter times.

Also keeping in mind that as homebrewers we tend to enjoy the details and if you had a couple beers side by side where the only difference was the mash time and temp details... within reason you may not even tell the difference.

 

[dmtaylor]

I've written what follows without reading anyone else's responses (yet). I'll review theirs after my own.

Two things matter most of all, in my experience:

1) The temperature for the first 20-30 minutes of the mash, and​

​

2) The total amount of time spent within the Goldilocks zone of about 145 to 160 F.​

In your case:

• the first 20-30 minutes will be at 146 F. So okay, that's going to be a dry beer. And then
• the mash will stay in the Goldilocks zone for 4 hours. So okay, that's going to be a verrry dry beer.

So, expect very high attenuation, and very low FG, likely 1.002.

If you want fuller body, just mash at one temperature, say 155 F, for only 30 minutes and then mash out at 170 F. If you're mashing at night/morning, the mashout step only needs to take 10-15 minutes. Assuming you've got a robotic mash system, program it to begin at 5am or whatever. Otherwise just mash it yourself in person, it doesn't need to mash for long. Easy peasy.

The longer you mash at about 158-160 F, you'll still get higher fermentability, lower FG.

Consider not mashing all night long, but just doing a short mash of 45 minutes at whatever single temperature you think will work best. I've been mashing for just 40-45 minutes for over 150 batches for nearly 20 years. It works great. No need to overcomplicate things. There is very rarely any real use in dorking around with mash temperatures and step mashing. You can make great beer without making the mash profile complicated.

EDIT: IF you MUST mash overnight for many hours... then I'd recommend a high mash temperature, say 162 F or something in that neighborhood, to kill off the beta amylase and then let the alpha do most of the work. It will still make great beer, without being terribly dry. I haven't played around much in the 160s so I might be off by a degree or two. Play around with the exact temperature over many batches until you get what you like.

 

[jerrylotto]

Before you even get to starch conversion, there are lower temperature steps to consider:

Acid Rest - ca 100F where phytase and beta-glucanase start o break down phytin to lower the pH and glucan to make the grain less gummy.

Protein Rest - 125F up to 135F highly modified grains don't benefit much from this but adjuncts have proteolytic enzymes that break down proteins in this step.

The starch conversion steps you already have planned are all about optimizing beta- and alpha-amylase activity. As already mentioned, this is all about maximizing yield to produce a lower body and thinner mouthfeel.

If you want to extend a time, I would focus on the lower temperature phases - not "sparge" temperatures where all of the useful enzymes denature unless you want to decoct which is a whole different conversation.

 

[VikeMan]

I would avoid a protein rest, unless you are using an under-modified malt. With almost all modern malts, it has effectively already been accomplished during the malting process. Adding a protein rest will cause proteins to breaks down further, likely harming foam retention and body.

For the same reason, I would avoid any lengthy acid rests that are near the protein rest range.

 

[jerrylotto]

I would avoid any lengthy acid rests that are near the protein rest range.

Right - I was suggesting the OP wants to mash overnight, an extended low temp acid rest is the way to go - 95F - 100F (below the activation temps of proteolytic enzymes) then heat directly to 140F in am and step through to 162F over an hour or so.

 

[VikeMan]

Right - I was suggesting the OP wants to mash overnight, an extended low temp acid rest is the way to go - 95F - 100F (below the activation temps of proteolytic enzymes) then heat directly to 140F in am and step through to 162F over an hour or so.

But, there's no such thing (within mash temp range) as a low temperature threshold "on/off switch" for proteases. Like any enzymes, they are active (though less so) oustide of their typical published "optimum" ranges. So, we take a less active enzyme and let it be "less active" for a much longer time (overnight). Where is the total protease activity going to land?

There are lots of protease activity curves to look at out in google-land. They vary, based on the exact protease(s) tested and test conditions, but what they all have in common are bell-curve-like shapes over wide ranges, i.e. no brick walls on the low temperature side.

 

[balrog]

Consider not mashing all night long, but just doing a short mash of 45 minutes at whatever single temperature you think will work best.

Assuming you've got a robotic mash system, program it to begin at 5am or whatever.

This.

 

[demolition]

Not sure it was mentioned, but there’s a page about this on brulosophy. Note, a full wort, all night mash might give an ok result all by itself, because should an all night mash does create a more fermentable wort in your case, then a characteristic of alcohol is that it gives body and perceived sweetness to drinks, but it might be stronger %. Thus the taste effects are in line with what you’re looking for from the unfermentable sugars?

Anyway, I’m thinking aloud here, so this might work - or it might not:

1. mash the just base grains overnight - this’ll give you a fermentable initial wort, full of lots of enzymes. Maybe mash in a little high, but suggest staying in the magic range.

2. Put your non-diastatic malts in a grain bag, in a pot of cool bottled or pre-boiled water at 3L / kg (thicker probably ok, if still ok to stir). Try to keep this cool, but not cold, for the whole time that the hot mash is happening.

3. Run off the hot mash and do whatever you plan to obtain a pre-boil wort - e.g. sparging and/or topping up, etc. Allow space in the boiler for the cold non-diastatic soup.

4. Raise the temp of the boiler, keeping an eye on the temperature.

5. When the temperature of the boiler reaches 67°C (or more - up to 72°C), lower in the grain bag and the steeping liquor. Hold the temperature for 30 mins.

This is the point at which the mass of enzymes released by the main mash should be able to act on the starches of the non diastatic grains. Thus it should be possible to obtain their textures and flavours as the recipe requires without having them.

My thought process is: dissolve the non-diastatic grains (Breiss research is interesting about this), then mash these grains warm, as a preliminary part of the boiling process.

6. After 30 mins of mini mashing, remove the bag, raise the temp to 100°C and continue with the recipe.

This process would definitely reduce the time required on mash-day. Boil-day would be longer than the boil part of an all-in-one day, because the wort would have cooled to, let’s say, 30°C overnight, meaning à longer time to reach boiling than it would if it were coming straight from the mash process. Plus, there’s 30 mins for the mini mash. If someone has a 2h time slot one day and a 4h one the next day, it might be a good process?? (Time estimates don’t account for firefighting and problem solving)

Just a thought - ready to be trounced on!

 

[stealthfixr]

Makes me curious about making a very dry style like a Brut IPA (where you want little to no body and a super low FG) using an overnight mash. Anyone ever tried that before?

 

[dmtaylor]

Makes me curious about making a very dry style like a Brut IPA (where you want little to no body and a super low FG) using an overnight mash. Anyone ever tried that before?

Yes, it works well for saison too.

 

[ihavenonickname]

Thanks for the replies... so nice creative ideas here. For background I do have experience doing overnight mashes (no heat, no pump and just let the temp drop overnight. And it works great, I got ~90% mash efficiency, no problems, and a fermentable wort. saison, kolsch, and wcipa. (even won a gold medal (43/50) with a kolsch this way)

I'm hoping for a way to take advantage of my brew system (brewtools) by letting some mash steps go overnight. There are anecdotes of people holding 152-154 for 8 hours and getting super clear wort, great effeciency, and totally normal fermentability. So I guess that's what I would try first. Thanks @dmtaylor for the suggestion of high temp, long steps. I could try that too: 8 hours at 160. Hopefully one of those works to build some body.

I'd like to think that a mid 150s' step, followed by an hour at 162 or so would really build up some dextrins and lead to a fuller body even of the FG is low... But this is just my wishful thinking.

The Braumeister community seems to have a lot of luck running overnight step mash programs - they keep it at room temp for the first 6 hours or so , then run up though the steps over 2 hours or so before they wake up. That sounds really cool to me. But I have fears and doubts about the room temp step and bringing the whole mass of grain and water up from 70F to 150F without being there to watch it and make sure it recirculates at least somewhat.

So still open to creative ideas if there are any others out there!

 

[doug293cz]

I'd like to think that a mid 150s' step, followed by an hour at 162 or so would really build up some dextrins and lead to a fuller body even of the FG is low... But this is just my wishful thinking.

Dextrins don't get "built" by any of the enzymes in a mash. Dextrins are the remnants of the branched portions of amylopectin, that neither alpha, nor beta amylase can hydrolyze (break down to smaller carbohydrate/sugar molecules.) There is an enzyme in barley malt that can hydrolyze the branched bonds in amylopectin, and that is "Limit Dextrinase." The level of dextrins in the final wort is determined by how much activity the limit dextrinase enzyme accomplished during the mash. The more limit dextrinase activity, the less dextrin in the final wort.

Limit dextrinase denatures at the same, or slightly lower, temperatures as beta amylase, so its activity peaks at or below the beta rest temperature range, and rapidly denatures above that temp range. So, a "beta rest" in a step mash will decrease the amount of dextrin in the final wort, allowing for increased wort fermentability. Once the dextrins are hydrolyzed, they cannot be reconstituted by a higher temperature mash step.

Brew on

 

[AlexKay]

If you’re not getting the body you want, consider working with the grist instead. Flaked barley, or any sort of oats or rye, are high in polysaccharides (beta glucans and arabinoxylans) that won’t be broken up in any meaningful way no matter how you mash.

 

[odie]

I mash about 10 hours, while away at work. I don't notice any "thinness" in my beers. But I would have to do a side by side comparison to be sure.

I mash in at ambient temps and let it rise to 150 (takes about 30 minutes) where is stays until I get home. Recirc pump the whole time.

I supposed I could kick the heat on, go shower, then mash in? Perhaps set the temps to 155-160 to try to retain "body"?

med/dark grains usually get tossed in right before mash out. So not the 10 hours for them.

 

[odie]

perhaps a little bit of lactose to help body? I don't think it will impact flavor.

 

[dmtaylor]

perhaps a little bit of lactose to help body? I don't think it will impact flavor.

I do this sometimes. In fact on my last batch, it attenuated way more than expected and ended up tasting thin. Added a few ounces of lactose, and now it's perfect.

 

[Kickass]

Assuming you've got a robotic mash system, program it to begin at 5am or whatever.

Im with Dmtaylor here. All of this seems extraneous with a programmable system. Program a standard mash to be completed when you wake up.

 

[ihavenonickname]

I mash about 10 hours, while away at work. I don't notice any "thinness" in my beers. But I would have to do a side by side comparison to be sure.

I mash in at ambient temps and let it rise to 150 (takes about 30 minutes) where is stays until I get home. Recirc pump the whole time.

I supposed I could kick the heat on, go shower, then mash in? Perhaps set the temps to 155-160 to try to retain "body"?

med/dark grains usually get tossed in right before mash out. So not the 10 hours for them.

Im with Dmtaylor here. All of this seems extraneous with a programmable system. Program a standard mash to be completed when you wake up.

Yeah this could be a good option. The problem I see with mashing in at room temp is during the ramp up you are basically running through all the low temp mash steps - that much time in beta range would surely lead to a very dry beer.

Dextrins don't get "built" by any of the enzymes in a mash. Dextrins are the remnants of the branched portions of amylopectin, that neither alpha, nor beta amylase can hydrolyze (break down to smaller carbohydrate/sugar molecules.) There is an enzyme in barley malt that can hydrolyze the branched bonds in amylopectin, and that is "Limit Dextrinase." The level of dextrins in the final wort is determined by how much activity the limit dextrinase enzyme accomplished during the mash. The more limit dextrinase activity, the less dextrin in the final wort.

Limit dextrinase denatures at the same, or slightly lower, temperatures as beta amylase, so its activity peaks at or below the beta rest temperature range, and rapidly denatures above that temp range. So, a "beta rest" in a step mash will decrease the amount of dextrin in the final wort, allowing for increased wort fermentability. Once the dextrins are hydrolyzed, they cannot be reconstituted by a higher temperature mash step.

Brew on

Thanks for the correction and clarifying. I've read some homebrewers swear by a step at 160-162 for added foam retention and body. But based on what I'm learning that doesn't seemly very plausible.

 

[VikeMan]

Thanks for the correction and clarifying. I've read some homebrewers swear by a step at 160-162 for added foam retention and body. But based on what I'm learning that doesn't seemly very plausible.

Try not to confuse Proteins with Carbohydrates. A Glycoprotein Rest at about 162-163-ish can help get glycoproteins (which are foam positive) into solution/suspension. But it doesn't build dextrins (which are carbohydrates).

 

[Kickass]

The problem I see with mashing in at room temp is during the ramp up you are basically running through all the low temp mash steps - that much time in beta range would surely lead to a very dry beer.

That’s a good point. I failed to consider that part.

As a new dad with a 6 month old baby causing chaos at our house, I’ve recently started overnight mashing. I have three unfinished batches going now so no data for you. Sorry. I’ve targeted 154 for a dry beer and 157 for a little more body and residual sugar. I’ll report back when I package in the next week or so.

 

[tracer bullet]

As a new dad with a 6 month old baby causing chaos at our house

Been there too, and not so long ago. An idea of what I did, and still do, if it helps:

Prep everything the night or even through the day before
Have mash water come to temp while we're all asleep (kick on like 4AM or so)
Wake up, mash in, walk away for a while
Go get the family up and fed, inhale some coffee, etc.
Come back in an hour to actually begin brewing, spend maybe 2 hours to get it up to a boil, boiled, and cooled back down
Once it's cooled, again walk away for a while (not forever, but a while, and do family things)
Move into fermenter and pitch yeast
Can walk away again
Finish cleaning up and putting stuff away

Other than that single 2 hour stretch, I can walk away for a while and then come back to pickup where I left off.

 

[odie]

I do this sometimes. In fact on my last batch, it attenuated way more than expected and ended up tasting thin. Added a few ounces of lactose, and now it's perfect.

define a "few ounces". I'd hate to try it and ruin it.

 

[Bassman2003]

I think it is good to define some homebrewing terms a little differently from my experiences:

1) Creating a "Dry" beer. Attenuation is often associated with dryness, but I do not think this is a direct relation of a term. Well attenuated beers are not always dry. Imho, that 'homebrew flavor' is often under-attenuation (as well as oxidation). When I think of attenuation, I see a well attenuated beer as being in the low 80's. This does not need to be dry or thin. I have had plenty of Belgian beers that are not thin but are plenty attenuated. So imho, the goal for many beers should be good attenuation along with creating the taste and mouth feel etc... as desired.

2) Brewing beer is about stripping things away. We start with sugar water (wort) and take things away through the brewing process to end up with beer. What we decide to keep is our end product. So longer time mashing is more time for things to be stripped away. The challenge the OP has is extending the process but leaving a lot behind. Kind of difficult from this basic perspective.

Sometimes convenience is not the best approach for the final product. Maybe just using the overnight timer to warm the strike water so you can jump right in would be the best method?

 

[dmtaylor]

define a "few ounces". I'd hate to try it and ruin it.

I've said this dozens of times in the past and I'll say it again. Assuming a 5-gallon batch:

1/2 pound of lactose adds just a little something, barely detectable.
1 pound is a LOT.
When in doubt, use 3/4 pound.

Sometimes I say "a few ounces" because I typically only brew 1-2 gallons at a time. So I think I added like 2-3 ounces and that was enough, for ME.

 

[VikeMan]

I've said this dozens of times in the past and I'll say it again. Assuming a 5-gallon batch:

1/2 pound of lactose adds just a little something, barely detectable.
1 pound is a LOT.
When in doubt, use 3/4 pound.

Sometimes I say "a few ounces" because I typically only brew 1-2 gallons at a time. So I think I added like 2-3 ounces and that was enough, for ME.

Heh. I just added 2 lbs yesterday to a 5 gallon batch of "pumpkin pie" brown ale. Of course, it's intended as a "pastry" beer (a term that kind of annoys me because some of use were making these kinds of beers for years before millenials decided they had invented something new).

 

[dmtaylor]

Heh. I just added 2 lbs yesterday to a 5 gallon batch of "pumpkin pie" brown ale. Of course, it's intended as a "pastry" beer (a term that kind of annoys me because some of use were making these kinds of beers for years before millenials decided they had invented something new).

Enjoy your pastry. Hell... it might even be good, if you made it. Cheers.

 

[balrog]

Enjoy your pastry. Hell... it might even be good, if you made it. Cheers.

I will often try samples of many things but the current state of my tastes, and frankly the historical states of my tastes, have never found me wanting more than a sip of any of these (I'm sure wonderful) pastry stouts. But as I have said before, I also despise lima beans and love brussels sprouts. And dry Irish stouts.

 

[BPenny]

Early on in my brewing days, I also had a 6 month old and during that time I made several smaller batches of beer by mashing in at a variety of temps ranging anywhere from room temp to 130 F in a brew kettle that I would place in a 170-180 degree (F) oven overnight. 7-8 hours later the mash temp would usually be somewhere between 140-155 degrees. My main observations were:
1) I always ended up with a significantly higher sg than expected
2) My beers would always ferment out to around 1.000.
3) The body was somehwat thin, but not necessarily inappropriately so since I was making mostly saisons and mixed fermentation sours, plus the extra alcohol (and whatever else I may have extracted from the grains) seemed to contribute some body and perceived sweetness.
4) The primary negative effect was on the head retention. The beers would basically come out looking like barrel aged mixed culture beers with only a thin ring of foam, even if I only fermented them for a month. In agreement with what others have commented, I would assume that was from the extended protein rest more than a lengthy alpha/beta amylase rest. This is the biggest reason why I no longer use this method, but it worked ok for some styles.

 

[odie]

just mashed in this morning. doing a pumpkin ale.

This time I heated the mash water to 155 BEFORE mashing in. It will ride for 10 hours. Maybe this will give more body than mashing in at 80 and letting it step up to 150 for the same 10 hours.

Or will 10 hours mashing make it "dry" no matter what? Or maybe kick it up to a 160 mash in and hold it there for several hour?