Save time on mash step

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landoa

WheatBeer
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Hello,

Just thinking about how to save time during the mash. Some folks do an overnight mash in a mash tun. I have a steel kettle and i'm sure i'd lose too much heat. If the temperature falls below 130F, there problems with bacteria which can be killed off during the boil, but may leave a persistent off taste.

My compromise would be to start the mash first thing in the morning around 8h00 and come back around 11h00 after morning errands. The normal 60-90 minute mash would be 3 hours. Maybe this will bump up efficiency a little but it would save time as I wouldn't be stuck at home.

I would do it with BIAB, which apparently requires more stirring more often during the mash. I figure the longer mash would make up for less stirring.

I lose around 5F / hour. So, if I started at 153F, i'd end up at around 138F.

Sounds doable?
 
If the temperature falls below 130F, there problems with bacteria which can be killed off during the boil, but may leave a persistent off taste.

Bacteria are not good at flying. Finish your mash, put the lid on, and walk away. There will be a few bacteria that get it but not many and they would then need to propagate which takes time. You will will be adding billions of yeast before the bacteria have a chance to get ahead and once the yeast get established the bacteria don't have a chance.
 
Extended mashes at lower temps typically yield a more fermentable wort. Make sure that's what you're after for your beer. ;)

I fully expect the same to happen in your case, starting at 153F and slowly dropping to 148 over an hour.
Then over the next hour conversion continues (mostly by Beta Amylase) but more and more slowly as the temps drop toward 143. Below 140F not much should happen, it's just waiting for you.

Don't worry about bacteria in that short time span. If left overnight (8-12 hours) you may get some souring, not sure.

Do you insulate your kettle to reduce heat loss? Brewers often forget about the bottom, it's a huge heat drain, as is the lid, uninsulated.
 
Thanks for all of your comments.

Now, how does this affect trying to hit the pre-boil target gravity?

A recipe will state the mash time. I assume, with a certain efficiency, this is the time required to hit the pre-boil gravity. But, isn't it reasonable to stop the mash before the recipe's mash time if the target OG is reached?
 
Now, how does this affect trying to hit the pre-boil target gravity?

A recipe will state the mash time. I assume, with a certain efficiency, this is the time required to hit the pre-boil gravity.
Extended mashes may convert a little more, that will result in a slightly higher OG and mash efficiency.

Realize, the bulk of starch conversion happens rather fast and most of the mash has already completed within the first 10-20 minutes.
How fast depends many factors, such as the mash system, thinness of mash and probably most importantly, fineness of crush. Smaller grain bits hydrate faster, more thoroughly, and collectively have a larger surface available.

It's diminishing returns after those first 20 minutes. Now Beta Amylase can still nibble on the ends and make your wort more fermentable when left for extended times, especially at lower temps.

But, isn't it reasonable to stop the mash before the recipe's mash time if the target OG is reached?
No, we want complete conversion, that's for mash efficiency.
But we target a certain mash temp to create a sugar profile we're after. Temperature is the main driver of that sugar profile (see graph below). So when the mash is done we stop the mash to retain that profile by performing a mashout by raising the temp to 168-170F which stops the conversion process by denaturing all (or most) of the enzymes.

Enzyme Activity in Mash.jpg
 
I mash all day. I mill and fill the kettle the night before. In the morning I turn the electric kettle on, set for 150', mash in at room temp, start recirc pump. About 5 min total time. Then after my shower/shave/sh*t, mash is approaching 150' and I leave for work.

I return about 10 hours later to a 150' recirculating mash and set 180' for mash out.

Has been working out well so far. Takes maybe 5 minutes or so in the morning. Never thought about the sugar profile.

I did once mash in at room temps at night and let it sit until the morning to start the kettle. I figured cold mash all night would not do anything and wanted to just "flip the switch" in the morning and run to work. It resulted in a rather pungent mash. Beer was drinkable but was not the desired flavor of the recipe.
 
i like that enzyme activity chart.

just so i got this straight, the mash out is the beginning of the boil, only the grains are still in the wort?

>>>> No, we want complete conversion, that's for mash efficiency.
complete conversion of starches to sugar? so when you get the complete conversion, you have hit the target OG?

if you are within 10 points (+/-) of the target OG, do you make adjustments during the batch to get it closer (adding DME, extending mash time, adding water)? or on the next batch (changing coarseness of grain mill or adding more grain than indicated in the bill)?
 
i like that enzyme activity chart.
It's a wonderful visual reference to the relationship between wort fermentability and mash temps. The more you study and understand it the more sense the variables that are involved make.

just so i got this straight, the mash out is the beginning of the boil, only the grains are still in the wort?
No, the mashout is done at the end of the mash, to lock in the sugar profile that corresponds with the chosen temp for the saccharification rest.
The saccharification rest is usually 60', but can be shorter or longer.

The mashout is performed by bringing the whole mash (grains and wort) to 168-170F (max!) and leaving it there for 10 minutes. That denatures pretty much all the enzymes. Starch conversion is arrested as well as any enzymatic activity that converts dextrins (chopped-up starches) into sugars (maltose, maltotriose, glucose, etc.).

After the mashout the liquid ("wort") is separated from the grains ("lautered and sparged"), leaving merely damp "spent grain" behind in the end, which can be used as animal feed, composted, or some used as an adjunct to bake bread or cookies from.

The claimed clear (or slightly hazy) wort then gets boiled with hops. Wort becomes "beer" when you pitch yeast.

I can highly recommend obtaining a copy of John Palmer's How to Brew, 4th Ed.
In a pinch, the How to Brew website hosts an old, first edition. It's free, and although a bit dated, the principles haven't changed.
 
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if you are within 10 points (+/-) of the target OG, do you make adjustments during the batch to get it closer (adding DME, extending mash time, adding water)? or on the next batch (changing coarseness of grain mill or adding more grain than indicated in the bill)?
You can add extract or water any time you see need for it. ;)
Add extract to the kettle (after the boil is done but before chilling) or add it to the fermenter (you may want to pasteurize it beforehand, for all security).

When the mash is done (e.g., saccharification rest, that's where the sugars are "formed") there's not much you can change. Keep notes, so next time you can adjust.

Coming up short in gravity happens to everyone, so make notes and, adjust for next time.
The whole trick is to arrive exactly at the recipe's OG (and volume) after the boil.

That involves a few variables, all depending on your equipment and techniques used, such as:
  1. complete conversion to maximize extracted sugars,
  2. in the composition/ratio the recipe is designed for,
  3. with good lautering and sparging to claim as much wort from the grist as possible,
  4. ending up with the correct volume AND gravity of your pre-boil wort.
Then after the boil, you should end up with:
  1. the exact volume of post-boil wort,
  2. at the recipe's intended gravity (that's your OG)
  3. and a bunch of other things, such as IBUs, amount of hop flavor, aroma, etc.
So...
You should try to aim for hitting that (really, not so) elusive OG (and volume) right on the nose.
After a few brews you should have honed in on that.

Your boil-off volume can only be determined during an actual boil on your equipment, You can start with an estimation of between 1/2 - 1 gallon boil-off per hour. And adjust accordingly on the next, and fine tune on the 3rd.

Here's a neat visualization for the mind:
Gravity and Volume are like a rubber band, the amount of sugar doesn't change (unless you spill it or leave some behind)
  • longer but skinnier ==> larger volume but lower gravity
  • shorter but thicker ==> smaller volume but higher gravity
If this all sounds a little like magic right now, after a few brews it will all make more sense.
As our homebrew mentor Charlie (Papazian) would say: RDWHAHB!
 
I'm surprised that there are more than a couple of people doing over-nite mashes. I'm so anal about mash temps, that letting my tun cool to room temperatures after several hours makes me cringe. I strive on consistency, just letting it fly....not me. But if it works for you, more power to ya!
 
I'm surprised that there are more than a couple of people doing over-nite mashes. I'm so anal about mash temps, that letting my tun cool to room temperatures after several hours makes me cringe. I strive on consistency, just letting it fly....not me. But if it works for you, more power to ya!

You may be overstressing and missing out on a lot of the fun of brewing. You may be attempting to keep a steady mash temp for the full hour of the mash while your conversion was done in 15 minutes (not guaranteed but often happens). I've read that the enzymes that do the conversion are quickly denatured at mash temp and while they didn't define "quickly", my experience is that it happens way quicker than most brewers realize. Once denatured there is no further activity so your wort doesn't become way more fermentable.
 
i like that enzyme activity chart.

just so i got this straight, the mash out is the beginning of the boil, only the grains are still in the wort?

>>>> No, we want complete conversion, that's for mash efficiency.
complete conversion of starches to sugar? so when you get the complete conversion, you have hit the target OG?

if you are within 10 points (+/-) of the target OG, do you make adjustments during the batch to get it closer (adding DME, extending mash time, adding water)? or on the next batch (changing coarseness of grain mill or adding more grain than indicated in the bill)?

Forget mash out. When you "need" mashout is when you are fly sparging and if you are doing BIAB you are not fly sparging.

If I were way short of my target OG I might add some DME but with my BIAB I normally overshoot the expected OG. I could add water but then I would be diluting the flavor so I just suffer with a little extra alcohol in my beer and try to reduce the amount of base malt in the next batch. If you are making a batch from a recipe that is expecting a 70% efficiency and come up short on the OG, you milling is at fault. Tighten up the mill gap. I expect no less than 90% any more.
 
Bacteria are not good at flying. Finish your mash, put the lid on, and walk away. There will be a few bacteria that get it but not many and they would then need to propagate which takes time. You will will be adding billions of yeast before the bacteria have a chance to get ahead and once the yeast get established the bacteria don't have a chance.
Did exactly that, created a sourmash over night, NOT A GOOD IDEA :D

I guess the culprit is the bag which does not get heated completely during the mash and there they come from, them dreaded bacterias!
 
You may be overstressing and missing out on a lot of the fun of brewing. You may be attempting to keep a steady mash temp for the full hour of the mash while your conversion was done in 15 minutes (not guaranteed but often happens). I've read that the enzymes that do the conversion are quickly denatured at mash temp and while they didn't define "quickly", my experience is that it happens way quicker than most brewers realize. Once denatured there is no further activity so your wort doesn't become way more fermentable.
I suppose it depends on your definition of "fun". Designing a recipe and knowing in my mind what I'm shooting for as far as taste, color, mouth feel, etc.....and then being pleased with myself for the result is what I consider fun. Being able to do that comes with experience and practice with my system, and consistent techniques. I've been to a lot of breweries, and I've been behind the taproom wall quite a bit. Of course conversion may be complete way faster than the ole 60-90 minute mash rule, but unless a pro is making a kettle sour or something like that, they aren't letting the mash sit all night and drop to room temperature. Maybe they aren't doing it that way for strictly the efficiency of not paying to heat up the first runnings in the morning but I doubt it. Either way, it doesn't matter. If you're making beer and you like the way it comes out.....who cares how it got there? I've had awesome homebrew from guys with a bucket and a kit. And some of the worse from guys with 10k in equipment. However you get it done.....get it done.

Cheers!
 
If you had so much bacteria on the bag that it caused a sour mash, next time wash the bag with some soap. At the end of the mash there should not be any bacteria surviving in the wort and very little will be able to get in if you have a lid on.
 
If you had so much bacteria on the bag that it caused a sour mash, next time wash the bag with some soap. At the end of the mash there should not be any bacteria surviving in the wort and very little will be able to get in if you have a lid on.

Apparently, bacteria don't care what they should or shouldn't do. The bag does not get immersed fully, so it won't be heated fully to mash temperature and during the night, the temperature drops to about 30-40c, that's the prime temperature range for lactos to thrive! They multiply really fast and do their job really quickly at that temperature.
 
You can add extract or water any time you see need for it. ;)
Add extract to the kettle (after the boil is done but before chilling) or add it to the fermenter (you may want to pasteurize it beforehand, for all security).

When the mash is done (e.g., saccharification rest, that's where the sugars are "formed") there's not much you can change. Keep notes, so next time you can adjust.

Coming up short in gravity happens to everyone, so make notes and, adjust for next time.
The whole trick is to arrive exactly at the recipe's OG (and volume) after the boil.

That involves a few variables, all depending on your equipment and techniques used, such as:
  1. complete conversion to maximize extracted sugars,
  2. in the composition/ratio the recipe is designed for,
  3. with good lautering and sparging to claim as much wort from the grist as possible,
  4. ending up with the correct volume AND gravity of your pre-boil wort.
Then after the boil, you should end up with:
  1. the exact volume of post-boil wort,
  2. at the recipe's intended gravity (that's your OG)
  3. and a bunch of other things, such as IBUs, amount of hop flavor, aroma, etc.
So...
You should try to aim for hitting that (really, not so) elusive OG (and volume) right on the nose.
After a few brews you should have honed in on that.

Your boil-off volume can only be determined during an actual boil on your equipment, You can start with an estimation of between 1/2 - 1 gallon boil-off per hour. And adjust accordingly on the next, and fine tune on the 3rd.

Here's a neat visualization for the mind:
Gravity and Volume are like a rubber band, the amount of sugar doesn't change (unless you spill it or leave some behind)
  • longer but skinnier ==> larger volume but lower gravity
  • shorter but thicker ==> smaller volume but higher gravity
If this all sounds a little like magic right now, after a few brews it will all make more sense.
As our homebrew mentor Charlie (Papazian) would say: RDWHAHB!
Thanks for those details - helps alot!!
 
I'm surprised that there are more than a couple of people doing over-nite mashes. I'm so anal about mash temps, that letting my tun cool to room temperatures after several hours makes me cringe. I strive on consistency, just letting it fly....not me. But if it works for you, more power to ya!
I use a temp controller and recirc pump while I'm away. It maintains mash temp indefinitely and recirc keeps mash temps even thought the entire kettle
 
Apparently, bacteria don't care what they should or shouldn't do. The bag does not get immersed fully, so it won't be heated fully to mash temperature and during the night, the temperature drops to about 30-40c, that's the prime temperature range for lactos to thrive! They multiply really fast and do their job really quickly at that temperature.
That happened to me once. I mashed in cold at night and let it alone until morning to turn the heat and pump on while I went to work. Sour mash was what I got. Now I set everything up at night but no grain until morning when I turn the kettle on. Everything else is the same.
 
Depending on where you are located but...
I mash and lauter at night. Then in morning I fire up the stove with wort and proceed like normal. I brew outside and the winter here only gets to a low of about 40f. I’ve brewed this way for the last 7 years (coincidentally the age of my kid) and have never had an issue w spoilage.

The only con is that I have to heat the wort from the 40s instead of 150s, which can take an extra 30 minutes or so. Usually that’s when I’m getting breakfast ready anyways.

This makes for a much less stressful brew experience. And since I’m mashing and lautering after kids go to bed, the impact to family time is much less= happier wife.
 
Although I personally wouldn't risk spoiling a batch with the overnigh mashing technique, I see as an useful option to be able to mash in the evening, arriving to the mash-out phase, maybe also do the sparge, then go to bed. The day after I could clean and sanitize the fermenter, do the boiling and hopping phase etc.

This splits the brewing session in two halves, without any change in the beer and any exposure to random infection or unwanted excess of conversion. The mash-out locks the mash profile and raises the temperature enough that bacterial infection is unlikely. The wort mass will need many hours to cool down to a temperature which favours infections. An insulated kettle will allow the splitting of the brewing sessions without side effects IMHO.
 
I'm an extended masher because I don't have much time for brewing and have lots of other things that I need to do. Is it the best way?
Probably not, but a 3 hour or overnight mash works just fine and I usually (ok not always) prefer my own homebrew over what the "professionals" at the local brewery are serving. Note I used be real fussy about maintaining mash temperature and fly sparging and stirring the mash, I suppose the "fun" of doing all that faded away and now I'm just a lazy brewer.
 
One (two?) time savers I utilize regularly are no-chill brewing and natural wort starters. In no-chill, you tap your hot wort directly from you BK into a food grade plastic container with a solid seal (US Plastics is a good online source). No air equals no chance for bugs to grow. The next day the wort is cooled enough to pitch yeast with no chiller cleanup, so about a half hour saved on brew day. Back to brew day, just before tapping the wort into the no-chill container, I collect enough wort for my natural wort starter (if needed) thereby not needing to either purchase or prepare dry DME for a starter a day os so before brew day. I just cool down 1-2 pints to recommended yeast temp , put it on a stir plate (or previously into a container on the counter that I shook every time I walked by), and by day 2 when your wort has cooled, you can pitch your yeast. Been doing this for years. Never had any infections or other evil things happening.
 
@porterguy I do much the same as your method. Except I just put the brew kettle outside to cool overnight with the lid on. I skip putting it into the food grade plastic container. It's worked well for me.

One additional step I do sometimes is if I'm rushed in the morning and don't have time to transfer to the carboy, then I just pitch the yeast into the cooled brew kettle. I then properly transfer to the carboy when I get home from work, and the ferment typically has started

Q: when you fill the food grade plastic container, do you fill it all the way so there is no airspace? Of do you figure the hot wort will kill off any bacteria that might be lurking in the air space?
 
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@porterguy I do much the same as your method. Except I just put the brew kettle outside to cool overnight with the lid on. I skip putting it into the food grade plastic container. It's worked well for me.

One additional step I do sometimes is if I'm rushed in the morning and don't have time to transfer to the carboy, then I just pitch the yeast into the cooled brew kettle. I then properly transfer to the carboy when I get home from work, and the ferment typically has started

Q: when you fill the food grade plastic container, do you fill it all the way so there is no airspace? Of do you figure the hot wort will kill off any bacteria that might be lurking in the air space?

It's a 6.5 or 7 gallon container, so there's always some airspace, although it's so airtight it actually collapses the container a little, decreasing the airspace. But I know nothing's getting in there, and have on occasion left it for several days, no problem. The wort goes in right after flameout, so it's easily still 200+ degrees. I don't even sanitize the container first; i just need to turn it over after 20 minutes so the hot wort kills any bugs on every surface. It's a long-used method from Australia, primarily used for water conservation, especially where they have limited water availability, like in the outback.
 
@porterguy @kmarkstevens

The common wisdom suggests a rapid chilling of the wort between boil and fermenter in order to prevent the formation of DMS during a slow cooling, which would remain in the beer.

That, in turn, is according to the common wisdom particularly important when brewing styles which "denonciate" the presence of DMS: mainly lager, pils.

Some malts appear to create less DMS than others: British "pale" should create less DMS than Lager or Pils malts.

Also, a long boil should reduce the DMS problem.

I think it would be interesting to know (from you and from other no-chill brewers) what kind of malts you use, what kind of boil you apply, and what kind of styles you brew.
 
I'm not a big lager or pils fan. I also tend to do 90 minute boils, and happen to really like British bitters and milds, and use either Maris Otter or mild malt. Mostly browns, porters, and stouts throughout winter. Rest of the year, pale ales, wheats, Belgian pale ales and patersbiers (so some pils use in these). I use Maris Otter as my base malt wherever 2-row is called for. I like the taste and since I buy in bulk it's one less 50 lb. bag to store. :)
 
The common wisdom suggests a rapid chilling of the wort between boil and fermenter in order to prevent the formation of DMS during a slow cooling, which would remain in the beer.

Please note that common wisdom may be wrong as proven by the people who do slow chills and still do not have excessive amounts of DMS.
 
Please note that common wisdom may be wrong as proven by the people who do slow chills and still do not have excessive amounts of DMS.

You probably did not read the rest of the message. The common wisdom is confirmed by user @porterguy because he, in fact, does not undergo the conditions which would - according to the common wisdom - advise for a fast chill.

I am not interested in polemics but in understanding. I find the answer by @porterguy very interesting. My question is aimed at understanding when fast-chill is important and when it is not.
 
... My question is aimed at understanding when fast-chill is important and when it is not.
Depends on how much SMM remains in the wort at the end of boil, how long the temp stays above ~170°F (where SMM to DMS conversion still occurs at an appreciable rate), whether the wort is still or being stirred/whirlpooled (affects egress of DMS from wort), and whether the vessel is covered/sealed (affects egress of DMS from wort.)

Brew on :mug:
 
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