Sacch Rest - maintain the temp?

[Dale Gauthier]

Hi all, got 3 batches behind me. 2 BIAB and 1 extract. So still very green!

Following my latest recipe, I place my grain bag in the kettle at 165 degrees F and allow the wort to come down to 153 degrees F. Im supposed to kill the burner to let it rest for 60 min.

Question: Should I relight the burner if the temp falls too much? Is 10 degrees too much? I just wasn’t sure if I should pop the burner on for a minute to keep the temp up. OR should I let the temp fall so the mash enjoys a range of temperatures?

Thx so much!
Hd.

 

[RM-MN]

Ideally you would keep the temperature exactly the same for the entire time that it takes to complete conversion of starch to sugar. In practice, that time to complete conversion can be anywhere from 5 minutes for a very fine crush to 120 minutes for a very poor crush. With the poorer crush the temperature drop may affect the fermenatability of the wort as the two enzymes work together differently depending on the temperature and are activated as the starch gets gelatinized so as the temperature drops, the wort created becomes more fermentable resulting in a lower FG. For BIAB if you do your own milling you can get a pretty fine crush of the grain and a 10 degree drop over the course of an hour won't matter because the conversion will be over and the enzymes denatured before that temperature drop has much effect. For most of us with a crush in between flour and grains that are barely cracked, putting a winter coat, a sleeping bag, or some reflectix insulation over the pot is sufficient.

 

[wilserbrewer]

This is a very complicated topic that a book could be written about, but fortunately there are simple solutions that work pretty well.

My advice is to accurately hit your strike temp, dough in your grain and insulate your kettle for the mash rest. Then rdwhahb

Best to use a thorough crush to assure conversion happens fairly quickly.

Moving forward with subsequent batches you can raise or lower your strike temp to adjust attenuation if required.

This is my preferred method and what I like to call “simple” BIAB. Others prefer more precise and complicated methods involving recirculating pumps and computer controlled heating to maintain very precise mash temps, the benefit of which is up for debate...

 

[Dale Gauthier]

Ideally you would keep the temperature exactly the same for the entire time that it takes to complete conversion of starch to sugar. In practice, that time to complete conversion can be anywhere from 5 minutes for a very fine crush to 120 minutes for a very poor crush.

Thanks RM for that response! Lots of good info there for a rookie. My temps didn’t drop much but maybe 8-10 degrees. So I think insulation on the kettle would prevent me from firing up the burner again. Thx!

 

[Dale Gauthier]

This is a very complicated topic that a book could be written about, but fortunately there are simple solutions that work pretty well.

My advice is to accurately hit your strike temp, dough in your grain and insulate your kettle for the mash rest. Then rdwhahb

Thx Wilser. Simple solutions sound like a good idea to me. No need to further complicate - lol. I’ve been making wine now off and on for a few years. Had some mild success and learned a lot about the chemistry of alcohol and brewing but the beer is definitely much more complicated. Looking forward to brewing more. Thx!

 

[LittleRiver]

... I think insulation on the kettle would prevent me from firing up the burner again...

You didn't mention what type of heat you are using, but if it's propane Walmart sells a youth sleeping bag for $14 that fits rather perfectly over a kettle and burner. More info here.

 

[jrgtr42]

8 - 10 degree drop is pretty high, depending on how quickly it dropped.
Best is to try to keep it close. a couple degrees is fine, but try not to let it go much lower than that. So for 153 mash, maybe 150 should be about the lowest. As others said, when mashing, insulate the kettle to keep heat in. If you have a lid, put that on. Don't take it off too often - leave it be.
I use a cooler for a mash tun, keeps things pretty stable, but I'll open after maybe 5 minute to check what the temps are once they stabilized, then maybe give a mix halfway through.

 

[Dale Gauthier]

You didn't mention what type of heat you are using, but if it's propane Walmart sells a youth sleeping bag for $14 that fits rather perfectly over a kettle and burner. More info here.

That’s a great idea - lol. Yep propane bottle and a tall burner like a turkey fryer. I like the height so I can just open the spigot and fill my carboys. Now I just have to figure out how to get the most out my 15gal. kettle. Been researching if I should alter biab all grain recipes or not (3gal. not enough after all the time and cleanup). Sure would like to at least fill a 6gal. carboy at a time. But that’s another thread! Thx.

 

[Dale Gauthier]

8 - 10 degree drop is pretty high, depending on how quickly it dropped.
Best is to try to keep it close. a couple degrees is fine, but try not to let it go much lower than that. So for 153 mash, maybe 150 should be about the lowest. As others said, when mashing, insulate the kettle to keep heat in. If you have a lid, put that on. Don't take it off too often - leave it be.
I use a cooler for a mash tun, keeps things pretty stable, but I'll open after maybe 5 minute to check what the temps are once they stabilized, then maybe give a mix halfway through.

Good to know that 8-10 is too much. That’s what I thought as well. I’ll be insulating from here out for sure!

 

[JimRausch]

I'd be a little worried that you're doughing in at 165. At that temp, you're flirting with denaturing the enzymes. Hopefully it's cooling down to the 153 quickly.

 

[BongoYodeler]

Hi Dale, fairly new brewer here. Like you I also have a 15 gallon kettle. I heat with a (natural) gas burner. [Lucky I had a gas connection at the back of my house on the patio. I can swap the hose between the Weber grill and the Blichmann burner]. As stated above a finer crush should guarantee quicker conversion. I bought a grain mill and I've experimented with a crush between .022 and .025. I use brewing software to to tell me what temperature to mash in at. It seems to be quite accurate as my mash temperature is almost always dead-on after doughing in and stirring liberally. I put the lid on and cover the kettle with a moving blanket I got for free at Harbor Freight (they had a deal, free with any purchase). I then drape a cheapie sleeping bag over the moving blanket and secure it in place with two bungee straps around the kettle. On a nice 75° sunny day I generally lose only a degree or so over an hour.

 

[LittleRiver]

... Now I just have to figure out how to get the most out my 15gal. kettle. Been researching if I should alter biab all grain recipes or not...would like to at least fill a 6gal. carboy ...

I typically brew 5 gal batches in my 15gal kettle, it works great -- no worries of a boilover.

With a fine grain crush (~.025") you should be able to brew standard all grain 5gal recipes without modification and hit or exceed the target OG's of those recipes.

As I'm sure you already know, don't fill your carboys too full, or you could have a real mess. 5-5.5gal into a 6.5gal fermenter works well, but even then sometimes you need a blowoff tube.

 

[Dale Gauthier]

I'd be a little worried that you're doughing in at 165. At that temp, you're flirting with denaturing the enzymes. Hopefully it's cooling down to the 153 quickly.

Even as a rookie I thought the same thing. Books that I’ve read say that too high a temp would essentially shut it all down and limit fermentation big time. But I wanted to follow the Northern Brewer recipe to the letter until I feel competent enough to deviate. I will say that the temp dropped quickly when I put the bag in and my first 24 hrs in the carboy had a ton of action necessitating a blow off tube. So hoping that means it pulled enough sugars out. We’ll see!

 

[jrgtr42]

I'd be a little worried that you're doughing in at 165. At that temp, you're flirting with denaturing the enzymes. Hopefully it's cooling down to the 153 quickly.

I'd think it depends - if the strike water is at 165, then by the time everything equalizes, he should be pretty close to the target (depending on grain temp to start with.)
If he's targeting the dough-in at 165, then I agree - strike water being in the high 170s or something.
I personally don't BIAB, I use my cooler mash tun, but I spray it down with hot water from the tap to preheat it a bit, add a couple gallons of strike water, then mix in the grains. After that, I add the rest of the strike water. My thoughts are that the grain absorbs more heat, bringing the temps low, then adding the strike in later, it'll bring the temps back up to target. I can adjust how much I put in depending on temps - I can run a little thicker or thinner mash than I normally like if something's higher or lower temp.

 

[Cato1507]

This is a very complicated topic that a book could be written about, but fortunately there are simple solutions that work pretty well.

My advice is to accurately hit your strike temp, dough in your grain and insulate your kettle for the mash rest. Then rdwhahb

Best to use a thorough crush to assure conversion happens fairly quickly.

Moving forward with subsequent batches you can raise or lower your strike temp to adjust attenuation if required.

This is my preferred method and what I like to call “simple” BIAB. Others prefer more precise and complicated methods involving recirculating pumps and computer controlled heating to maintain very precise mash temps, the benefit of which is up for debate...

What Wilser said. My method as well.

 

[bracconiere]

I'd be a little worried that you're doughing in at 165. At that temp, you're flirting with denaturing the enzymes. Hopefully it's cooling down to the 153 quickly.

Is this actually an issue with BIAB, using more strike water?

 

[RM-MN]

Is this actually an issue with BIAB, using more strike water?

It can be depending on what temperature the grains are and the grain bill itself. Each batch that has a different weight of grain should have the strike temperature calculated.

 

[bracconiere]

It can be depending on what temperature the grains are and the grain bill itself. Each batch that has a different weight of grain should have the strike temperature calculated.

hmm, thanks for the info...i punched into beersmith, under mash. BIAB. And it says that for a light body, i would strike at 160f, not 165f....with 15lbs of grain in a 5gal batch, using ~38 qts of water. for a final temp of ~153f....

@Dale Gauthier You know for BIAB you use all the water in the first step? couldn't find it to quote it myself, but saw you'd like more then 3 gals...not sure if your using enough water? (and, yes that's kinda )

edit: and sorry, sorry, sorry in advance...just always get eager to help, a freshly born 'independent' drug user!

 

[wilserbrewer]

I'd be a little worried that you're doughing in at 165. At that temp, you're flirting with denaturing the enzymes. Hopefully it's cooling down to the 153 quickly.

While I agree, 165 seems kinda high, what is important is the actual grain temp.

During dough in the grain is heating up while the strike water is cooling down, so as the grain particles are absorbing the hot strike water, likely considerable simultaneous cooling is going on at the particle level, then continues to warm the grain particle until mash temp is stable.

In my little dream of being a mash grain particle, I never feel temps higher than the resultant stable mash temp....anyway that was my dream and I’m sticking to it...

 

[bracconiere]

W


In my little dream of being a mash particle, I never feel temps higher than the resultant stable mash temp....anyway that was my dream and I’m sticking to it...

i don't think i want THAT dream...what was your trip through the mill like?

 

[Dale Gauthier]

I typically brew 5 gal batches in my 15gal kettle, it works great -- no worries of a boilover.

With a fine grain crush (~.025") you should be able to brew standard all grain 5gal recipes without modification and hit or exceed the target OG's of those recipes.

Hey LittleRiver, since I've kinda gotten off topic, mind if I PM you to get some specifics on your 5 gal batch? Thx.

 

[Dale Gauthier]

hmm, thanks for the info...i punched into beersmith, under mash. BIAB. And it says that for a light body, i would strike at 160f, not 165f....with 15lbs of grain in a 5gal batch, using ~38 qts of water. for a final temp of ~153f....

@Dale Gauthier You know for BIAB you use all the water in the first step? couldn't find it to quote it myself, but saw you'd like more then 3 gals...not sure if your using enough water? (and, yes that's kinda )

edit: and sorry, sorry, sorry in advance...just always get eager to help, a freshly born 'independent' drug user!

No sorry's necessary! All this is good info for me!
Yep, for BIAB I'm using all the water upfront and in the first step. And noticing how much room I still have in my kettle got me thinking that I would sure like to yield more than 3 gallons next time. Between the brew time and the cleanup, 6 makes more sense. I just wasn't sure if I could double the BIAB recipe to make 6 gallons of beer instead of 3 or if it's not that simple where can I go to find out directions. I stumbled through the recipe page on Homebrewtalk but most everything I found regarding BIAB was 3 gallons.
Maybe I should have posted a new topic! Sorry all!

 

[wilserbrewer]

You can do ANY recipe w/ the BIAB method....only difference might be that you prefer a full volume mash.

 

[RM-MN]

No sorry's necessary! All this is good info for me!
Yep, for BIAB I'm using all the water upfront and in the first step. And noticing how much room I still have in my kettle got me thinking that I would sure like to yield more than 3 gallons next time. Between the brew time and the cleanup, 6 makes more sense. I just wasn't sure if I could double the BIAB recipe to make 6 gallons of beer instead of 3 or if it's not that simple where can I go to find out directions. I stumbled through the recipe page on Homebrewtalk but most everything I found regarding BIAB was 3 gallons.
Maybe I should have posted a new topic! Sorry all!

Using all the water up front works out well for BIAB but you are leaving fermentable sugars behind. If you kettle is large enough to do the 6 gallon batches, you might have enough room to add a sparge and get 7 gallons of beer from the same amount of grains. I'll make my 2 1/2 gallon batches and with the extra fine grind the mash efficiency is very high so I sparge to collect all the sugars that I reasonable can and end up with 3 1/2 gallons of wort. You may or may not have that kind of mash efficiency and you may not want the extra work/mess that sparging entails.

 

[LittleRiver]

...you are leaving fermentable sugars behind....you may not want the extra work/mess that sparging entails.

Without sparging I can hit or exceed targets for "normal" ABV beers with a process that is so simple and enjoyable I don't feel the need to add extra steps. I only sparge if I'm shooting for a high ABV.

I take my spent grains to the woods for the deer to eat. They probably appreciate that I leave them some sugars.

 

[CascadesBrewer]

And noticing how much room I still have in my kettle got me thinking that I would sure like to yield more than 3 gallons next time. Between the brew time and the cleanup, 6 makes more sense. I just wasn't sure if I could double the BIAB recipe to make 6 gallons of beer instead of 3 or if it's not that simple where can I go to find out directions. I stumbled through the recipe page on Homebrewtalk but most everything I found regarding BIAB was 3 gallons.

One thing I like about BIAB is how easy it is to swap between different size batches. I have been doing 5 gal batches outside on my propane burner and 2 gal and 2.5 gal batches on my stovetop. I find that 5 gal batches are really great when you are brewing a known recipe and smaller batches are great when you are tuning in a recipe or experimenting with different hops, yeast, malt, process, etc. 2 gal seems like a sweet spot for bottling, and 2.5 gal batches work for my newly acquired Torpedo kegs. Funny that you found 3 gal recipes as I see mostly 5 gal and 1 gal ones out there.

I keg my 5 gal batches, so I tune my volumes around trying to get around 5.0 gal out of the fermenter. If you bottle and have enough room in your kettle, and fermenter to support a larger batch, there is no reason to limit yourself to only 5 gals. Yes, you can basically double the ingredients of a 3 gal batch for a 6 gal batch. Your boil off amount might not be much different, so you might not need 2x the volume of water.

 

[CascadesBrewer]

You didn't mention what type of heat you are using, but if it's propane Walmart sells a youth sleeping bag for $14 that fits rather perfectly over a kettle and burner. More info here.

In my attempts to "be like LittleRiver" I also picked up a sleeping bag from Walmart. My 10 gal pot is fairly wide and the they had a thicker adult one for $24, so I went that route. This should let me do full volume mashes. It is long enough that I can double it up to have 2 layers over my pot. I guess I need to plan a 5 gal batch...I am brewing a 2.5 gal stovetop batch tomorrow.

 

[LittleRiver]

...I also picked up a sleeping bag from Walmart...thicker adult one for $24...

Does that one also have double zipper pulls? That's one of the things I like so much about mine, the zipper pull on the bottom of the sleeping bag (which end up on top of the kettle) lets me zip open the insulation to access the kettle lid, without removing the insulation.

 

[CascadesBrewer]

Does that one also have double zipper pulls? That's one of the things I like so much about mine, the zipper pull on the bottom of the sleeping bag (which end up on top of the kettle) lets me zip open the insulation to access the kettle lid, without removing the insulation.

It does.