Suggestions for keeping BIAB bag off bottom?

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eljefebrewing

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My kettle is approximately 16" inner diameter at the bottom. I have done a lot of searching on Amazon, restaurant supply sites, etc. for a round rack that would keep my brew bag off the bottom of the kettle. I haven't really found anything that looks like a good solution. Anybody have suggestions or creative ideas?
 

jtratcliff

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Maybe .... don't worry about it?

I direct fire my 10G Aluminum tamale pot with my wilserbrewer bag all the time. Never had a scorch... Of course I'm stovetop, not on a 100K BTU jet burner.

Do you have any specific reason to fear scorching at mash temps? As long as you're stirring and not totally blasting a flame you should be OK.
 
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eljefebrewing

eljefebrewing

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Just thinking preventatively. My current bag is a cloth job that my mom custom sewed for me. I haven't used voile before, but had read that you should keep it off the bottom when the flame is on. I have a Bayou Classic burner. If you do it successfully, then maybe I won't worry about it! Cheers!:mug:
 

jtratcliff

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My kettle is fairly thin aluminum and I've not had any scorching. While I do stir the whole time the flame is on, it is usually turned up fairly full. I don't know how many BTUs that one burner puts out though.

I usually only need to fire it on high once or twice for a minute or 2 at a time to get my temps back in check. I can leave it on med-low without even stirring. Melting point for voile is around 250C I think I read somewhere...

So even though the bottom of the pot does get hot, I would think the wort at mash temps would buffer the heat and as long as you stir, you shouldn't get anywhere close to melting.
 

DurtyChemist

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I brew in a keggle. I use the big black binder clips to hold the bag to the keg handle when heating. You can find them at any office supply store.
 

Chris7687

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I do eBIAB and I leave my bag directly on the heating element while it maintains 154*F while mashing and have no problems with melting. It is voile. I haven't had any problems with it. I think the whole bag melting on the bottom is a myth, as I haven't seen one photo to support the notion.
 

bu_gee

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Do you have a suitably large colander? It might even work if it is plastic, though I'd do a test fire to make sure it doesn't melt too.
 

bu_gee

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I do eBIAB and I leave my bag directly on the heating element while it maintains 154*F while mashing and have no problems with melting. It is voile. I haven't had any problems with it. I think the whole bag melting on the bottom is a myth, as I haven't seen one photo to support the notion.
A large gas burner will output an order of magnitude more power than even the most powerful electric elements.

The notion isn't outside the realm of possibility especially if the heat gets trapped between your kettle and the grain bed.
 

Chris7687

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A large gas burner will output an order of magnitude more power than even the most powerful electric elements.

The notion isn't outside the realm of possibility especially if the heat gets trapped between your kettle and the grain bed.
Note that the 'grain bed' isn't a large dense mass at the bottom of your kettle. The grain, for the most part, is in suspension.

Also, for the brief time that your burner is on and your stirring like a crazy person (to keep from scorching the wort), there should be no heat build up down there to come close to melting a voile cloth. I also use a propane burner, when doing smaller 2.5-5g batches, and again have never had any problems here.

A big boogie-man myth if you ask me. Just trying to save everyone some headache and lightening their wallets.
 

bu_gee

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You and I are arguing around the same point. Maybe practically speaking it shouldn't happen, but if stuff does go wrong and you can't stir or your grain had dense bits that day, or you're just an unlucky sucker, it could happen.

No sense in not hedging your bets especially if it is a cheap fix.

Personally, I think a false bottom is there more to protect electrical heating elements from mechanical stress than to protect the bag from scorching.
 

firerat

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When i first began BIAB I worried about the same thing.

So I lined the bottom of my kettle with upside down 1/2 pint mason jars to keep the bag off the bottom. I had a butt ton of them and they did the job. It made draining the kettle kind of a bear but it worked.

I don't bother with it anymore though. I use a Bayou Classic burner and never have had a scorching issue.
 
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I don't BREW in a bag - I MASH in a bag. So the flame is almost never on. I mash in with the heat off and *maybe* give a few bursts of heat once in a 60 minute mash. If I do flame on, I gather the bag at the top, lift it an inch and bump it up and down a few times to move the wort around in the kettle. When I kill the heat I drop the bag, stir and recover. I tend to have no more than 12 pounds of grist in the mash, so heavy is not an issue.
 

fj605

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If you're not stirring while the burner is on, you can melt nylon bags. I can't vouch for other materials.
 
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For my setup the rack helps keep wort flowing during continuous recirculation. The fabric of my bag is so tight I need the surface area for wort to drain fast enough.
 

RM-MN

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If you're not stirring while the burner is on, you can melt nylon bags. I can't vouch for other materials.
Why are you heating while the bag is in the pot? You're doing a BIAB mash with nearly the full volume of water and you should have your grains milled fine for the BIAB. With that, your conversion will be done in such a short time that there is no need to heat the pot unless you are brewing outside when it is below zero and if you are doing that I question your sanity. Your large volume of water won't lose much heat before conversion is complete.
 

dkevinb

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Why are you heating while the bag is in the pot? You're doing a BIAB mash with nearly the full volume of water and you should have your grains milled fine for the BIAB. With that, your conversion will be done in such a short time that there is no need to heat the pot unless you are brewing outside when it is below zero and if you are doing that I question your sanity. Your large volume of water won't lose much heat before conversion is complete.
I heat with the bag in the pot when I'm raising the temp to mash-out. But I have a tamale steamer with a steamer rack, so the bag is about 2" off the bottom of the pot.
 

RM-MN

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I heat with the bag in the pot when I'm raising the temp to mash-out. But I have a tamale steamer with a steamer rack, so the bag is about 2" off the bottom of the pot.
Then the question becomes, "why are you doing a mashout with BIAB?" Mash out is a valid technique when you are fly sparging in a conventional mash tun. Are you fly sparging? Do you use a conventional mash tun while you are BIAB brewing? When you pull the bag of grains out of the pot you start the burner and quickly raise the temperature to start the boil. That denatures the enzymes faster than a mash out which is supposed to take 10 minutes at 170.
 

dkevinb

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Then the question becomes, "why are you doing a mashout with BIAB?" Mash out is a valid technique when you are fly sparging in a conventional mash tun. Are you fly sparging? Do you use a conventional mash tun while you are BIAB brewing? When you pull the bag of grains out of the pot you start the burner and quickly raise the temperature to start the boil. That denatures the enzymes faster than a mash out which is supposed to take 10 minutes at 170.
I am not sparging. I do it for the same reason I do most things relative to brewing - I read it somewhere. It is claimed to increase efficiency slightly. I've never tried not doing it, though I think I will for my next batch. If it saves me 15-20 minutes and a little work and doesn't affect the beer, why not get rid of that step?
 

ClunkClunk

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An expandable/collapsable vegetable steamer basket is what I use to keep the bag off the bottom. Once in a while my mash temp drops a bit low and I like to add a touch of heat while stirring to bring it back in line, even with full volume mashes.

I melted a hole in one of my bags before I did this, so I'm a touch more careful now.
 

doverox

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i was wondering about this too in anticipation of my first biab batch.

i have a turkey fryer that came with a basket insert and a hanger to lift it. I was thinking of placing the hanger at the bottom laying it down flat, resting the straining basket on top and placing the bag over it. any potential issues if i do this?
thanks
 

RM-MN

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I am not sparging. I do it for the same reason I do most things relative to brewing - I read it somewhere. It is claimed to increase efficiency slightly. I've never tried not doing it, though I think I will for my next batch. If it saves me 15-20 minutes and a little work and doesn't affect the beer, why not get rid of that step?
You've probably also read that you should mash for 60 minutes but 3 weeks ago I made a saison, mashed for only 20 minutes. OG of 1.057 and the gravity after 17 days was 1.000. Did I get full conversion in only 20 minutes of mashing?
 

RM-MN

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i was wondering about this too in anticipation of my first biab batch.

i have a turkey fryer that came with a basket insert and a hanger to lift it. I was thinking of placing the hanger at the bottom laying it down flat, resting the straining basket on top and placing the bag over it. any potential issues if i do this?
thanks
That should present no problems but if you read through this thread, some of us are suggesting that you don't need to worry about melting the bag if you don't have the heat on with the bag inside the pot. Just bring the water to your calculated strike temp (full or nearly full volume of water for BIAB), turn off the heat, drop the bag in and stir in the grains. You can insulate the pot if you want. When the mash period is done, pull the bag out and turn the heat back on.
 

jtratcliff

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You've probably also read that you should mash for 60 minutes but 3 weeks ago I made a saison, mashed for only 20 minutes. OG of 1.057 and the gravity after 17 days was 1.000. Did I get full conversion in only 20 minutes of mashing?
Sorry to thread jack, but I've been following RM-MN's flash-mashing exploits in other threads. I'm curious RM-MN, have you ever compared two batches that differ only by length of mash? Same grist, same boil, same hopping, same yeast, etc. Just a 60 min mash vs 10 or 20 min.?

I've been shortening my mash times based on some of the results you and others are reporting but I'm still not 100% convinced that getting full conversion as indicated by an iodine test is the full story.

That said, I do sometimes lose a degree or 2 in the first half hour and direct fire to bump things up. Thin walled aluminum tamale pot and no insulation. I also "mashout" my dunk sparge in the 2nd pot. I figure it can hurt to lower viscosity a bit and it gets hotter wort to add back to the main kettle.

Edit to add:

I've still never scorched my bag.... I do squeeze it though, Ouch!
 

dkevinb

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Sorry to thread jack, but I've been following RM-MN's flash-mashing exploits in other threads. I'm curious RM-MN, have you ever compared two batches that differ only by length of mash? Same grist, same boil, same hopping, same yeast, etc. Just a 60 min mash vs 10 or 20 min.?

I've been shortening my mash times based on some of the results you and others are reporting but I'm still not 100% convinced that getting full conversion as indicated by an iodine test is the full story.

That said, I do sometimes lose a degree or 2 in the first half hour and direct fire to bump things up. Thin walled aluminum tamale pot and no insulation. I also "mashout" my dunk sparge in the 2nd pot. I figure it can hurt to lower viscosity a bit and it gets hotter wort to add back to the main kettle.

Edit to add:

I've still never scorched my bag.... I do squeeze it though, Ouch!
I've been listening to some old interviews with Kai Troester on Basic Brewing Radio and he makes the point that just because the iodine test is negative you shouldn't cut the mash short. I don't have enough experience with it one way or the other to know. I think the only way to find out is to do a split batch - mash for 20 minutes and run off half, then continue to mash the other half for the rest of the 60 minutes, then treat the two worts identically afterwards. You'd then have to have help to do a double blind tasting at the end.
 

jtratcliff

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I've been listening to some old interviews with Kai Troester
Reading some of his experiments on his site is part of what's keeping me from going too short....


mash for 20 minutes and run off half, then continue to mash the other half for the rest of the 60 minutes
I think Yooper pointed out a flaw in this methodology in an earlier thread... Your pH will change when you pull off half the wort. You're possibly better off doing 2 separate but equal :) mashes. Slightly harder to get identical temps though.

Maybe do 2 separate bags? Half the grist in each bag. At 20 minutes, pull one bag and run off half the wort? Should maintain the same mash thickness... but you need good grain absorption numbers to know how much half the wort will be....

A triangle test may be easier than double blind....
 

dkevinb

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Reading some of his experiments on his site is part of what's keeping me from going too short....




I think Yooper pointed out a flaw in this methodology in an earlier thread... Your pH will change when you pull off half the wort. You're possibly better off doing 2 separate but equal :) mashes. Slightly harder to get identical temps though.

Maybe do 2 separate bags? Half the grist in each bag. At 20 minutes, pull one bag and run off half the wort? Should maintain the same mash thickness... but you need good grain absorption numbers to know how much half the wort will be....

A triangle test may be easier than double blind....
Yeah, it's really hard to change just one variable in these experiments. "Separate but equal" has never worked well, historically speaking.
 

RM-MN

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Sorry to thread jack, but I've been following RM-MN's flash-mashing exploits in other threads. I'm curious RM-MN, have you ever compared two batches that differ only by length of mash? Same grist, same boil, same hopping, same yeast, etc. Just a 60 min mash vs 10 or 20 min.?

I've been shortening my mash times based on some of the results you and others are reporting but I'm still not 100% convinced that getting full conversion as indicated by an iodine test is the full story.

That said, I do sometimes lose a degree or 2 in the first half hour and direct fire to bump things up. Thin walled aluminum tamale pot and no insulation. I also "mashout" my dunk sparge in the 2nd pot. I figure it can hurt to lower viscosity a bit and it gets hotter wort to add back to the main kettle.

Edit to add:

I've still never scorched my bag.... I do squeeze it though, Ouch!
I have not tried 2 identical batches. I like a variety of beers and there always seems to be more recipes to try than what I can drink up. I did a saison 3 weeks ago with a 20 minute mash and in 17 days it went from 1.057 to 1.000 so I think I have good conversion with plenty of fermentability. That recipe I had set the software to calculate my grain bill at an 85% efficiency.

Maybe I should redo that recipe with a 10 minute mash but it wouldn't be identical because I don't have the half packet of Belle Saison yeast that had been sitting opened in my refrigerator for 6 months.
 

bu_gee

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I have not tried 2 identical batches. I like a variety of beers and there always seems to be more recipes to try than what I can drink up. I did a saison 3 weeks ago with a 20 minute mash and in 17 days it went from 1.057 to 1.000 so I think I have good conversion with plenty of fermentability. That recipe I had set the software to calculate my grain bill at an 85% efficiency.

Maybe I should redo that recipe with a 10 minute mash but it wouldn't be identical because I don't have the half packet of Belle Saison yeast that had been sitting opened in my refrigerator for 6 months.
I guess the question that I have is what did your grain bill look like and what your procedure was to achieve that. If you've stumbled on a faster way to get the same results, many of us would be interested to know how to replicate it.
 

RM-MN

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I guess the question that I have is what did your grain bill look like and what your procedure was to achieve that. If you've stumbled on a faster way to get the same results, many of us would be interested to know how to replicate it.
The main thing that makes a shorter mash possible is the fine milling of the grain and the guts to try it. You can't really do a short mash with the conventional mash tun because if you mill the grains fine you can't get the wort out of the tun. BIAB and the huge filter area of the bag allows the fine milling.

Try a small batch. Mill the grains to cormeal consistency and start a mash with the lid off. Watch how long it takes for the liquid to go from milky to clear. When the liquid clears, the starch is gone, changed to sugars. Now the question is when the dextrines produced by alpha amylase are broken down into fermentable sugars by the beta amylase. I let my mash go anywhere from 7 to 20 minutes after the wort clears to allow time for the beta amylase to work. For my grain milled as fine as they are, that equates to 10 to 20 minutes in the mash. I know from doing several batches that 20 minutes of mashing gives me a very fermentable wort. I need time to do more of the 10 minute mashes to verify the fermentability of the wort produced.
 

bu_gee

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Two questions/issues I have off the bat:

1. Not everybody is after a highly fermentable wort, such as I. Traditionally, this is attributed to mash temperature and not duration. This is why I was asking about your procedure. I think I wouldn't be able to replicate your results without knowing your volumes (vessel(s), in, out, sparge, etc.) and your temperatures.

2. Doesn't the more finely milled grain hold on to more water? What if any is your sparge procedure?
 

RM-MN

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Two questions/issues I have off the bat:

1. Not everybody is after a highly fermentable wort, such as I. Traditionally, this is attributed to mash temperature and not duration. This is why I was asking about your procedure. I think I wouldn't be able to replicate your results without knowing your volumes (vessel(s), in, out, sparge, etc.) and your temperatures.

2. Doesn't the more finely milled grain hold on to more water? What if any is your sparge procedure?
Good questions. Here is the grain bill. The batch size was 2.75 gallons in a 5 gallon stainless steel pot.

4LB pale malt (Rahr)
1 LB rye malt (Briess)
4 OZ caramel 10L (Briess)
2 OZ Coffee malt (simpson) late addition

.350 (estimated) Nugget hops 13.5% 28 IBU

Belle Saison yeast

Mashed at 155F. for 20 minutes in 3.75 gallons, pour through sparged with cold tap water to get my pre-boil volume (about 1 qt) of 3.75 gallons.

Note that Belle Saison yeast is a monster. The previous batch had an OG of 1.060 and a FG of 0.995 using roughly the same procedure with the exception that I raised the temperature during the ferment starting at 62 for a week, 2 weeks at 72 and finally finished at 85 for 4 days.

Note also that the finely milled grains don't hold much water by the time I'm done squeezing.
 

bu_gee

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That is indeed impressive. I wonder if I could replicate it.

Are you adding the grains at 155 and then boosting back or do you add them at a higher temp?

I would want a less fermentable wort than you're creating so I want to adjust my temps accordingly.


I am wondering if most of your conversion happens after you pull the grains out of the starchy water. Do you mash out before pulling the grains? Could you give me a rough sense of the timeline between pulling the grain and starting your boil?
 

RM-MN

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I bring water to the indicated strike temperature and then stir in the grains. Using a different yeast would make a beer that wouldn't ferment out so far, the Belle Saison yeast seems to be the difference.

I pull the bag of grains out and then turn my stove back on high to get to a boil. While it is heating the water, I use cold tap water to do a pour through sparge and add this back to the pot. With that colder water sparge it takes almost 20 minutes to have the water boiling. The water is no longer starchy when I pull the bag. If you were to keep the pot open and watch, you'd first see the starchy water which is indicated by the cloudiness. That is soon clear as the enzymes convert the starch to sugar. The testing I did earlier with using iodine for the indicator of remaining starch says that happens in less than 3 minutes. It will take longer than that for the beta amylase to break long chain sugars to fermentable sugars which is why I gave this batch the 20 minutes.
 
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