First BIAB question

[Gusmedic]

I'm prepping for my first BIAB and I have a question on false bottoms. I bought a stainless steel mesh colander to place upside down in the bottle of the kettle before the bag and grains go in. The only concern is it's 5" tall and I'm afraid that'll take up too much space and only leave about 6" of water above the colander. Is this too small of water space to brew the BIAB? Do I need to find a small solution to keep the bag off the bottom? I see Amazon has pizza crisper trays that would fit, but only lift the bag about 0.75" off the bottom, and they're not stainless, they're a teflon coating. But I would assume that coating is safe to boil in if it's safe to cook with in an oven. What are your thoughts?

 

[Gusmedic]

After thinking it through a little more, since the colander is roughly half a sphere, I figured out the total volume it covered is less than 2 gallons, which is the same as a false bottom lifted 3 inches off the kettle. This 2 gallons of water the bag isn't in contact with doesn't seem as horrible as I first thought. Am I missing anything?

 

[dstockwell]

I have never used anything in the bottom of the kettle, and have never scorched the bag. I put the bag in the kettle and heat the water and stir it occasionally while I temp it for mash temp.

 

[bfish]

IMO a false bottom is not needed for direct fired or stovetop BIAB. Those that use electric elements might be, depending on their configuration. My wilserbag has a draw string that keeps it off the bottom. Others use binder clips to keep their bag off the bottom.

 

[mongoose33]

The concern I had--and still wonder about--is whether you're sequestering a lot of enzymes in the dead space beneath your hemispherical false bottom. If the malt has a lot of diastatic power that may not matter, but I wonder whether there's any qualitative difference.

 

[Morrey]

I have never felt the need for a false bottom with my BIAB setup. I go slightly over mash temp, drop bag in, then fill with grains for the mash. I then wrap kettle in a movers blanket and never seem to need to apply heat to stay within a degree or two of target temp. Should you find the need you can apply heat (at least I know propane is fine) as long as you keep the grains lightly stirred.

Some take the mash up to 168F after the completed mash cycle supposedly to denature the enzymes. I have never done that and cant determine the benefit for my brewing style since I am immediately heating to the boil after lifting out grains.

In typical scenarios, I never apply heat while the grains are in the kettle during the mash cycle.

 

[TheHopfather]

When I was doing BIAB it was 11L (3 gal) batches on my stove top, I've since moved on to a Grainfather. I didn't bother with a false bottom at all. I insulated my kettle with Reflect-X and if I was applying direct heat I would simply stir the grains the entire time, bag never once scorched.

I would think that you would want as much water to grain contact as possible. Your bag should be about the same dimensions as your kettle, so I would imagine you'd want the minimal amount of dead space below a false bottom as possible. However, I've never tested it before. You could always just give the false bottom a shot and see how the beer turns out. I think you could brew without it and be just fine as well.

 

[wilserbrewer]

I've never used anything in the kettle beside a bag and grain. If you need to adjust your mash temp, low heat and constant stirring.

No mash out needed.

 

[cubalz]

I have never used anything in the bottom of the kettle, and have never scorched the bag. I put the bag in the kettle and heat the water and stir it occasionally while I temp it for mash temp.

^yes this.

 

[OTHBrewing]

IMO a false bottom is not needed for direct fired or stovetop BIAB. Those that use electric elements might be, depending on their configuration. My wilserbag has a draw string that keeps it off the bottom. Others use binder clips to keep their bag off the bottom.

^^ I just use a bungee cord and wrap it around the bag that's folded over the top of my kettle to keep it from touching the bottom. Works well for me and have just always done it.

 

[violinguy]

Honestly, I've never considered using a false bottom. I'm three brew in right now and I haven't had to put fire to the kettle during the mash yet. I suppose that's where I'm lucky. I would do as the others said and you'll have no need for additional expensive equipment.

 

[owmatooth]

How do you get a musician off your porch?

Pay for the pizza.


rofl. took me a second, but then roflmao.

what ya need for biab is to figure out how to get than collander to stay supported over the top of the kettle to hold the grain bag while it drains after the mash. sounds like that one might be a bit too small, but $6.99 for the biggest one they have at walmart is a great investment in biab brewing. much easier than a ratchet and pulley system.

 

[doug293cz]

How do you get a musician off your porch?

Pay for the pizza.


rofl. took me a second, but then roflmao.

what ya need for biab is to figure out how to get than collander to stay supported over the top of the kettle to hold the grain bag while it drains after the mash. sounds like that one might be a bit too small, but $6.99 for the biggest one they have at walmart is a great investment in biab brewing. much easier than a ratchet and pulley system.

And a colander plus ratchet pulley system is even easier. Those bags are heavy when they first start coming out of the mash. I highly recommend this combo.

Brew on

 

[Gusmedic]

Well my first BIAB is in the books. It was hoping for 70% efficiency and I think i got 80%. Does this look right? My volumes were pretty much spot on and everything went very smooth.
Measured post mash gravity and measures preboil gravity are same thing in BIAB correct?

View attachment ImageUploadedByHome Brew1495226185.908629.jpg

 

[owmatooth]

yes post mash and pre boil would be the same, but I've never known to measure gravity before the wort is done with the boil and cooled.

Biab is great for me, and I get close to the same numbers. Now I'm focused on lowering fermentation temps to get a better yeast profile.

 

[fun4stuff]

I'm prepping for my first BIAB and I have a question on false bottoms. I bought a stainless steel mesh colander to place upside down in the bottle of the kettle before the bag and grains go in. The only concern is it's 5" tall and I'm afraid that'll take up too much space and only leave about 6" of water above the colander. Is this too small of water space to brew the BIAB? Do I need to find a small solution to keep the bag off the bottom? I see Amazon has pizza crisper trays that would fit, but only lift the bag about 0.75" off the bottom, and they're not stainless, they're a teflon coating. But I would assume that coating is safe to boil in if it's safe to cook with in an oven. What are your thoughts?

No need for a false bottom if your using a direct flame. Use a calculator to figure out strike temp. A little bit of heat won't hurt the bag if you stir continuously, which you should anyway to cut down on temp gradient. You should rarely if ever have to apply heat anyways providing you hit your strike temp.

 

[ericbw]

And if you do need to add heat, just raise the bag off the bottom. It's heavy but not impossible

 

[fun4stuff]

And if you do need to add heat, just raise the bag off the bottom. It's heavy but not impossible

Especially with a pulley

 

[RM-MN]

yes post mash and pre boil would be the same, but I've never known to measure gravity before the wort is done with the boil and cooled.

Biab is great for me, and I get close to the same numbers. Now I'm focused on lowering fermentation temps to get a better yeast profile.

I picked up a refractometer and usually take a gravity reading before I start the boil. It's a quick check that I didn't make big mistakes in the recipe or weighing the grains. It it were to be much lower than anticipated I can easily stretch the mash time out and add more grains to increase the OG or use some DME to do the same.:rockin:

 

[Gusmedic]

Just kegged my first BIAB and was shocked to find almost 1.5 gal of trub. Only kegged 4 gallons. Is this likely due to using a coarser cheap bag from Northern Brewer? Would a finer wisler or brew bag help with this. Not sure how or if all the junk in the bucket affected my OG reading.

 

[mongoose33]

That's after fermentation, you had a 1.5-gallon-thick layer of trub?

If you had a particularly fine crush, it's possible a lot of that flour and such would have made it through the bag into your wort.

 

[doug293cz]

Just kegged my first BIAB and was shocked to find almost 1.5 gal of trub. Only kegged 4 gallons. Is this likely due to using a coarser cheap bag from Northern Brewer? Would a finer wisler or brew bag help with this. Not sure how or if all the junk in the bucket affected my OG reading.

Yes, a finer weave bag will keep more of the fines out of your wort. I use a Wilser bag with a very fine crush (0.022" gap) and only get about 1/2 gal of trub at the the bottom of my fermenter.

Brew on

 

[owmatooth]

Just kegged my first BIAB and was shocked to find almost 1.5 gal of trub. Only kegged 4 gallons..

might have helped to cold crash the fermenter for a day or two before kegging. I'd get the wilserbrewer bag (i've got both that and the brew bag) and the couple of hop bags he sells as well. they're much bigger than the hop bags i've had before, so much more flow through them. I used to brew for a finished six gallons because of trub, but now with crashing the keg, i really only need to brew for 5 gallons. last few transfers to the keg left me with almost a gallon of beer left over.

 

[Gusmedic]

Thanks for all the replies. I just did my 2nd BIAB yesterday and have a question about temp loss during the mash. Twice during the 60 min mash my temp dropped about 2-3 degrees and I fired up the burner to a low flame while stirring for about 3-4 min until temps returned to my starting point.
I also switched to the wilserbag and it seemed good as new and no signs of melting with the added heat.
I see people talking a lot about insulating the kettles during the mash but they can still drop quite a bit over time. Is my adding a little heat with stirring during the 60+ min a good practice?

Also, even though I switched to a much nicer and finer bag, I still had about the same amount of trub in my pre-boil sample than with the other cheap bag. I anticipate the fermentation bucket will be about the same as last time. The previous person mentioned cold crashing. I did this for about 24 hours with the last batch that lost well over a gallon to trub. Would cold crashing and holding it cold for 3 days help compact that trub or make much of a difference?

 

[mongoose33]

Thanks for all the replies. I just did my 2nd BIAB yesterday and have a question about temp loss during the mash. Twice during the 60 min mash my temp dropped about 2-3 degrees and I fired up the burner to a low flame while stirring for about 3-4 min until temps returned to my starting point.
I also switched to the wilserbag and it seemed good as new and no signs of melting with the added heat.
I see people talking a lot about insulating the kettles during the mash but they can still drop quite a bit over time. Is my adding a little heat with stirring during the 60+ min a good practice?

Anything you can do to keep the temp as close to constant as possible will be a good thing.

I have found, using the hellfire burner, that there's retained heat in it so that after I wrap everything up, that retained heat is contributing to keeping the mash kettle up to temp.

Wrapping w/ a thin towel or similar isn't going to help much; you need some serious insulation around it. I use an old quilt that had been used for a paint drop cloth (not by me!) and that's barely good enough. Some use reflectix insulation around the kettle, others different kinds of approaches. If you insulate well enough, you won't have much temp drop at all. That you have as much drop as you do tells me that your insulation isn't very effective.

Also, even though I switched to a much nicer and finer bag, I still had about the same amount of trub in my pre-boil sample than with the other cheap bag. I anticipate the fermentation bucket will be about the same as last time. The previous person mentioned cold crashing. I did this for about 24 hours with the last batch that lost well over a gallon to trub. Would cold crashing and holding it cold for 3 days help compact that trub or make much of a difference?

I'm trying to figure out how you can have a gallon of trub. I use a wilserbag too, and while there's a little that gets through it, I'm not having anything close to that.

I typically have about a 10-12 pound grain bill, and I'm crushing the malt at about a .020 gap.

Here's what I typically get; it looks like more than it is, as the yeast settles against the curved side of the bottom, making it look like more than it is:

 

[Gusmedic]

Anything you can do to keep the temp as close to constant as possible will be a good thing.



I have found, using the hellfire burner, that there's retained heat in it so that after I wrap everything up, that retained heat is contributing to keeping the mash kettle up to temp.



Wrapping w/ a thin towel or similar isn't going to help much; you need some serious insulation around it. I use an old quilt that had been used for a paint drop cloth (not by me!) and that's barely good enough. Some use reflectix insulation around the kettle, others different kinds of approaches. If you insulate well enough, you won't have much temp drop at all. That you have as much drop as you do tells me that your insulation isn't very effective.



View attachment 406438









I'm trying to figure out how you can have a gallon of trub. I use a wilserbag too, and while there's a little that gets through it, I'm not having anything close to that.



I typically have about a 10-12 pound grain bill, and I'm crushing the malt at about a .020 gap.



Here's what I typically get; it looks like more than it is, as the yeast settles against the curved side of the bottom, making it look like more than it is:



View attachment 406439

Thanks for the reply. I don't mill and currently buy pre-crushed. I wish I would've taken a photo of my preboil sample, but my 8" test jar had at least 2" of junk that settled in the bottom as it cooled. Barley enough room for the hydrometer

Does the transfer from the kettle to the FV make much of an impact. Based on the brulosophy trial that showed no real clarity or taste change, I just dump in and leave the very last bit behind in the kettle. I don't siphon or whirlpool or anything.

 

[wilserbrewer]

Cold crashing for a longer period will settle the yeast cake and trub considerably.

When you say you cold crashed for 24 hours, imo that's not long enough, 5 gallons takes longer than that to chill to low temps in my refrigerator. 3-4-5 days is a cold crash imo.

 

[mongoose33]

Thanks for the reply. I don't mill and currently buy pre-crushed. I wish I would've taken a photo of my preboil sample, but my 8" test jar had at least 2" of junk that settled in the bottom as it cooled. Barley enough room for the hydrometer

Does the transfer from the kettle to the FV make much of an impact. Based on the brulosophy trial that showed no real clarity or taste change, I just dump in and leave the very last bit behind in the kettle. I don't siphon or whirlpool or anything.

That's what I do.

You might consider buying a refractometer. I never use my hydrometer except after fermentation is complete or if I'm trying to hit the midpoint in fermentation.

I take that refractometer reading either just before chilling the wort or just after. When I chill, once I hit my target temperature I remove the chiller and cover the boil kettle while I rinse off the chiller. I'll come back in a few minutes and then rack into the kettle, trub and all.

It looks ugly in there initially, but if I let it sit I'll end up with 4-6 inches of....stuff in the bottom. That's normal. It's the hot break and cold break and hop material, and it's fluffy.

After fermentation is complete, it will all pack down to what you see in the pic in my previous post.

I just brewed a beer on Thursday, doing an accelerated lager schedule fermenting halfway to complete attenuation, then bumping it up to 66 degrees to finish. The below pic is where it is now, just bumped it to 66 degrees this morning.

I dumped in all the trub, and it's a BIAB using a wilserbag, the grain bill was about 11 pouinds.

If your trub isn't packing down like that, I'm wondering what else is going on.