Don't try this at home - False Bottom in Mesh Bag

[gatorforty]

Well, thought I should at least share my failure on here to hopefully prevent someone else from trying what I did.

I've been reading about "mashing in a bag" and other similar ways to try to clarify the wort leaving the Mash tun. I didn't have a bag big enough for my 10G mash tun, so instead I came up with the bright idea of putting just the false bottom (which feeds the drain valve) completely in a bag, kind of double filtering it.

Let me tell you...the first 12 ounces that left the MT were crystal clear, and then it stopped. LOL. Nothing. Nada. I could't get it flowing at all.

I ended up having to pour the whole mash into my brew kettle, remove the bag from the false bottom, and then pour everything back into the mash tun to drain it. Not a pretty process. If Hot Side Aeration is a real thing...this will be the test.

Just sharing my idiocy...for the good of the hobby, haha.

Ron

 

[Happywanderer]

Put the fine mesh bag loosely on the end of the drain hose going into your kettle.

I'd imagine that'd catch whatever makes it through your mash-tun filter/false-bottom/whatnot.

I don't do this as I don't mind a few floaters, but I might give it a shot to see how it works on my next batch of Kiss Me I'm Irish Red.

 

[blizz81]

Yeah, if you filter your runnings with the bag, you'll likely catch some stuff. That and the more vorlauf / recirculation you do, the more the grain bed can filter. Sounds like fun brewday times though!

 

[Yooper]

I did sort of the opposite last brewday. I have a bottom draining MLT with a nice false bottom, but some grain still gets through and ends up plugging up my drain, so that's a pain. I bought a new BIAB from Wilserbrewer, and put the bag ontop of the false bottom, and lined my whole MLT (using binder clips to hold it). It worked so well, and I recirculated the entire time without any grainbed compaction and no clogging! But, in the reverse, I could see it being a big problem.

 

[Happywanderer]

Hey Yooper. I'm thinking of doing this as well. Lining the MLT with a voile bag. Don't have a false bottom, so I've got to come up with a cheap way of making one.

Did you experience any issues with the bag? Did you squeeze it after draining/sparging to get the last little bit of wort?

I'm thinking with standard procedures of batch sparging and a good squeezing, I might get a 1%-2% efficiency bump.

 

[wilserbrewer]

I'm thinking with standard procedures of batch sparging and a good squeezing, I might get a 1%-2% efficiency bump.

You can squeeze all you want, but some of us have found just letting the bag drain for 30 minutes or more yields about the same volume.

I would think a FB is optional if using a bag, as you can always lift the bag up a bit if you are stuck. If recirc., I can see needing a FB.

Wilserbrewer
Http://biabbags.webs.com/

 

[ArkotRamathorn]

Well, if I am not mistaken, and assuming the hot-side-aeration exists, I don't think you'll have any issues. I believe that once you boil, any oxygen left in the wort is driven off until almost none is left.

 

[Yooper]

Hey Yooper. I'm thinking of doing this as well. Lining the MLT with a voile bag. Don't have a false bottom, so I've got to come up with a cheap way of making one.

Did you experience any issues with the bag? Did you squeeze it after draining/sparging to get the last little bit of wort?

I'm thinking with standard procedures of batch sparging and a good squeezing, I might get a 1%-2% efficiency bump.

I didn't squeeze. I was going to- but that bag of grain was darn near 170 degrees! I smooshed with my mash paddle a bit, and then said "f it" since that was my first BIAB anyway and I never squeezed before.

You can squeeze all you want, but some of us have found just letting the bag drain for 30 minutes or more yields about the same volume.

I would think a FB is optional if using a bag, as you can always lift the bag up a bit if you are stuck. If recirc., I can see needing a FB.

Wilserbrewer
Http://biabbags.webs.com/

It worked so well for me that I did it again today. I do recirculate throughout the mash, and go to mash out temps via recirculation (I have a HERMS). I have a false bottom with a stand, but did pull the grainbag up today when I batch sparged to remove some of the pressure (I had a vapor lock type of "stuck") and moving the bag just a bit released it and I was off to the races. :rockin:

 

[Happywanderer]

Thanks Yooper. This is definitely the route I'm going. Got to get my better half to break out the sewing machine this weekend.


Sent from my iPad using Home Brew

 

[beersk]

OP, why didn't you just put the bag over the false bottom like Yooper mentioned? That way, it would've been easier for you to remove the grains and clean your mashtun. This is what I do with a Coleman Xtreme 36qt cooler, but with a braided hose for my filter. It's great, I don't even vorlauf, it's not necessary. Cleaning the bag is the only real pain involved, but I don't clean it perfectly after use, just give it a general washing in the sink, hang dry, and then shake the rest of the dried grains off the next day or so.

 

[blizz81]

Yooper, was your recirc rate affected at all?


I've had a couple brews stick (both the same style) since I've gone recirc, seems with a FB (even with rice hulls) that you can't escape some grain matter coming through, especially right at the beginning of opening the valve. Last one I had to blow out through the drain, that got a bit messy.

 

[PHDrunk]

I've never used a false bottom, but I'm surprised the runoff got stuck with only the addition of the bag. I use a rectangular cooler and PVC manifold for my MLT. My first AG brew resulted in a terrible stuck sparge, so I started putting a voile bag around the manifold. Works like a charm -- no particulate, no stuck sparges, pretty good efficiency.

 

[pedimac]

I've been using the false bottom with a bag for a couple years now, no problems at all. Wife bought me a cooler, holds temps great, but had two stuck mashes with just the false bottom. Started using the bag, and it's great. The bag sits on top of the false bottom.

 

[Deckers_Beers]

OP, why didn't you just put the bag over the false bottom like Yooper mentioned? That way, it would've been easier for you to remove the grains and clean your mashtun. This is what I do with a Coleman Xtreme 36qt cooler, but with a braided hose for my filter. It's great, I don't even vorlauf, it's not necessary. Cleaning the bag is the only real pain involved, but I don't clean it perfectly after use, just give it a general washing in the sink, hang dry, and then shake the rest of the dried grains off the next day or so.

I'm thinking of doing that myself. Are you able to screw on the lid to your cooler with the bag over the top?

 

[JohnSand]

I'm thinking of doing that myself. Are you able to screw on the lid to your cooler with the bag over the top?

I do. I have the standard 40qt Coleman cylindrical cooler. I made the bag big enough to fold down the outside a bit, the lid screws on easily. I don't use a false bottom.

 

[LBF]

I just use a stainless braid in a 72 quart rectangular cooler. Vorlauf and go. Seems to work great and it's less to clean. I did BIAB for awhile and always hated dealing with the bag. If I would ever decide to go back to smaller batch stuff, I'll make a mini mash tun. Dump the grains, squirt it out good, and flip it over to dry. Done.