BIAB Disadvantages to go with the Advantages thread.

[TheMadKing]

To me, that is easier than scooping out grains from a vessel, then cleaning the vessel.

I do about 10 quick scoops, shopvac out the rest, and CIP along with my BK, chiller, and HERMS coil at the end of the brew day. The only thing I disassemble is my Mash tun dip tube to remove the false bottom to clean under it - otherwise its pretty effortless to clean. Getting the grains out is about the same amount of effort as dumping the bag and then cleaning it to get all the grain particles off, maybe even slightly easier

 

[porterguy]

And it is the easiest and fastest and cheapest way to get newbies to all-grain brewing in the game.

Absolutely the biggest plus is allowing people to try AG without first buying a mash tun, etc. etc.. You can get a 5-gallon paint strainer bag for a couple bucks at a big box store, and you're ready to try AG via BIAB. Then you can either stay with BIAB, or decide to dive into AG with all the additional equipment options.

Somewhat similar to the disagreements about no-chill brewing. You can use a no-chill container, make a real wort starter from that day's brew, and pitch your yeast the next day. Or you can chill with cold water, in a sink, or using a regular chiller, or a recirculating chiller, or a plate chiller. Some people choose to just let it cool in the kettle until down to pitching temp.

One of the best things about homebrewing is there are a whole lot of "right" ways to get it done, allowing everyone to have a lot of individual input into what works for them. A really cheap system with a lot DIY, or a bigger setup with all the bells and whistles (no offense intended, to each his/her own).

 

[LittleRiver]

...scoops, shopvac.....CIP....disassemble... remove the false bottom............its pretty effortless to clean...

Thank you for making my point that dumping and rinsing off a bag that already contains all the grains is a lot easier and quicker than all of that.

 

[TheMadKing]

Thank you for making my point that dumping and rinsing off a bag that already contains all the grains is a lot easier and quicker than all of that.

I used to BIAB.. Its not really much faster.. Maybe 3-5 minutes for grain disposal

And you also have to clean your kettle/mash tun at the end.

 

[Saffersa]

Has anyone else noticed that BIAB really isn't a discrete thing anymore? The diversity of systems using bags (calling themselves BIAB) is enormous - a far cry from the original single pot with a bag. Brewer A uses a traditional 'no sparge' method and says BIAB has the advantage of speed, ease and not much cleanup. Fantastic. But efficiency takes a hit. Brewer B....'efficiency is better with BIAB - take the bag out and sparge over the top and give it a good squeeze'. OK, but you've just added a step (and, IMO a messy one). That's good as well, but it's still hard to do step mashes without the need to stir. Brewer C 'but it's easy, stick the bag in a mash tun and recirculate through a RIMS tube'. A fantastic method, and works well (I often use the method) but moves even further from the simplicity of traditional BIAB and takes away the advantage of being able to use a very fine crush. I see some BIAB setups that are so blingy they make my homemade 3v system look like a clunker (to be fair, they still don't compare with off-the-shelf 3v systems for blingyness). Again, not really in the spirit of the original BIAB.

What's my point (tldr)? A bag is nothing more than a manifold/false bottom/bazooka screen. Your system has more to do with the number of vessels, heating method, sparge system etc. than it does the grain filter. BIAB isn't a true group. I know I'll get some hate for saying this, which is OK.

FWIW, I sometimes BIAB, sometimes use my cooler mash tun with bazooka, and sometimes use my keggle mash tun with false bottom. All three may or may not use a RIMS tube. I decide based on what I'm brewing and how much of it. Brew with whatever you've chosen and be happy with it. My personal 'dislike' with using a grain bag (and each system has 'dislike(s)') is the messiness of handling the bag.

 

[Saffersa]

Hi Gnomebrewer

See...homework.
I think you've saved me a lot of time and effort. Was wondering about trying out a bag in my mash-tun, to maybe make the clean-up easier and faster, but I'll still have to do a proper clean on the mash-tun and copper manifold anyway but now with added step of cleaning the bag. Seems like more hard work.

 

[Gnomebrewer]

If you have a mash tun that's fixed in place or difficult/heavy to move or difficult to empty, the bag will definitely save you time and effort. Also, you could consider using the bag in place of the copper manifold - if you do that, you can crush much finer = better efficiency and faster conversion. BUT, it means recirculation (if you do it) isn't as effective because the grain bed won't filter well, and fly sparging (if you do it) doesn't work as well for the same reason.

 

[Saffersa]

The mash tun is a converted steelbelted coleman cooler box so quite manageable to move around etc.
Going to have to homework on the recirculation.
currently batch sparging, due to limited means.
Maybe in a few brews tme I will relook at it again
Thanks for the info

 

[Gnomebrewer]

You don't need to recirculate (unless you're running RIMS or HERMS). No problems with batch sparging either. It sounds like a bag could be useful for you - if you mostly do single temp infusion in your cooler, stick a bag in it instead of the manifold and you'll be able to use a much finer crush.

 

[Hwk-I-St8]

I do about 10 quick scoops, shopvac out the rest, and CIP along with my BK, chiller, and HERMS coil at the end of the brew day. The only thing I disassemble is my Mash tun dip tube to remove the false bottom to clean under it - otherwise its pretty effortless to clean. Getting the grains out is about the same amount of effort as dumping the bag and then cleaning it to get all the grain particles off, maybe even slightly easier

Don't you then have to clean the shop vac?

 

[TheMadKing]

Don't you then have to clean the shop vac?

Not really actually - I just dump the grains out of it, and then when using it during the rest of my cleaning process it gets cleaned as a byproduct of sucking up PBW water.

 

[Ninoid]

For pure homebrewing and making 5 gal batches for personal use BIAB is the best possible technique. If you live in a small apartment and want to make your own all grain beer there is no better way.

 

[Gruel]

I added a bag to my sparge setup, but I'm still looking to improve my setup and procedure. I just brewed another 5 gallon Weizen batch yesterday: the bag is in the way when stirring the mash during temperature step-ups, and so far it seems to increase the likelihood of spilling sugar water (sweet wort) onto the top of the gas range, which, if I don't catch all of it, burns in during the wort boil.

I'm thinking a cylindrical metal mesh insert for the mash kettle might work better for my setup than a bag?
Like this here: Kegco XMB-6 Stainless Steel Cold-Brew Iced Coffee Filter Basket for 6 Gallon Brew Kettles | BeverageFactory.com
How does it work for brewing? I might post a new thread (after doing a search).
Update: the 84 micron / 200 mesh mesh might be too fine for brewing. 400 micron / 40 mesh is apparently more appropriate.
www.utahbiodieselsupply.com/brewingfilters has some 800 micron strainers (too course ?) and custom mesh size filters.

 

[Ninoid]

That basket works like a bag, but you need to have some sort of pressing system to squeeze grain.

 

[radwizard]

I had a single vessel BIAB , which I ultimately added a second vessel. There were a number of reasons that adding the second vessel just made sense in having a superior system.
I never really understood the clean up issues with adding a new vessel. It literally takes minutes for me to clean my mash tun.

 

[Gruel]

radwizard, I'm not sure what the number of vessels has to do with using a brew bag or filter. I'm using between three and four vessels typically (I'm trying to do 5 gallon brews with two 5 gallon kettles , so I need one or two additional small vessels for Vorlauf handling and intermediate wort storage), but for the mash&sparge vessel I would still like a better setup; the bag helps with getting the grain out, but it does add some sloppiness to the whole process that I would like to avoid (bag folding over the edge of the vessel, bag flopping around inside the vessel). The washing of a few tuns or kettles is not a problem, I completely agree.

Ninoid, in the past when I didn't use a bag at all, I got satisfactory efficiency just sparging. With the bag, I agree that it's tempting to wring a bit of the remaining liquid out, but I think realistically we are talking about maybe a percent gain in yield here (1 pint of 1.02 density wort, out of a total of 5 gallons at 1.05 density).

 

[Gnomebrewer]

I think realistically we are talking about maybe a percent gain in yield here (1 pint of 1.02 density wort, out of a total of 5 gallons at 1.05 density).

At mid 80's% efficiency, you'd need about 8lbs of grain for a 5 gallon 1.050 batch.
Grain holds about 0.12 gal/lb, which means about a gallon of wort left in your 8lbs of grain. Squeezing will get at least half of it, which is 1/2 a gallon. 1/2 a gallon of 1.020 wort (if that's what you're left with after sparging) is 2 points of gravity over 5 gallons. 2 points of gravity in the 1.050 range is 4%. So efficiency is improved about 4% by squeezing the bag. That matches quite closely with @doug293cz chart (below) for double sparged wort.

 

[LittleRiver]

...So efficiency is improved about 4% by squeezing the bag...

What bag? Is it a bag that was separated from the wort a few seconds ago? Or is it a bag that has been fully drained by gravity, hanging over the kettle for a full hour during the boil?

In the latter case there will be nowhere near 1/2 gal (8 cups) left in the grain. It's closer to 1 cup.

To me that one cup is definitely not worth the sticky mess of squeezing.

 

[Gnomebrewer]

What bag? Is it a bag that was separated from the wort a few seconds ago? Or is it a bag that has been fully drained by gravity, hanging over the kettle for a full hour during the boil?

In the latter case there will be nowhere near 1/2 gal (8 cups) left in the grain. It's closer to 1 cup.

To me that one cup is definitely not worth the sticky mess of squeezing.

It was posted on here a while ago that hanging the bag for the hour gets roughly halfway between an immediate draining and a good squeeze. I'm not sure how accurate that is, but it would mean a 2% increase in efficiency (at the given gravity) over no hang, and another 2% to be gained by squeezing.

I didn't say anywhere that it was worth squeezing - I also don't squeeze because I don't like the stickiness and couldn't care less about 4% efficiency. I was just pointing out that there's more than one percent to be gained by squeezing a bag.

 

[ChiknNutz]

As a point of reference, I finished my first BIAB just yesterday and did squeeze the bag. I had planned to do so from the beginning and picked up the appropriate gloves. With the ratcheting hoist, I found it to be simple and did not make a mess doing so. I was able to achieve an efficiency of just slightly greater than 86%.

 

[LittleRiver]

It was posted on here a while ago that hanging the bag for the hour gets roughly halfway between an immediate draining and a good squeeze. I'm not sure how accurate that is...

I did a couple of tests with this, letting the bag gravity drain for an hour, then measuring what I could squeeze out of it. For a straight grain 5gal recipe it was about a cup. For a recipe that included a pound of flaked oats, it was about a cup and a half.

That was the last time I'll ever squeeze a bag.

 

[Cato1507]

I haven't tried it yet, but from what I have read Step Mashing is a bit more complicated with BIAB. You don't want to apply direct heat to the grain bag and adding hot water could easily throw your numbers off. I'm pretty much going to avoid it unless it's absolutely necessary.

Depends on the heat source. I added heat when i used induction cooktop with no ill effects, and since then upgraded to Blichmann ULWD boil coil and I run my heat the entire mash with the bag resting on the coil and it does not scorch or burn.

 

[Gruel]

Ok, so maybe it's more than 1%. But I squeezed nowhere near half a gallon out of that bag. If I try to measure the amount of liquid, I will for sure make a mess....

Regarding step mashes: I am doing step mashes, with a bag in a 5 gallon kettle with ~4 inches of headroom, on a 15,000 BTU/hr burner. I'm putting a heat shield between the stainless kettle and the flame (folded aluminum foil for now; I need to invest in something fancier that holds up a bit better). Even with the burner turned down to a bit over half, I find I still have to be super careful not to burn the part of the bag hanging over the edge of the kettle. In order to keep wrangling the bag to a minimum, I mash with my sparge manifold (home made slotted copper spiral for syphoning out the wort) already in place below the bag. I think this helps keeping the bag from melting to the bottom of the vessel. But my mashes take a long time because of the manual temperature control; I posted details in another thread (Konstantinos, unhappy about sour wheat beer). I don't mind though. I would just like to minimize the spillage and messiness.

 

[Nubiwan]

Conversion is not a simple thing that is done once it's done. I think this is an oft-stated half-truth among homebrewers.

First of all, at lower mash temps where beta amylase is the primary worker, conversion takes much longer than with alpha amylase at higher temps. So it's not enough to state a fixed period of time like 20 minutes for how long conversion takes. It's entirely dependent on the temperature.

It is true that all starch may be converted to sugars after a given period of time. But enzymatic activity is still occurring in the wort. A mash that drops in temperature over an hour or more experiences further breakdown by beta amylase of the long chain dextrins created by alpha amylase. In this way, a mash that cools precipitously can produce a far more fermentable wort, and hence a higher ABV end product than desired.

Beta amylase does not denature like a light switch at higher mash temps. It is a gradual process. So as the temperature drops, any beta that hasn't denatured is continuing to work.

Now in the end, none of this really matters that much unless you are aiming for a particular result in the fermentability of the wort. Mashing is really quite forgiving in the end. But this is why some brewers obsess over temperature control, and others just relax and have a homebrew.

Is there a great deal to be gained stabilizing mash temp, over letting it ebb 2-4 degrees? Any difference in taste? I say there is little evidence to suggest it does. Brulosophy experiments suggest I am correct.

 

[Ninoid]

Is there a great deal to be gained stabilizing mash temp, over letting it ebb 2-4 degrees? Any difference in taste? I say there is little evidence to suggest it does. Brulosophy experiments suggest I am correct.

I start with a temperature of 72'C so when it drops to 62'C I warm up a bit. I don’t think beer would be any better if the temperature was stable. More frequent mixing is more important.

 

[Nubiwan]

I start with a temperature of 72'C so when it drops to 62'C I warm up a bit. I don’t think beer would be any better if the temperature was stable. More frequent mixing is more important.

Why you feel more mixing important? I do it once or twice during mashes. My grains all look fairly well suspended, so I give it little further thought. Think it helps much?

 

[Ninoid]

Mixing is essential for an even temperature distribution as the temperature at the bottom is always higher than at the top of the kettle.

 

[lowtones84]

That's actually why I've been doing multi-step mashes with my BIAB. 2-3 steps usually. More mixing, more control over the fermentability and mouthfeel of the product, overall better results in my opinion when using unmalted adjuncts.

 

[hawkbox]

I've slowly converted my 3 vessel propane setup into a BIAB system and it seems to be working. It might be the most convoluted conversion out there but it seems to be working fairly well. Just need to get my math working better to take up much less shelf space.

 

[Gruel]

Math taking up too much shelf space? Is that what happens just before you run out of numbers?