[tubercle]

 I haven't tried the BIB method (or whatever it is called) but you know I have to...Why? Because it's there

 Most of what I have read on here says there is lower efficency using this method due to the super thin mash.

  I know, I know, I can increase the efficency by boiling longer using the same theory that there are no stars in the lunar landing pohographs.
 
 But that, and Elvis and Bigfoot sightings aside, would there be any benefit in mashing with the full boil volume longer, say overnight?

 It seems that the longer time would allow all the enzymes to get in contact with the starch and better conversion to take place even though the mash is super thin.

  Please avoid all the usual "insulate well, stirring, avoiding oxygen, IT'S GOING TO GET INFECTED!!!" type paranoid comments. I understand those risk well.

Just asking for thoughts on conversion.
 

[EHall]

I would think your best bet is an overnight mash... my only caution is, don't let it go over 12hrs... keep it around 8-10. I've found doing overnight mashes that going over 10hrs it starts to sour.

[tubercle]

Thanks for the advise.

 Done many, many over night conversions and well aware of the souring factor.

 I was wondering about the conversion factor.

[malzig]

I'd think the thin mash would give you good efficiency.  For an average gravity beer, with near 100% conversion, I've seen 70-75% efficiency from a no-sparge beer, so I'd expect that.  You'll probably get your highest efficiency by starting the mash with half the water so that you can add the remaining half for a step in the 158-162°F range.

I think James Spencer has reported 80%+ efficiency from BIAB, but he uses a sparge step by mashing in "half" the water then moving the bag to a second pot with the other half, iirc.

[weithman5]

when i started doing smaller (1gal)batches i tried the bib idea/or a hybrid thereof.  the first time i was brewing a dopplebock.  the unexpected low efficiency (45%) made it barely a bock.  then next time  i mashed in the boil kettle, in the bag with normal mash thickness then after an hour (both mashes were only around an hour though) i lifted the bag clear and rinsed through the grain bag with the remaining water i needed. up to 60% efficiency.  i havent decided if i am happy with that or not. i hadn't thought about longer times.

[theDarkSide]

I just listened to Brad Smith's podcast on this topic yesterday and Pat Hollingdale from BIABrewer.info said he is seeing an average of 78% efficiency.

[morticaixavier]

My first AG batch was a belgian pale that I did in sort of a BIAB way. I suspended a grain bag in my bottling bucket, added my grain and mashed in with 1.25 or 1.5 qt/lb, mashed for 1 hours, drained and sparged with the rest of the water needed.

Not really the same but I got about 63% eff if I remember correctly

[Tristan]

I've always gotten 75-80% efficiency.  I infuse 2 qts/lb.  I typically stir the grain quite a bit and use direct heating to raise to mash out temp.  Then lift the bag out and pour my sparge water through the grains.  Works great.  I did a few beers this way last winter and all grain batches of starter wort.

Just a side note, if you mash for 60-90 minutes it should be enough for full conversion.  Extract conversion isn't likely to change much unless you find a good way to sparge.

[tomsawyer]

I'd think the thin mash would give you good efficiency.  For an average gravity beer, with near 100% conversion, I've seen 70-75% efficiency from a no-sparge beer, so I'd expect that.  You'll probably get your highest efficiency by starting the mash with half the water so that you can add the remaining half for a step in the 158-162°F range.

This is exactly what I've started doing, no-sparge step mash.  I average about 75%, which is just about what my efficiency was when I was batch sparging.  I do let the mash go a good 90min or so, I did a test with a single infusion at about 150F and saw things finish at about 90min.

[darkmorford]

Okay, you're gonna have to help me out here. What's BI(A)B stand for in this context?

The only time I've ever seen that acronym was when I worked in foodservice, and it meant "Bag-In-Box," as in post-mix beverage syrups. Somehow I don't see that concept working for beer.

[gordonstrong]

BIAB = Brew in a Bag.  Quite the rage in Australia.

[tomsawyer]

Based on the few times I've done BIAB I found it to be more messy and cumbersome than using a cooler MLT and doing a conventional mash.  Plus the cooler is easier to maintain temperature in, although I guess you could dip your bag in the cooler and have a decent temp that way.  Its not that BIAB is a lot harder or yields inferior products, I just don't really see a big advantage especially on a full 5gal batch.

[morticaixavier]

The big convenience factor I see in the whole aussie homebrew pantheon that BIAB comes out of is the no-chill thing but I have not heard much about that lately. It was in the same article where I read about the BIAB, BYO I think. They boild the wort then transfer directly to a sanitized 5 gallon jerry can and seal it up and wait for it to cool. If you've got the patience that seems like it might be kind of convenient. No messing around with chillers. Don't know what it would mean for DMS though

[tubercle]

 I didn't mean to start a whole thread on the entire BIAB system again

 If I ever get around to doing this it probably will only be once because my cooler system is where I want it. And, like Denny, I don'y really care to be lifting a heavy bag of wet grain.

 I was just wondering about the claims of lower effenciency in the thinner mash and how to improve on that for the benifit of those that use this method regularly. My original thinking was that the enzymes are wandering around aimlessly and don't have the opportunity to come in contact with the starch as in a "normal" mash ratio.

 It just seems that longer mash times would be more favorable to conversion by giving the enzymes more time to saturate the entire enviroment better.

[tomsawyer]

I was just wondering about the claims of lower effenciency in the thinner mash and how to improve on that for the benifit of those that use this method regularly. My original thinking was that the enzymes are wandering around aimlessly and don't have the opportunity to come in contact with the starch as in a "normal" mash ratio.

 It just seems that longer mash times would be more favorable to conversion by giving the enzymes more time to saturate the entire enviroment better.

I think the dogma that a dilute mash results in lower efficiency has been disproven in recent years.  Maybe its because our modern malts are so enzyme rich that we may have the same enzyme concentration at 3+qt/lb that used to exist only at 1.5qt/lb.  Plus you have less product inhibition in a more dilute wort, meaning lower sugar conecentrations don't cause the enzymes to slow.