Rack For Biab - Any Ideas?

[the_new_darren]

I agree but the "bag" would cool slightly and then hence cool the "wort" when it was plunged back in. May need to compensate slighly higher MO temps if lifting the bag.

tnd

 

[pk.sax]

@Nick

If you read TB's post carefully, heating it all to mash out also releases the more stubborn starches from the grain.

So, yes, there is indeed a benefit in heating the sort with the grain still in it. Not to mention the standard reason of a better drain from the grain at a higher temp.

TB's post has me thinking that I will have to calculate the volume of my MT and experiment a bit to get the right grain to water ratio to promote better conversion. So far, I've been plugging in whatever is convenient.

 

[Thirsty Boy]

Thanks for the clarity on the BIAB mashout process. My process was close, but it clearly helps to understand precisely what needs to be achieved and the approximate time required to achieve it. I think that with my urn it takes about 10 minutes to get to mashout temps anyway just by turning it on, but I will be checking. Which would mean no additional time required.

So by extension, a potential fault with BIAB might be in some cases excessive starches in the boil. I should know but can't remember - too much starch can lead to haze... and what other faults?

Its a potential, but not particularly likely result - especially if you do any stepping, mid mash stirring or a longer mash.

The stirred ramp to MO temps certainly does improve your efficiency - given the same amount of liquid and the same amount of grain... the only place its coming from is extra starch conversion. Therefore there must be unconverted starch, and the potential of this starch to make it into the kettle increases because of the manhandling a BIAB mash goes through when you pull the bag, especially if you give it a squeeze.

A ramp to MO temps makes the potential issue go away - one more item ticked off the long list of small things done well, that leads to excellence.

Starches in your boil and/or beer can lead to haze and also make the beer less micrbiologically stable. Starch is bug food - beer doesn't otherwise have a lot of bug food in it.

bcp makes a point that is often overlooked, because BIAB is a single vessel process you have to heat that vessel anyway to bring to the boil. So (provided you have a rack or some means of not scorching the bag) the mashout comes for free and you'd be nuts not to do it. The only penalty is having to stir for 5 or 10 minutes.

TB, is the higher liquor to grain ratio the reason that some starches might get missed in the thinner, less intensive enzyme soup? So if there's an easy way of preparing some more liquor (in my case in a pail with the OTS heater) would there be advantages in mashing at a LG ratio more like 3V and using a quantity of hot liquor into the pot to raise to mashout temperature? Quite easy to calculate with one of the online "mixing" calculators. Maybe BS has one?

Also I thought that vorlauf was more to do with preparing the bed for sparging after the mashout?

Absolutely Bribie - you have to heat up a few kgs extra because you are including the spent grain and the liqudi that would be trapped in it ... but the majority of the time heating is time you would spend heating anyway. The effort component is the stirring. It adds maybe 5min or so to your total brewday to include the ramp to MO temps vs just pulling the bag out at final mash temp.

L:G ratio - If you recall or care to torment yourself by reading the earlier stages of the threads when BIAB was first being developed and popularised - one of the main arguments against BIAB was that the L:G ratio was too unfriendly towards enzymes. Starches wouldn't convert, if they did the worts would be too sweet because the beta amylase would all be denatured too quickly... etc etc.

It all turned out to not be an issue - BIAB works. BUT - that doesn't mean the reasoning was all wrong. BIAB is marginal - too much further down the road and you'll reach a point where things do stop working properly. So - if you are talking about resistant starches, starches that are often not converted even at more optimal L:G ratios in "normal" brewing techniques... Its my opinion that BIAB is either going to be worse, or at least no better at converting them (although that is arguable if you look closely enough) - but BIAB handles the mash roughly. Normal brewing techniques recirculate and drain through a mash bed... a mash bed that traps fine particles particualrly well. Fine particles like ungelatinised starches, protiens, bits of husk etc. You dont have that with BIAB, lots more stuff gets into the kettle.

You could, if you have the means, mash at a normal L:G and add water at the mash, just like a no-sparge brewer in the mash tun world. Works perfectly well and there is no reason why not. But - even at optimal L:G ratios, you are likely to have a percentage of unconverted starch in the mash, and the whole lack of mash bed thing simply raises its head again when you pull the bag. Converting "all" the starch is about the intensity of the mash - L:G ratio is much less important. Physical agitation, crush, time, and temperature are the important things.. a triple decoction being more or less the ultimate expression of "intense". Ultimately, I dont think you would get a perceptable quality increase (although I've not done enough brews that way to stamp my feet and insist) and would it be any less trouble than just increasing the intensity of your mash by doing the mash out ramp?

Personally, if you were going to do a low L:G BIAB and then an infusion to raise temp, I'd consider not going all the way to 78. Maybe go to 72 or 73 - that'll access all but the most stubborn starches and still leave you with plenty of alpha amylase action to convert them. If you wanted to finish at MO temps, then do another step. It just becomes bog standard infusion step mashing - nothing new to see here.

Or - just skip the temp increase and yoink the bag out at your highest mash temp.... the MO ramp is a belts and braces thing that I think's worth doing because it combines a solution to a vague potential quality issue, with higher efficiency & really very minimal added time or effort. If its too much time or effort or it streesses people out... just dont do it.

 

[iralosavic]

So if you do a over pot "sparge" (ie just rinse and allow to drain back into kettle), what type of mash out would apply and in what order would you perform each step?

 

[Thirsty Boy]

I have no idea - I'd never do that. Sorry.

At a guess - mash out first, with the stirring and the ramping.... always with the stirring and ramping! Then sparge after you have no starch left to do anything. Or - no mash out at all, a sparge will give you much better efficiency return anyway, so the biggest part of the reason to do a mashout is out the window anyway.

BTW - Dunk sparge instead, pouring water over the grain bag is about the shittiest way I can imagine to actually sparge a BIAB bag. Better yet, make your life easier and dont sparge at all - then you dont have to care.

 

[Camo1234]

WOW - This forum rocks! Ask a quick question that has been bugging you for a while and a multitude of people come running to help you out!

My question re how to do a mashout with BIAB has now been answered.... The only issue is I now have a million other things on my mind now about the mash! :huh:

I can still remember when I got my first brew kit 18 months ago and telling my fiance that it is "really simple these days"... Just tip in the tin, add some sugar and water and leave the fermenter in the garage for a few weeks! Now I have a three tap keg fridge, 3 extra fermenting fridges, half a garage full of brew gear and spend my spare time reading brewing forums! I am so glad it isn't as I first thought because I can still remember feeling a bit cheated with "how easy " the first batch was.. It tasted Shite obviously but now with a bucket load more effort (and satisfaction) I now have awesome tasting beers that surprises everyone that tastes my "home brew"!

Cheers Falles!

Camo :beer:

 

[iralosavic]

All I currently do is bring the kettle to the boil with the bag still in it, lift it out when it reaches 76-78c, hang bag over pot to drain with occasional squeezing, by the time the boil is beginning I remove the bag and chuck the grains out. So no need to modify this process then, I take it!

 

[Mikedub]

I've just Biab mashed a merican brown, I have in the past lifted the bag out while ramping up to 76 degrees, today I just used the ramp up to mashout temp constantly moving the grain bed with a paint stirrer as suggested by TB above,, I usually hit about 68% efficiency, today I hit 74%,

sweet! thanks TB and other posters here,