BIAB Mash Out?

[agentbud]

I was curious if mashing out is necessary when brewing via BIAB since there typically isn't a sparge and you are going straight from mash to boil (depending how long you let it drain). I read several other posts on the subject and it seems pretty split on the subject. Whether or not you are for or against mashing out with BIAB I was wondering if there are any specific beer styles that may benefit from doing a mash out or benefit from not doing a mash out? I recently read a recipe for a belgian quad and the author said not to mash out but did not say why.

 

[wepeeler]

The consensus I see is most people skip the mash out, as it's part of the natural heating process when you go from mash temps to boil.

Heck, sometimes I even sparge with room temp water to get to volume, which drastically lowers the temp. Then just heat up to boil!

 

[hotbeer]

I think it might be more important to large scale brewing. Most of us small quantity brewers are going to boil right away anyhow.

If for some reason your wort is going to sit awhile before the boil, you might want to do a mash out.

 

[wsmith1625]

I don't do a mashout and don't find it necessary with BIAB. Did you read this thread. Check out the post from Soyben.

https://www.homebrewtalk.com/threads/biab-mashing-out.593471/

 

[MaxStout]

After the sacc rest, hoist out the bag, let it drip dry into the kettle while you bring the wort to a boil.

The advantage of BIAB is being able to simplify the mash.

 

[agentbud]

looks like most of the answers so far are regarding whether or not to mash out in general. My bigger question that I really want an answer to is if whether or not to mash out is dependent up on the style of beer being brewed. Are there some styles that may benefit (or not) from a mash out (possibly due to the types of grains being used) vs other styles?

 

[RM-MN]

The purpose of the mash out is to stop the conversion of starches to sugars. If you have your grains milled well, the conversion will be over well before you start heating the wort for the mash out. It really serves little purpose in home brewing.

 

[CascadesBrewer]

A year ago I might have send there are benefits. Beyond just stopping conversion, a mashout is reported to help with draining, boost efficiency a few points, and I have seen some stuff about impacts on body and/or head retention. I have read that the mashout step was considered more important in German brewing literature, and less so in English brewing literature.

But I stopped a bit ago and I have not really noticed a difference...other than I save a little bit of time and the hassle of monitoring the temp while I stir the grain.

 

[jtgoral]

I stopped mashing out my BIABs and I see no difference in quality. It was a waste of time from my point of view.

 

[Ninoid]

Picking up the bag instantly interrupts the conversion so there is really no need for a mash-out at BIAB. I also tried it a couple of times and didn’t see any difference in the beer.

 

[Alan Reginato]

Faster draining, because the heat lower the wort viscosity. And some extra points.

 

[DBhomebrew]

Picking up the bag instantly interrupts the conversion

Powerful bag, eh?

 

[shetc]

I do a mash out for 15 mins @ 170F. I also squeeze the BIAB bag. My experience has been that the wort seems easier to squeeze out of the spent grains after the mash out.

 

[dmtaylor]

Mash out is only useful if you can't get the wort to a boil within like 30 minutes (not a problem for most homebrewers, but in a commercial setting yes), or if the crush on your grains really sucks then that's when you'll see an efficiency bump.

I don't mash out and my average efficiency is 89%. YMMV.

 

[RM-MN]

Faster draining, because the heat lower the wort viscosity. And some extra points.

I do a mash out for 15 mins @ 170F. I also squeeze the BIAB bag. My experience has been that the wort seems easier to squeeze out of the spent grains after the mash out.

The difference in viscosity of the wort is so small as to be difficult to measure.

 

[shetc]

The difference in viscosity of the wort is so small as to be difficult to measure.

I said "seems easier", that's all.

 

[VikeMan]

The purpose of the mash out is to stop the conversion of starches to sugars. If you have your grains milled well, the conversion will be over well before you start heating the wort for the mash out. It really serves little purpose in home brewing.

Gotta disagree here. Starches may be long gone in 10 minutes or so (depending), but the longer the mash goes, the more fermentable it will become, up to (and possibly beyond) several hours. The purpose of a mash out is to stop further breakdown of unfermentable dextrins and partially fermentable sugar (maltotriose) into fermentable/more fermentable forms. In other words, to "lock in" at a desired sugar/dextrin (fermentability) profile.

I'm not arguing one way or the other for the necessity of a mashout. I do them. Lots of people don't. I suspect folks who don't do them tend to mash a little higher (or a little shorter) compared to folks who do mash out. There are several "knobs" available for influencing fermentability.

 

[RM-MN]

Starches may be long gone in 10 minutes or so (depending), but the longer the mash goes, the more fermentable it will become, up to (and possibly beyond) several hours.

My experimentation shows otherwise. With the grains milled to near flour, conversion takes less than 2 minutes and with 3 batches done with 10, 20, and 30 minute mashes, they showed no difference in the final gravity. At conversion temps the enzymes responsible for conversion do not last long.

https://byo.com/article/understanding-enzymes-homebrew-science/

 

[VikeMan]

My experimentation shows otherwise. With the grains milled to near flour, conversion takes less than 2 minutes and with 3 batches done with 10, 20, and 30 minute mashes, they showed no difference in the final gravity. At conversion temps the enzymes responsible for conversion do not last long.

https://byo.com/article/understanding-enzymes-homebrew-science/

I've read that BYO article several times in the past. Much gets made from this sentence: "This may seem trivial, but at these higher temperatures the denaturation is so rapid that the enzyme is mostly gone in less than 5 minutes." This claim is unsupported by any cited data. But even if assumed to be true, it's also quite vague. For example: What does "most" mean here? How long does it take for the portion of the enzymes that were not part of the "most" to denature? What does the denature curve look like?

I don't doubt that a fine grind speeds up the process. And it's always a race between further conversion and denaturing, but enzymes may last longer than you think at conversion temps. This has been shown by Greg Doss (Wyeast) and by Kai Troester. In the latter case, Kai found (among other things) attenuation increasing at 285 minutes (compared to 90 minutes).

http://www.homebrewersassociation.o...pdf/2012/1616-04 Attenuation - Gregg Doss.pdf
http://braukaiser.com/documents/Effects_of_mash_parameters_on_attenuation_and_efficiency.pdf
Lastly, I'll counter your experimentation with my own. I use mash length as an attenuation power knob, and it generally does what I expect, in close agreement with my software's predictions. For the record, I am not a super-fine malt grinder.

 

[MikeScott]

I still "mash out", at least when I can remember to do so. I just raise the temp to 168 and that's when I drain the bag. In reality, I forget about half the time, and I don't think it makes any difference.

 

[hottpeper13]

I do a lot of decoction mashing and it's stated in Kunze's book that after gelatinisation most of the enzymes are in the wort not the mash. So I would think you could pull the bag, heat wort to 172* and hold for a 10 min mashout. I do this as it is a dextrinizing temp to improve head retention ( also in the book)

 

[CascadesBrewer]

Below is one source of where I got some of my info on a mashout. I am not sure if Kai has any data to back up the "will lower the overall attenuation of the wort" comment. My understanding is that Alpha Amylase create a mix of simple and complex sugars. Understanding Efficiency - German brewing and more

Although mashing out or not is part of the chosen mash schedule its effect on efficiency should be discussed in more detail. Some brewers report a jump in efficiency when they perform a mash out. While this can be a result of improved lautering it is most likely the result of better conversion efficiency. If the enzymes in the mash were not able to fully convert the mash during the saccharification rest, a mash out can help the conversion efficiency by "super charging" the alpha amylase which works much faster at temperatures between 70 and 75C (158F to 167F). Above 80 C it starts to denature quickly. This super charged alpha amylase now converts the starch that has not been converted during the saccharafication rest and as a result the conversion efficiency is increased. But since the beta amylase is quickly denatured during a mash-out, the extract (i.e. efficiency) gained from a mash-out is mostly unfermentable and will lower the overall attenuation of the wort. As a result a mash-out should not be seen as a tool to increase the conversion efficiency unless the decrease in fermentability is taken into account.

Some authors contribute the extraction benefits of the mash-out to its ability to provide a temperature that gelatinizes even more starch (in particular the small starch granules which have a higher gelatinization temperature)[Scandrett, 1997]. But I have not seen a significant enough increase in the conversion efficiency by performing a mash out and many brewers report the same. While it is true that elevated temperatures will make more starch accessible, the additional amount that is made accessible in well modified modern malts is only small.

 

[RufusBrewer]

Seems to me, if there is any benefit(s) to doing a mash out step, the benefit(s): would manifest regardless of the mash and/or sparge procedure.

Until the point you lift the bag out of the kettle, all mashes will be equal. If you fly, batch or BIAB sparge the mash will produce the same results at that point in time.

I learned you do a mash out for two possible reasons. #1 To "kill" the enzymes and halt the conversion to that point and #2 heat the wort and mash because a hotter wort will have a lower viscosity and allow more wort to drain out of the grains.

#1 I was always kind of a "OK. So what?" #2 I guess I have to take somebody's word on that. When I batch sparged , getting the mash to mash out temp was not always accomplished.

Doing BIAB, a mash out takes some more time because you are heating wort and grain to 168 deg. Skipping the mash, you heat just wort to 168 deg while on your way to boiling.

So what is the science or testing data on the mash out creates thinner wort and hence more greater efficiency? As far as I can recall, I have not read or heard any evidence.