BIAB, why mashout?

[stux]

FWIW, I wouldn't raise the bag before mashout. It's only going to cool and then drop your mash temperature when you add it back. The best way is to simply agitate the mash as you heat

It's not extract solubility that you care about, but decreased wort viscosity. Ramping through all the enzyme ranges does seem beneficial too.

 

[Parkinson1963]

http://chestofbooks.com/food/science/Experimental-Cookery/Solubility-Of-Maltose-In-Water-gillis.html

Looking at the link shows that by going from 66c Mash temp to mash out temp of 76c you gain ~30% increase in solubility, thus increasing the amount of maltose that the water will hold and subsequently drain into the kettle. Any way as previously stated as you are heating to a boil anyway, lifting the bag out at 76c to gain a gravity points seems like a no brainier to me. YMMV

 

[bovineblitz]

I don't think a mashout accomplishes anything as far as efficiency goes. Theoretically you can provide reasons it should, but in the real world I don't think it does anything.

 

[MalFet]

http://chestofbooks.com/food/science/Experimental-Cookery/Solubility-Of-Maltose-In-Water-gillis.html

Looking at the link shows that by going from 66c Mash temp to mash out temp of 76c you gain ~30% increase in solubility, thus increasing the amount of maltose that the water will hold and subsequently drain into the kettle. Any way as previously stated as you are heating to a boil anyway, lifting the bag out at 76c to gain a gravity points seems like a no brainier to me. YMMV

Sure, nobody's doubting that solubility goes up with increased temperature; the question is, does it matter? By your chart, a liter of water can hold two thousand grams of maltose. For comparisons sake, a big IIPA will have less than one hundred grams of malt sugars per liter. If solubility isn't a limiting factor, raising it won't change anything.

 

[Grumpybumpy]

FWIW I always double crush my grains for BIAB and come out with great efficiency without mashing out. I am a bag squeezer though

 

[ultravista]

What is the purpose of stopping enzymatic activity to prevent further conversion of starches to sugars? Wouldn't you want more conversion than less? Does further conversion result in a higher gravity or greater efficiency?

I don't understand the importance of stopping the conversion. What are the bad results of not stopping it?

 

[bovineblitz]

What is the purpose of stopping enzymatic activity to prevent further conversion of starches to sugars? Wouldn't you want more conversion than less? Does further conversion result in a higher gravity or greater efficiency?

I don't understand the importance of stopping the conversion. What are the bad results of not stopping it?

It can result in a higher final gravity, that's about it. There won't be much to convert at that point though so it's really not going to do much.

Realistically there's no real benefit. I never do a mash out.

 

[ultravista]

I do a modified BIAB, actually mash in a bag, and either batch or dunk sparge. My numbers have always been good. Usually my batch/dunk temp is 168 to 170 anyhow so I guess that's a form of mashout.

 

[tknice]

It can result in a higher final gravity, that's about it. There won't be much to convert at that point though so it's really not going to do much.

Realistically there's no real benefit. I never do a mash out.

+1

Yes, the way I look at efficiency in general is more about dialing in your system to know how much grain is required to hit the target gravity. Higher efficiency means less grain (and possibly DME) is required.

So whether you do a mashout or not, I think it comes down to getting consistant results out of your system, regardless of how you do it.

 

[tennesseean_87]

It can result in a higher final gravity, that's about it. There won't be much to convert at that point though so it's really not going to do much.

Realistically there's no real benefit. I never do a mash out.

My understanding (someone correct me if I'm wrong), which reading the mashing theory wiki page did not contradict, is that once the starch is converted into sugars (at a certain ratio of fermentable to unfermentable sugars), continued enzymatic activity can continue to break down the unfermentable sugars into fermentable sugars. The article does state that time affects the level of fermentability (ratio of ferm:unferm sugars) because

A longer mash will give the enzymes more time to break down starch and dextrines

(emphasis mine). You seem to be indicating that once a starch is converted, it's either fermentable or unfermentable and will stay that way, while the article seems to indicate that the sugars can be further broken down, in which case a mashout would help if you are going to do a sparge or pause between mash and boil and want a higher amount of dextrines. But if you are going to begin the boil immediately (no-sparge BIAB), as you said it has no effect.

 

[bovineblitz]

My understanding (someone correct me if I'm wrong), which reading the mashing theory wiki page did not contradict, is that once the starch is converted into sugars (at a certain ratio of fermentable to unfermentable sugars), continued enzymatic activity can continue to break down the unfermentable sugars into fermentable sugars. The article does state that time affects the level of fermentability (ratio of ferm:unferm sugars) because (emphasis mine). You seem to be indicating that once a starch is converted, it's either fermentable or unfermentable and will stay that way, while the article seems to indicate that the sugars can be further broken down, in which case a mashout would help if you are going to do a sparge or pause between mash and boil and want a higher amount of dextrines. But if you are going to begin the boil immediately (no-sparge BIAB), as you said it has no effect.

It depends mainly on the starches. You might get another 1-2% more conversion from a longer mash, but I've mashed overnight for 8+ hours and only got 1% more conversion than I do when I mash for 45-60min. That's really not even proof that it's better, I've done it twice and gotten 1% more than expected both times... but sometimes I get 1% more than expected with a regular mash too.

Lately people are realizing that the vast majority of mash efficiency is gained in the first 30min of the mash. It used to be people thought that mashing longer led to better efficiency, but that perception is changing. In some cases I've done 30min mashes and hit all my numbers.

Perhaps in a bigger setting (craft brewery) time makes more of a difference due to the huge increase in volume of the mash, but at least on the homebrewing scale I've seen nothing to convince me.

 

[tennesseean_87]

I'm not talking about the efficiency, which I don't think would be affected, but about the fermentability of the wort. As the wort sits for longer, more dextrines are broken down into fermentable sugars. This doesn't change the OG, but FG, because it's changing the fermentability of the sugars (dextrines) which have already been converted from starch. That's the theory, but I've not experimented with it. I'm trying to keep as many things constant as possible.

 

[bovineblitz]

I'm not talking about the efficiency, which I don't think would be affected, but about the fermentability of the wort. As the wort sits for longer, more dextrines are broken down into fermentable sugars. This doesn't change the OG, but FG, because it's changing the fermentability of the sugars (dextrines) which have already been converted from starch. That's the theory, but I've not experimented with it. I'm trying to keep as many things constant as possible.

Yeah that's the theory. I haven't seen much of a difference between a 30min mash and a 8 hour mash when it comes to finishing gravities. If it does make a difference, it's very minor.