Beer body according to mash thickness

Hello my fellow brewers,

I been wondering about this topic for a couple of days now and all the info I find is contradictory.

According to BYO, thick mashing will get you a higher amount of fermentables in your wort (increasing the efficiency of your brew), because when you make a thin mash, you "cripple" Beta-amylase:

"Enzymes are more stable when they are latched onto their substrate (the substance they act upon), and a thin mash leaves a higher proportion of the enzymes floating around looking for their substrate..."

"...In any case, if you use a thinner mash, you will produce fewer fermentables than in a thicker mash (up to a point — you gotta have water to make wort!)."

Source: https://byo.com/grains/item/1604-what-mash-temperatures-create-a-sweet-or-dry-beer

But according to several other posts / web sites, thin mashing will increase your efficiency:

"A thinner mash results in better conversion efficiency, conversion efficiency being the % of total starches in the MLT being converted to sugars."

Source: http://www.brewersfriend.com/2009/03/22/mashing-thick-or-thin/

So, I'm a bit confused... What am I missing here?

Thanks for your help!

lyron said:

Hello my fellow brewers,

I been wondering about this topic for a couple of days now and all the info I find is contradictory.

According to BYO, thick mashing will get you a higher amount of fermentables in your wort (increasing the efficiency of your brew), because when you make a thin mash, you "cripple" Beta-amylase:

"Enzymes are more stable when they are latched onto their substrate (the substance they act upon), and a thin mash leaves a higher proportion of the enzymes floating around looking for their substrate..."

"...In any case, if you use a thinner mash, you will produce fewer fermentables than in a thicker mash (up to a point — you gotta have water to make wort!)."

Source: https://byo.com/grains/item/1604-what-mash-temperatures-create-a-sweet-or-dry-beer

But according to several other posts / web sites, thin mashing will increase your efficiency:

"A thinner mash results in better conversion efficiency, conversion efficiency being the % of total starches in the MLT being converted to sugars."

Source: http://www.brewersfriend.com/2009/03/22/mashing-thick-or-thin/

So, I'm a bit confused... What am I missing here?

Thanks for your help!

Click to expand...

No, I don't think you're missing anything. There is a lot of nonsense published about brewing, even by supposedly reputable sources.

Fermentability is primarily determined by your grain bill (eg. crystal/caramel malts produce more unfermentable sugars than base malts.) The second most important factor is your mash temperature. Higher temp favors less fermentable wort, and lower favors more fermentable. Mash time and crush size will also affect fermentability. Finer crush (typically used for BIAB) will gelatinize and convert quicker due to shorter diffusion distances with the finer particles. If you extend the mash times longer than needed to convert the starch into sugar, then the enzymes will chop the sugars into smaller pieces that are more fermentable (as long as the temp isn't high enough to denature the enzymes.) Mash thickness is much less significant than any of the previous variables I mentioned.

Keep doing critical reading from lots of sources, and you will eventually figure out what is good information and what is nonsense.

Brew on

I BIAB brew and use a very thin mash. My biggest problem is controlling the amount of attenuation because that very thin mash creates a very fermentable wort and even mashing high will get me a low final gravity. That says that the author of that article may not know what they are talking about. It happens frequently.

doug293cz said:

Keep doing critical reading from lots of sources, and you will eventually figure out what is good information and what is nonsense.

Click to expand...

Combine this with your own observations and experiences, and you will be able to sort through 'known truths' and universal claims more efficiently.

Thanks guys for your help,

In fact I read in some other place that mash thickness doesn't have a important play on beer body, as you guys said hehe.

I knew about the temperature effect on beer body, but no about the mash times... I always do my mash for 60 min, but I use normal crushed grain (not very fine I think) and I BIAB as well. What mash times would you guys recommend?

Thanks for everything

lyron said:

Thanks guys for your help,

In fact I read in some other place that mash thickness doesn't have a important play on beer body, as you guys said hehe.

I knew about the temperature effect on beer body, but no about the mash times... I always do my mash for 60 min, but I use normal crushed grain (not very fine I think) and I BIAB as well. What mash times would you guys recommend?

Thanks for everything

Click to expand...

The crush you have is what determines the mash time. The one hour mash is better if you have a decent crush, longer for a poor crush, and shorter for a very fine crush. I've been playing a bit with short mashes and it appears that I get the most sugars as determined by the refractometer reading at about 25 minutes but my grains are run through the Corona mill with it set as tight as I can get it. I've done a 10 minute mash and while it seemed like it was complete, it may not have been. More experimenting with that short for sure this winter.

My experience has been over several repeats of a recipe. I do BIAB, sometimes with a sparge and sometimes with full volume (time dependent choice). I cannot find much of a discernible difference in fermentability. For the same OG, the FG ends up within a point either method used.

I do get a few more points of efficiency when I do a batch sparge, but that is compensated with a little extra volume in the end.

I also do a 60 minute mash. I probably, like RM-MN has indicated, could cut back on the mash time and achieve the same result, but the 60 minutes fits well with my morning schedule and timing.