adjusting for a thick mash (1qt/lb)on big beers

[SnidelyWhiplash]

I tried making an 11gal batch of 1.07 beer in a 10gal cooler, it fills right up to the rim at about .9-1 qt/gal. I took from Palmer's how to brew that a thicker mash will convert faster and less completely, making the beer maltier and lower alcohol.

can I adjust the temperature to get the same alpha/beta amylase activity? any suggestion how much? like 3 degrees would me equivalent to the 0.25 wt/lb difference?

references: http://www.howtobrew.com/section3/chapter14-6.html

 

[weirdboy]

I would not adjust the temperature whatsoever. I am not convinced that you will end up with a maltier beer from a thicker mash.


I would brew the beer at the "normal" temperature and then only adjust the recipe if the beer turns out maltier than you anticipated. Trying to adjust it beforehand just sounds like it will introduce more potential points of confusion if things don't turn out as you expect.

 

[Skipper74]

I too am not sure that you will get less conversion from the thicker mash. I brewed Biermuncher's Centennial Blonde as my first (BIAB) AG two weeks ago, which has approximately nine pounds of grain and has a projected OG of 1.040 at 70% efficiency (I am roughly estimating from memory). I was planning to mash in what I thought was a 4 gallon pot, but at the last minute I realized that it was only three gallons. To avoid a spillover, I had to remove water from the pot and ended up mashing in about 9 quarts of water (1 qt./lb.). When I measured my OG, I was shocked to see it at 1.05! I thought I may have really screwed up, but when I measured the OG the past two nights, it was steady at 1.008. Therefore, at least in my case, the thick mash does not appear to have affected the conversion or fermentability.

 

[tre9er]

I think good sparging can help when you have to mash thick. It's also said that some English beers are supposed to be mashed thick, though I can't recall why and the "science" behind it.

 

[GodsStepBrother]

I think good sparging can help when you have to mash thick. It's also said that some English beers are supposed to be mashed thick, though I can't recall why and the "science" behind it.

Thick mashes due aid in maltier beer, and more body. Some enzymes like B amylase, Proteases and a-glucosidade bond to insoluble materials in the mash, like grain husk. Thicker mashes stop enzymatic activity specifically B amylase, leaving A amylase to do most of the job which makes for larger sugar molecules that give you a maltier beer.

 

[GodsStepBrother]

When I measured my OG, I was shocked to see it at 1.05! I thought I may have really screwed up, but when I measured the OG the past two nights, it was steady at 1.008. Therefore, at least in my case, the thick mash does not appear to have affected the conversion or fermentability.

I agree it is a minor issue, and probably only works in a very narrow time frame. For example if you mash for 20 minutes then you will see the benefits of a thick mash, but if you mash for the whole 60 minutes or more, I am pretty sure there is plenty of enzymes to finish the job. This however is me theorizing, maybe someone else can add on to it.

 

[SouthBay]

1. I've never mashed for a total time less than 60 min.
2. I can't tell the difference between the same recipe mashed at 1:1 or 1:1.5 grain to water, except that the later requires less sparging.