Determining SRM

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I believe chapter 7 (not exactly sure of the chapter number) of Ray Daniel's: Designing Great Beers discusses this topic. From the chapter in his book, as well as skimming the link you posted, there is no easy way in doing this, well minus some expensive equipment. I would recommend Daniel's book if you don't have it already, I enjoy it.
 
I believe the calculation for final SRM below 50 is:


SRM color = 1.4922 * (MCU ** 0.659)

where

MCU = (SRM_color * Grain_weight_lbs)/Volume_gallons

(From Beersmith site)

LOV and SRM are used interchangeably I believe in beersmith
 
For an fairly accurate idea of your SRM, I think you just apply the formula and sum the contributions. You can get technical, but from what I have been reading this is akin to splitting hairs.
 
zoebisch01 said:
For an fairly accurate idea of your SRM, I think you just apply the formula and sum the contributions. You can get technical, but from what I have been reading this is akin to splitting hairs.

Thanks, thats what I ended up doing.
 
zoebisch01 said:
I believe the calculation for final SRM below 50 is:


SRM color = 1.4922 * (MCU ** 0.659)

where

MCU = (SRM_color * Grain_weight_lbs)/Volume_gallons

(From Beersmith site)

LOV and SRM are used interchangeably I believe in beersmith

Thanks, but it doesn't help because I can't figure out the algebra.

So:

SRM=1.4922 x ((SRM x lbs) / gal)
 
I actually compiled all the 'basic' (Gravities, IBU, ABV (using attenuation numbers of the yeast), SRM) stuff into an X-cel file today. Maybe I can post after some trial runs. It is mainly for estimating the recipe. It currently has space for (up to) 7 grains and (up to) 5 hop additions.
 
jcarson83 said:
Thanks, but it doesn't help because I can't figure out the algebra.

So:

SRM=1.4922 x ((SRM x lbs) / gal)

You have to take the MCU number and then raise it to 0.659 (most calculators have an x^y button)

The result is multiplied by 1.4922.
 
So lets say you have 1 lb of Crystal 30 grain in a 5 gallon batch (finished)


MCU = (SRM_color * Grain_weight_lbs)/Volume_gallons
MCU = (30*1 lb)/5 = 6

MCU**0.659
6^0.659 = 3.26

SRM = 1.4922*3.26
SRM = 4.8599

So if you put the 1 lb. Crystal 30 grain into 5 gallons of water you'd get something like 4.86 SRM. Or at least so I believe for all practical purposes this should hold. But this only works with SRM values of less than 50.
 
zoebisch01 said:
MCU = (SRM_color * Grain_weight_lbs)/Volume_gallons

Yours comes out close to what I came up with.

(Efficiency x 80% x lbs x L°)/gal

and then add 1° for brew kettle color.
Whats the 1.4922 and .659?
 
jcarson83 said:
Whats the 1.4922 and .659?


I am assuming they are correction factors resulting from experimentation. I haven't really dug down in to find out exactly. They probably did a bunch of experiments and then fit equations to the data.
 
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