Rye absorption rate.

[Dave70]

I normally allow for a rate of .9 liter per kilo of grain absorption in the mash which is generally pretty close to the mark, however both the last brews using rye from 19 to 21% seemed to have come up short on volume. Oddly the OG on both was within a point or two.
Anybody else noticed this when using rye before?

 

[brendo]

Rye has a lot of beta glucan in it and can really gum up the works at higher rates, which can affect launtering. Make sure you are getting a good mash out temp and that the grain bed isn't cooling down too much during lautering. You may also benefit from a brief beta glucanese rest (35-55 degrees) with 45 degrees considered optimal.

I have only ever needed to worry about the mash out when using rye up to 30%, but your mileage may vary depending on your system set up.

Cheers

Brendo