Author Topic: Why is BIAB grain absorption much lower than a tradition mash?  (Read 1624 times)

Offline EdwardGambrinus

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Why is BIAB grain absorption much lower than a tradition mash?
« on: January 10, 2017, 09:07:35 AM »
I cannot find the answer to this question.  I have found a couple of comments that indicate BIAB absorption is significantly lower, but none say WHY this is so.  Can anyone help?

Offline Oginme

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Re: Why is BIAB grain absorption much lower than a tradition mash?
« Reply #1 on: January 10, 2017, 09:47:21 AM »
Couple of reasons for this.  First, versus a traditional mash tun, there is a lot more drainage area from the grains.  Next, the compression of grains caused by lifting the bag releases some of the free water which is contained between the grain particles.  Third, many people squeeze the bag and release more of the free water from the grains within.

I use three different brewing set ups:  two of them BIAB and the third a cooler mash tun.  They each have a different grain absorption rating based upon the amount of grain and my subsequent handling practices for each.  It would be better, IMHO, to tie in the grain absorption rate to the equipment profile instead of having it as a globally set variable (hint, hint Brad).

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Offline EdwardGambrinus

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Re: Why is BIAB grain absorption much lower than a tradition mash?
« Reply #2 on: January 10, 2017, 09:59:25 AM »
Got it.  Thanks!