I just did my first brew on my new AIO system, and am conducting a post mortem to determine what to tweak in my personal spreadsheet and BeerSmith profile. As my pre-boil volume was about 0.5 gal higher than expected, the only thing seemingly affecting that is that the grain absorption rate has decreased. To hedge my bets and prevent a clogged pump, I used a handful of rice hulls (rinsed/pre-soaked) for the and conditioned my grain (~11 lbs). I've never had an issue with rice hulls in the past in this regard, so the only thing left is the absorption.
Mill my own grain (and haven't changed the gap), and I've previously used an absorption rate of 0.50 qt/lb (0.125 gal/lb) with accurate and predictable results. However, with 0.5 gal extra pre-boil volume on my AIO, this adjusted rate is 0.38 qt/lb (0.095 gal/lb). Logic would dictate changing to an AIO and all else being equal, absorption shouldn't change. Does anyone that conditions their grain experience this decrease in absorption? I haven't found any references to this happening or why it would.
Mill my own grain (and haven't changed the gap), and I've previously used an absorption rate of 0.50 qt/lb (0.125 gal/lb) with accurate and predictable results. However, with 0.5 gal extra pre-boil volume on my AIO, this adjusted rate is 0.38 qt/lb (0.095 gal/lb). Logic would dictate changing to an AIO and all else being equal, absorption shouldn't change. Does anyone that conditions their grain experience this decrease in absorption? I haven't found any references to this happening or why it would.