I brewed a Bourbon Barrel Porter All-Grain kit from Northern Brewer yesterday, and had a strnge thing happen at least I think it was strange. I plugged the recipe into Beersmith along with my equipment profile, which Ive used before. BS told me I would need 8.57 gallons of water, total and that after mashing I would have 6.72 gallons going into the boil. I did a single infusion, medium body, batch sparge for the mash. When I was finished with the sparge, I wound up with around 7.4 gallons. To me, this would indicate that the actual grain absorption rate was a bit lower than Beersmiths default setting. Has anyone had any experience with this? Is this yet another parameter that can vary from batch to batch, grain to grain? At least with SRMs and IBUs, those are listed on the grains and bags of hops, so that you can plug the info into your recipe and modify accordingly, if need be. How can you predict absorption?
I will say, the pre-boil gravity was higher at 1.052 than the anticipated 1.050 so I was not disappointed. Im just wondering where all the extra wort came from?