I made an all-grain double IPA recently that has a pretty potent off-flavor that hits you up front. Hard to describe but kind of dank and musty. I used that new grainfather contraption and I think I may have accidentally caused hot-side oxidation; when using the counter flow wort chiller I didn't think to submerge the wort outflow end under the surface and it was probably introducing O2 as a result of this constant pouring method (yes I realize this was extremely unprofessional of me). It seems there is some controversy as to whether this type of oxidation has a significant impact or not and I was curious if anyone has experienced something similar. I find it hard to explain the flavor and I really don't know what "wet cardboard" tastes like which is frequently mentioned. Plus, it combines with all the hops to make any even more confusing sensation. Earthy, dank, musty words come to mind (clearly unpleasant, definitely not the normal hop flavors). Not sour.
Other relevant:
-recipe was similar to the pliny clone.
-s-05 (2 packs rehydrated) at 64 but did pull from the chamber a little too early. Ended at 72. Thought this was the issue at first but the flavors don't seem fruity. Also used pure O2 before pitching and have since read this is not necessary with dry yeast. Could this be an issue?
-fresh grain smelled good.
As an aside since you may be curious, the Grainfather seems solid if paired with a heat stick. The 1600W internal element is not hot enough in my experience.
Other relevant:
-recipe was similar to the pliny clone.
-s-05 (2 packs rehydrated) at 64 but did pull from the chamber a little too early. Ended at 72. Thought this was the issue at first but the flavors don't seem fruity. Also used pure O2 before pitching and have since read this is not necessary with dry yeast. Could this be an issue?
-fresh grain smelled good.
As an aside since you may be curious, the Grainfather seems solid if paired with a heat stick. The 1600W internal element is not hot enough in my experience.