I have never experienced the described “grassy” or “vegetal” off-flavors from dry hopping before. But I think I may have it on my hands with my current batch.
I used 3 oz pellets in secondary at 55* for 8 days. I was moderately satisfied with the aroma at that point so I kegged.
It’s been kegged and carbed for one week and it definitely has an off-flavor that is not the desired fresh, floral, citrus effect. I suppose vegetal would fit. It sure was not there pre-dry hop.
I’m a little surprised it would happen with just an 8 day dry hop.
So my question is whether I can hope for it to fade, and if so, any first-hand experience in how long that might take?