I think as a generalisation Clint you do need to leave hops in for longer than normal to get any grassy notes it is worse with pellet hops as they have a lot of crushed vegetive matter. I personally have not suffered from it and have dry hopped for upto 7 days but no longer so I do not worry too much about
My dry hopping now exclusively consists of keg hopping. They stay in the keg until it's empty. I've had them in there for 6mo on a slow drinking keg. Never got grassy notes or had any problems leaving them in contact with the beer for long periods.
As an experiment I did dry hop two beers for over a month, with pellets. I didn't get grassy notes, but I got a different kind of bitterness, somewhat like a hop tea. Also, I think this bitterness was more of a function of the hops, which I think were Magnum in one case, and a remainder of Challenger I think.
Have you ever added them to the FV then transferred to the keg? I dry hop in the FV in those nylon fruit and veg bags and have often considered putting it into the keg as well as the beer.
Really useful info thanks - are you using whole hops, and how many are you putting in the keg?
I've used whole and pellet. I do put them in a bag so they don't clog up the dip tube on the bag. I've used a half ounce up to a full ounce for IPA or APA.
