I believe the contact time should be sufficient to impart a nice hop character to your beer.
As I understand it you are suggesting placing the pellet hops within the hollow inner cylindrical space of your canister type water filter.
If this is indeed the case I don't believe this will work.
Placing the hops within the center of the filter will not impart the beer with hop character but rather adds the hops directly to the keg along with the beer.
As I understand it the filter works as follows. The beer in enters the plastic housing (typically blue colored) from the top and then enters the filter. It then flows through the filter comes out within the inner cylindrical space of the filter. The beer then flows upward and out for the housing and into your waiting keg or pint glass.
There should be space outside the cylindrical filter to place the hops there.
That should work though I am a bit concerned that the hop pellets will clog the filter. Even if you replace your filter canister with the coarsest mess filter available I suspect this still could be a problem especially since you are using gravity rather than CO2 to push the beer through the system.
Switching to whole hops would likely work much better in this regard. However with only the force of gravity to drive things I worry that the process may be painfully slow.
You might consider imparting hop character during dispensing with a proper Randall type system.
I used to filter my beer with a canister filter that sounds very similar to the one you have . I had some friends who were put off by cloudy beer so I used filtered my homebrew. Well I got new friends and stopped wasting my time with filtering.
The filter was sitting on the shelf for years until I came across some plans on the Maltose Falcon's webpage for making a smaller version of Dogfish Head's Randall the Enamel Animal.
I considered doing as I propose here with the whole hops and just use my filter as is. However, I decided against it simply because without the filter cleaning ups would be a breeze. Back flushing the filter with sanitizer after each use was bad enough but I never particularly liked air drying it. That always seemed like asking for trouble.
At any rate, here is the address for the Randall instructions:
http://www.maltosefalcons.com/clubgear/hash-back-aka-moormanator.
These instructions are for making a system from scratch so you will need to alter them some.
With such as system you could either use it during dispensing or run it into a keg as you proposed.
I suspect that you may be able to use hop pellets as well if you were to place some of the fine wire mess over the central stainless steel tube. It could probably be held in place with a cable tie or perhaps simply a plastic coated twist tie. For use with pellets you would also probably want to drill far more holes in than the instructions call for.
Here is what my Hop-O-Matic, as I call it, looks like:
I hope this helps
- Scott
