This is what I ended up sending:
We met a few weeks back when you came to the meeting at Cross Street Irregulars homebrew club. I really enjoyed meeting you and your son and wanted to tell you I am really impressed with your brewery's story. Further, I think you guys have a great brand and from what is sounds like, a really special brewery and farm.
At the risk of giving an unsolicited opinion, I wanted to give some feedback on the beer itself, and didn't think the brew club meeting was the best venue. I didn't take specific notes, but was picking up some pretty significant off-flavors, most of which seemed to be from either yeast pitch rate, yeast health, or fermentation temperature.
Not having the beer to taste, I cannot specifically recall what compounds are present, nor what processes in the brewhouse might have caused them, but I seem to recall diacetyl and potentially some acetaldehyde. However, you might want to consider putting a small tasting panel together and doing a blind triangle tasting (one sample with your beer, the other two with another commercially-made example of the same beer style, such as Sierra Nevada Pale Ale next to your Tavern Pale Ale, assuming the latter is an American-style Pale Ale). After the tasting notes are complete and compared, you may be able to trace it back to a process.
You could probably solicit some local homebrew clubs to see if they have any judges available who would be willing to assist. I do have my BJCP certification, but am awaiting my final score on my written exam to see if I achieved a score high enough for 'National' level. Further, I am moving out of the area in about 6 weeks for work, so will likely be quite busy!
In any event, I debated whether to send this email and give you guys feedback, but thought I would offer my opinion. Worst-case, you can completely ignore me and hopefully be no worse off. Maybe you are already doing quality control or are aware of the problem. Maybe you just don't want any feedback, which, again, is understandable.
Best of luck to you all-