Sorry to resurrect an old thread. But my recent pumpkin ale is having the exact same issue. When pouring, beer fizzes up, then head dies down almost immediately, very similar to pouring a soda. Beer does seem to be carbonated based on taste and visible bubbles rising from the bottom of a "beer clean" glass. I poured a small sample into a clean jar, shook it up, and head did develop, although only temporarily again.
I brewed this same recipe a year ago (see below, different yeast) and didnt have any issues with head retention.
I carbed by turning PSI up to 30, gently rolling keg for 3 minutes. Let stand for 30 minutes. Vented, and set to 12 PSI for ~1 week at room temp. Then put in the kegerator at 12 psi, and had it in there for about a week at 38 F.
beer line is 3/8 and about 6.5 feet long. Cleaned lines and faucet with oxyclean (and rinsed with H2O) prior to putting this keg on draft.
Have poured plenty of kegs off of this tap/setup without having this issue.
I also used same brewing setup, and clean all of my equipment, kegs, beer lines with oxyclean followed by rinsing with water.
Grain bill:
1 can pumpkin in mash
7.5 lb two row
2.5 lb munich
0.5 lb C-80
0.25 lb C-60
1 tsp pumpkin spice at flameout
1 oz cluster at 60 min
yeast: had to settle for one packet US-05 (a few months past expiration) and one packet nottingham ale yeast. rehydrated and proofed prior to pitching.
Fermented at 70 for 4 weeks in primary. Finished at 1.009
Any ideas on what issue may be? The beer tastes fine, but the fizzing and lack of head retention has me puzzled and takes something away from the beer.
thanks for any help/input.