oxidation problems when dry hopping

[Queequeg]

Though hop polyphenols are naturally unstable, there stability significantly decreases with DO so they are definitely interrelated.

For my ipa's I keep DO as low as possible AND I keg hop.

I am also considering a hop randelizer

 

[marjen]

Wondering to the original poster and anyone else having this problem if you are doing all grain or extract brewing?

When I first started brewing a couple months ago I made 2 extract batches. Both tasted ok when first legged but very quickly turned a brownish color and started tasting weird.

I have since made 4 all grain batches. All four tasted great and have held up fine in the keg until they were kicked, which has been 2-3 weeks so far.

Not saying it is the issue, but the rest of my process stayed the same. I dry hop during active formation and do closed transfers via CO2. So might be something to consider.

 

[malhal]

I think we've established the larger than usual amount of raw dry-hop particulate goes off because of contact with air, just like a cut apple exposed to air does. The question is how to prevent air at the bottling stage? Is it the auto-syphon that is bubbling in air or is it just the air in bottle headroom. Could any of these fix it? Switching from auto-syphon back to regular syphon, purging bottles, using anti-oxidation bottle caps, filling to brim of bottles, using plastic bottles squeezed and filled to brim which regain shape during conditioning. Or just forget dry-hopping and put all the hops in the hop-stand and stand for longer to get all the flavour in (i.e. cooked hops that won't go bad).

 

[malhal]

My problem was I didn’t have a mesh filter over the syphon inside the fermentor so some hop matter got in the bottles and ruined it.

 

[IslandLizard]

My problem was I didn’t have a mesh filter over the syphon inside the fermentor so some hop matter got in the bottles and ruined it.

Haven't the hop particles settled on the bottom of the bottles? Just pour slowly, steadily, and carefully without any glugging, then tilt back quickly when sediment starts to reach the shoulder. If the hop bits are still suspended, just pour your beer through a fine mesh strainer. No shame in that.

When racking:

• Use one of those inverter tippies on the bottom of your siphon.
• Don't stick the siphon all the way down on the bottom.
• Start siphoning from the middle, between the bottom and the beer level.
• In a bucket, a siphon clamp can help keeping your siphon along the side at the same time.
• Then lower the siphon slowly as the beer level drops.
• When about a gallon is left, slowly tilt the fermentor toward the siphon so you keep a relatively deep well to siphon beer from.
• When the beer level drops close to the trub, or any trub starts to get sucked up, quickly pull the end of the hose out of the receiving vessel to stop the siphon.