Dry hopping...how big of a risk is oxidization?

[crashlann]

Dry hopping my current Rye IPA last night, I was wondering how big of a risk is adding a bunch of O2 to the wort and getting oxidized flavors. I had a real problem with oxidization with my Belgian beers last year, I was adding O2 7 days into fermentation. I use the Jamil alum foil carboy cap technique, so if I give the carboy a big swirl to get the hops in solution, Im adding potential O2 (21%) to the wort. My CO2 tank was empty so I couldnt prime the carboy, but this would probably be a good technique, or is really not a big deal? Thanks.

[Ozwald]

I was adding O2 7 days into fermentation

On purpose? There's the problem... big no-no. Add O2 before pitching. If there's absolutely zero signs of fermentation you can give it another shot a few hours later, but if you see one bubble of CO2, do not add any more O2 after that point what so ever.

Once fermentation starts, it's pumping out CO2 which will purge all O2 from the headspace. Even after fermentation subsides & it's not actively pumping it out, the CO2 is still heavier than O2 so that blanket will stay there. Gently swirling shouldn't disturb that CO2 blanket too much, so you're relatively safe at that point.

[crashlann]

I was adding O2 7 days into fermentation

On purpose? There's the problem... big no-no. Add O2 before pitching. If there's absolutely zero signs of fermentation you can give it another shot a few hours later, but if you see one bubble of CO2, do not add any more O2 after that point what so ever.

Right, I learned that one the hard way. Had to drink one batch that was sub-par, and actually dumped one, both Belgian Strong Ales. I thought I was so smart adding all that O2...hahahaha...

Ok, so adding the hops shouldnt be a big deal, thanks. It hasnt been a problem so far, so I didnt think so.

Thanks again...

[Ozwald]

Err on the safe side. If you hit it with O2 prior to pitching, it's rather likely you don't need any more. Just because you can doesn't mean you should. And the tiny amount that might be trapped in your dry hops isn't anything to worry about. In the words of our beloved Ms. Talley... "Dry hop the shit out of it." Still waiting on that tee-shirt.

[brewinhard]

If you really want to try to minimize oxidation when dry - hopping, then add your dry hops into the primary fermenter when your majority of primary fermentation has slowed down. This will allow for the remaining CO2 produced to push out any oxygen introduced into the vessel. You will also scrub out some hop aroma with it so, add a bit more hops to compensate for this (if you are even that concerned about it).

[crashlann]

If you really want to try to minimize oxidation when dry - hopping, then add your dry hops into the primary fermenter when your majority of primary fermentation has slowed down. This will allow for the remaining CO2 produced to push out any oxygen introduced into the vessel. You will also scrub out some hop aroma with it so, add a bit more hops to compensate for this (if you are even that concerned about it).

Thanks Brewinhard, I do that, probably because I read you or someone else say the same thing before. I definitely have improved my since being more carefu about this. I wish I had a couple batches back from last year though...

[FedoraDave]

Interesting seminar at the AHA Convention last weekend regarding preserving hops flavor, especially aroma. The upshot I got from it is that they've discovered the aroma esters in hops are so volatile, dry hopping may be most effective if done only 24 hours before kegging or bottling, and then the beer should be chilled ASAP. Easier and more effective when kegging, obviously, since bottles need to carb and condition for a few weeks.

But it's worth keeping in the backs of our minds when we're dry hopping and really want that aroma to come out. I've been racking to a secondary after two weeks, then dry hopping for a third week before bottling. This is something of a game-changer.

[brewinhard]

Both Mitch Steele and Stan H. at their NHC conferences discussed the "synergy" effect that can happen when dry hops come in contact with suspended yeast in beer. Revealing that the combined forces of yeast with the dry hop oils can result in new aromas and flavors not gotten w/o dry hopping, or even dry hopping sans yeast present. Interesting stuff going on with lots of new research to look forward to. Gotta love the "big dogs" who dedicate their time to these sort of things!

Hmmmm.....maybe I should sell my kids and get down to some real work!