Dry Hopping Galaxy Yields Green Onion Aroma

[Scott.shuler]

I have had this happen on more than one occasion where we dry hop 4lbs of Galaxy hops (pellets) into a 7bbl batch of our double IPA. The temp of the beer is at 60 degrees. Within 2 days I pull a sample and it smells just like green onion. I have read threads dealing with hops themselves smelling like green onion, but never a dry hop yielding that aroma.

After a week most of the green onion dissipates and the galaxy pushes though, but there is a lingering aroma of onion. I do not believe I am over dryhopping, but I am apparently missing something.

Any thoughts?

[TonyT]

What crop year? yeast strain on the beer? any other hops in the beer?

I make a galaxy double IPA regularly and have never had any green onion character.

[Scott.shuler]

2014 Crop
US-05 Yeast strain
N. Brewer for bittering, Simcoe, Amarillo, and Cascade as late additions. No onion until the Galaxy addition.

[Junkyard]

You could try raising the temp up around 70 after dry hopping. It might be possible that if the green onion is dissipating with conditioning that raising temp to encourage it to volitilize. Not sure it will help at all.. Just an idea.

[AnthonyB]

Green onion / garlic / etc. is typical of mishandled/oxidized hops.

[DageraadBen]

Or it could be that you sensitized yourself to the aroma you perceived as being green onion, and then as it gradually blew off, you were able to keep smelling it because you had the aroma dialed in.

[Scott.shuler]

Green onion / garlic / etc. is typical of mishandled/oxidized hops.

My thinking was along those lines, but they came in a sealed shipment from BSG two days prior and remained sealed in the box until the time to dry hop.

[Scott.shuler]

Green onion / garlic / etc. is typical of mishandled/oxidized hops.

I seemed to have nailed down the cause of the onion, I was not present when the assistant brewers were dry hopping and come to find out they were pulverizing the hops before dry hopping. There was oxidation during the pulverizing which led to the onion/ garlic aroma. We dry hopped the next batch without pulverizing and boom, no onion.

[anthonybaraff]

Green onion / garlic / etc. is typical of mishandled/oxidized hops.

Confusingly I'm going to disagree with AnthonyB (I'm also an AnthonyB).

It has been my experience that some oxidation or aging tends to reduce onion/garlic aroma in hops. I had a lot of Columbus this year that was exceptionally garlicky. Dry-hopping with them imparted a pretty strong garlic/onion flavor and aroma. Eventually the aroma dissipated enough to package and ship the beer. By chance, I had a half-used sack that sat in my hop fridge for a month. When I smelled them again. They had reverted to the pine-citrus aroma I normally associate with Columbus. I've since used these hops and other sacks from this same lot without issue in beers. How much time passed between the first off-smelling batch of beer and the second non-onion batch? A month or months? Was the onion batch, your first brewed with that particular lot of hops?

Did someone give the hops a good sniff before adding them as dry hop? If the hops have an unpleasant aroma, I definitely would not add them to one of my beers in the future. I'd also encourage you to open the sack and store them until the aroma improves. I've compared notes with a few other brewers and some have confirmed my impression that these smells can age out of hops. Is there anyone else who has experience with this?

Anthony

[Scott.shuler]

Confusingly I'm going to disagree with AnthonyB (I'm also an AnthonyB).

It has been my experience that some oxidation or aging tends to reduce onion/garlic aroma in hops. I had a lot of Columbus this year that was exceptionally garlicky. Dry-hopping with them imparted a pretty strong garlic/onion flavor and aroma. Eventually the aroma dissipated enough to package and ship the beer. By chance, I had a half-used sack that sat in my hop fridge for a month. When I smelled them again. They had reverted to the pine-citrus aroma I normally associate with Columbus. I've since used these hops and other sacks from this same lot without issue in beers. How much time passed between the first off-smelling batch of beer and the second non-onion batch? A month or months? Was the onion batch, your first brewed with that particular lot of hops?

Did someone give the hops a good sniff before adding them as dry hop? If the hops have an unpleasant aroma, I definitely would not add them to one of my beers in the future. I'd also encourage you to open the sack and store them until the aroma improves. I've compared notes with a few other brewers and some have confirmed my impression that these smells can age out of hops. Is there anyone else who has experience with this?

Anthony

Anthony,
We all gave the hops the sniff test as we were opening them. I do not have a contract for Galaxy Hops so I have to spot buy them from BSG so they come in the 1 oz. packets (which takes awhile just to open them). I also only order them per batch so we use all of them at one time for the dry hopping. I experienced the onion/ garlic 2 batches ago (of which they pulverized the hops) before dry hopping. It was so intense that it was unmistakable. The latest batch we dry hopped (of which was not pulverized) came out very clean and crisp. Based off of the variable that was changed (pulverizing versus whole pellet) we are pretty confident my issue was the pulverization. That is not to say that the previous lot may have also been more oniony.