Grassy, astringent flavor in hoppy beers

I’ve been getting this flavor in my hopped up beers that just annoys the crap out of me. It seems like all my hoppy beers taste the same. They have this astringent quality to them, like grassiness or something. There’s no citrus, grapefruit flavor. It’s been with Columbus hops on a recent batch and Centennial on a past batch. These are older hops, I should mention. They don’t smell cheesy, but is it possible this off flavor can come from old hops taht have lost their flavor/aroma attributes, but still kept their alpha acids?
I’m quite sure it’s not an infection or contamination, because non-hopped up beers are tasting fine. Oxidation maybe? Not sure how I could be introducing oxygen, but it’s possible I’m sure. To siphon the beer into the keg, that has CO2 sitting in it, I use one of those orange carboy caps and blow gently into it. From what I’ve read, those are fine to use as there is a layer of CO2 on top of the beer that protects it from oxygen you’re introducing. But I could be wrong.

Any help would be very great!



The hops could be oxidized. sometimes when the alpha acid degrades the beer can still seem just as bitter because of other compounds in the hops - this bitterness is more astringent and unpleasant than bitterness from alpha acid. your problem could be the old hops… How old are they? were they previously opened? vacuum sealed?

Yeah they were previously opened, then later vacuum sealed. It’s just odd. Can the oxidized hops even overpower the fresher hops? Because I think I’ve used a combination before and the beer still turned out weird like this.

I don’t know that this practice is contributing to your off-flavor, but I would advise against using your mouth to siphon/blow into the beer! You’re gambling there!

I would try hop pellets and see if it goes away. I had similar issues with whole hops and I don’t know why so I gave up on them all together. TO me they tasted like what a muslin bag would taste like with a grassy backup. No matter what hop I put in my Randall, I had the same issues.

I am using pellets, I should’ve mentioned that.

El Capitan, I understand what you’re saying. Problem is, it’s only on the hoppy beers. I’m brewing a batch today with fresh hops from this year, so hopefully I’ll know for sure if it’s old/stale hops in a couple weeks when I keg it up and tap it. Otherwise, I’m going to need to look elsewhere. Perhaps, the siphoning method I’m using. But plenty of other people use that method with no complaints, be hard pressed to think that’s it right away.