Weird flavors with large amounts of hops late in the boil

[Samtallica]

I'm new here but have been all grain brewing for about 5 years. I've noticed a strange phenomenon in my hoppy beers when I use a large amount of high AA american hops late in the boil. I get a strange, almost vegetable-like aroma/flavor. I know the typical response for that issue would be DMS, but I don't think that is the case here. I only get this aroma/flavor when I use a large amount of hops.

The latest beer I've had this issue with used an ounce of chinook and an ounce of falconers flight at 15, 5 and flameout/hopstand for a total of 6 ounces of hops in the last 15 minutes of the boil. This was a 5 gallon batch, which was then dry hopped with 6 more ounces of hops. I don't seem to have the issue if I use the same amount of hops in fewer/later additions. For example, if I did 3 ounces at 10 minutes and 3 ounces at flameout.

I've been experimenting with the times of my additions in pursuit of that perfect, bright, hoppy flavor I get in a lot of commercial IPAs but can't seem to replicate at home. Maybe it's a water issue? I typically brew hoppy beers with RO water and a tablespoon of gypsum added to the mash. Not ideal, I know, but water has never been my strong suit.

I feel like I'm rambling here, but any help from you guys would be great. I listen to the podcasts pretty regularly and have listened to so many of the ones that focus on hoppy beers, yet I still can't seem to get exactly what I want.

[Ozwald]

It definitely sounds like a water issue to me. Just adding a bit of gypsum isn't going to cut it using RO water. I would recommend starting with RTFP, How To Brew - I forget what chapter the water section starts with, but it's available free online.

[Samtallica]

It definitely sounds like a water issue to me. Just adding a bit of gypsum isn't going to cut it using RO water. I would recommend starting with RTFP, How To Brew - I forget what chapter the water section starts with, but it's available free online.

Thanks for the reply. I understand water could be the issue as far as me not getting the brightness I'm looking for, but why would it cause the weird, off flavor I described?

[troybinso]

Massive amounts of hops added late can give a vegetal flavor - not a dms flavor to me, more of green pepper, or a chlorophyll-green flavor. The same problem can arise from fresh (wet) hops. You are adding a lot of hops - but not an obscene amount. Maybe you are just really sensitive to this flavor. Has anyone else picked it up from your beer?

[Samtallica]

Massive amounts of hops added late can give a vegetal flavor - not a dms flavor to me, more of green pepper, or a chlorophyll-green flavor. The same problem can arise from fresh (wet) hops. You are adding a lot of hops - but not an obscene amount. Maybe you are just really sensitive to this flavor. Has anyone else picked it up from your beer?

Yes, this is definitely more of what you describe as a chlorophyll-green favor. I think I am sensitive to it because I pick it up in some commercial beers as well, although it's always in smaller, regional breweries as opposed to larger, more national breweries. Others have not noticed the issue, but most of the people that taste my beers are not as obsessed as I am. I guess I really should make friends with other local brewers and try to get feedback from them.

[TheDarkSide]

6 oz. of dry hop for a 5 gallon batch sound excessive to me. Maybe you can do 2 stages of dry hops (3 oz. when fermentation is at 90%, then 3 more oz. 5 or so days later). This is what I do with the Pliny clone, but even then it's not 6 oz. of dry hopping.

[BDawg]

+1 on the grassy flavors. This usually drops down with age.
I also agree with Oz in that it shouldn't take a tremendous amount of hops to get good late hop flavor. Do you know how much sulfate is in your water? Perhaps a touch of gypsum or epsom salts (if you are already high in calcium) would help if its low.

[Samtallica]

+1 on the grassy flavors. This usually drops down with age.
I also agree with Oz in that it shouldn't take a tremendous amount of hops to get good late hop flavor. Do you know how much sulfate is in your water? Perhaps a touch of gypsum or epsom salts (if you are already high in calcium) would help if its low.

The interesting part (and I should've added this initially) is that this was a double batch and the other beer does not have this issue. Same grain bill, same water. The only difference is the other part of the batch was hopped with cluster and willamette in the same amounts and times. I realize these are lower AA hops though, so maybe that is the difference.