Hop Astringency

[MrC]

This is a topic that I have been doing a little research on lately and trying to gain an understanding of.  I've been finding that my hoppy summer ales have a slight astringency that presents as a dryness in the mouth.  It's only subtle and not unpleasant but I would like to understand how to control it.

 

I'm confident that the astringency is not related to any other aspect of my process other than the high hopping rates relative to the body & sweetness of the beers. 

 

Is there a trick to reducing the astringency in highly hopped, light coloured beers?

Can the stringency be reduced without simply masking it with more body and/or sweetness?

 

At this stage I am planning on juggling my hop additions until I find a way around it but I would hate to think that I'm barking up the wrong tree.

 

Here's an example recipe:

http://www.forum.realbeer.co.nz/group/nzcaseswap/forum/topics/cs5-m...

 

Cheers!

 

[denimglen]

I think you should send me a sample for evaluation, two samples actually, one astringent and one not, that way I have to do a blind test ;-)

 

But yeah, kinda hard to say without tasting it.

 

I do agree with you though, light beers with a lot of hops have given me some trouble in the past with similar astringent flavours.

 

I would suggest on the next beer to taste it before dry hopping to see if that's the culprit - I've noticed this in a couple beers especially when I've dry hopped cold and I'd say this is the most likely reason.

 

I also wonder if the light beers have a slightly higher pH which may accentuate the astringency - are you doing any water adjustment?

 

And looking at that recipe that is a shitload of hop for that sort of beer, that's the amount I would use for a really hoppy pale ale.  I'd be inclined to say it's likely to happen with a hop that has a relatively low oil content, so your ratio of polyphenol-type compounds to oil would be way different to a high oil content hop like those out of the US.  Although Styrian and Motueka are both of moderate oil content so I wouldn't really point the finger at them.

[MrC]

Thanks denim.

 

Water adjustments

In that beer there were none, just filtered tap water.  Others have had up to 0.5tsp of gypsum in the mash and  two pinches of tataric acid to the sparge water (one in each pot) to keep the pH down.

 

Dry Hopping Cold

I dry hop warm (20-22C) during the second week of fermentation, then crash cool for two days and keg.  I don't rack so the dry hops are warm for 5 days and then cold for 2 days.

 

Maybe fining would help?

[Craig]

Are you sure the astringency is coming from the hops and not the malt. I've had some astringency issues, and am thinking it may be from stepped mashing where pockets of grain husks are being heated beyond 75 degrees C?  I also reckon pale lagers and ales defintely benefit from a little acidification in the sparge water.

[MrC]

I'm pretty sure the hops are the culprit. I have two beers at the moment with almost the exact grain bill, the lightly hopped beer is fine, the heavy hopped one is slightly astringent. Both beers were brewed with the same process.

Ive had grain related astringency problems in the past when I was steeping grain in too much water. It's a different kind of astringency. Hard to explain but to me the grain related astringency was a mouth puckering, sucking on a tea bag, kind of thing. What I'm getting now is more of mouth dryness. Perhaps it's just a threshold difference but they seem different to me.

[Mike Neilson]

I have read that a boil hop addition with a ph higher than 5.2 can extract hop tannins, also you boil for 30 mins before the first hop addition aye?  

[Reviled]

"you boil for 30 mins before the first hop addition aye? "

 

I don't, should I be??

[Mike Neilson]

Yip!! Theres a whole heap of technical jargon but everyone knows im no good at it but During the first 30 mins of the boil some malt astringencys latch onto proteins which are broken out during the first 30mins of the boil and are left behind in the whirlpool or kettle during after cooling and dont make it into the fermenter, howerever if you dont do this than they can latch onto hop oils and continue all the way from Boil to glass so to speak.

[Reviled]

Hmm, interesting... Might be another reason why my 60 min bittering beers are smoother than the 90 min ones...

 

So you do a 2 hour boil if you're doing a 90 min addition Mike?

[Mike Neilson]

Yip but whats the point? You will gain fuck all extra ibus out of the extra half an hour of the boil

 

[MrC]

I sometimes boil for 30 mins before adding hops and in this case I did coz it was a pils base. Didn't seem to make a difference though.

I'll take more notice of boil pH from on though.

[Mike Neilson]

Also do you add salts to your Sparge water as if you use just a couple of pinches to your sparge water it probably will do sweet f a to you mash when sparging, think Temporary and Permanant Hardness of the water

[Mark]

I've had similar flavours from similar beers, one of which I've just kegged and is almost identical in style (and hopping regime) to your beer above. It's definitely not the grainy type astringency from over sparging; it's more a peppery hotness around the mouth, not overly unpleasant but annoying none the less for your average anally retentive homebrewer.

 

Not sure what the answer to controlling it is though. It definitely shows up more in light bodied beers. Some NZ hops seem to give it more than others too - Pacific Jade (despite its low cohumulone %) seems to be a culprit. I've read somewhere that pellets can give harsher flavours due to the crushing process, maybe using whole hops would be an answer?