Grassy/vegetal flavours in pale ale but no other styles

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Doctormcbrewdle

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I've been struggling with pales for quite some time now and think I may have finally realised it may be down to me switching from chill to no chill since. I adjust my hop schedules so ibu remains as it should and just dry hop later on (have tried keg hopping, late fermentation, post fermentation, early fermentation, all are equally as bad) and every single pale lately has been disappointing and full of weird grassy flavours rather than any dank, resinous hop character, and this is just using 1 90 minute charge of any popular US pale ale type hop.

What's getting me is I use copious amounts of low alpha noble hops in pilsners and they all end up great! That's what's really making me wonder just what the hell's going on because it just seems contradictory, what's the difference between me using 90 minute hops in a pale Vs pils and the pale always ending up terrible?

Any thoughts?
 
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MHB

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I suspect you are going to need to pull your processes apart a bit more to help find exactly what is going on.
Doing a 90 minute boil should eliminate most of the common faults but a good look at both Diacetyl and Acetaldehyde might be worthwhile.
Search through this for both and Grassy and Vegetal might give you some clues.
Mark
 

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Markbeer

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Isn't it the dry hop that's causing problems? When you chill you can use hops late and then the chilling stops the utilisation.

Dry hopping will add less fruity and resinous and adds more grassy and vegetal flavours. It's for this reason I only ever add hops late then chill. IPA all in the last 2 minutes.

I once dry hopped with hallertau. Try it and you won't do it again.
 

Doctormcbrewdle

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Thanks guys, I'll check that article out.

It may well be hop creep, or biotransformation of dry hops, yes. I'm really not sure, but why is it only happening to me? I've tried using cryo/luplin hops in small amounts to see if this would remedy but nope
 

Doctormcbrewdle

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Possibly acetaldehyde Mark(?) I'll let this current keg sit a couple months and see if it clears up. I had been using gelatin too which was making the active yeast fall out pretty quickly so possible it still had some cleaning up to do but couldn't
 

Unslaven

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Have you checked your pH, and do you know your yeast pitch rate?

Dry hopping will increase your pH, and to compound the issue, both hops and ethanol are poisonous to yeast, which can in turn cause the pH to rise if the yeast die, and are unable to maintain the pH gradient.

I had a similar issue, where my dry hopped beers were sitting around the PH 4.5 mark before dry hopping, and finishing at 4.75 after a big dry hop (8 G/pL).

Take into account that anything above PH 4.6 is not considered food safe, and bacteria can start to thrive. Also, the yeast are unable to adequately clean up any off flavours (such as diacetyl etc) caused by hop creep in that pH range (above pH 4.5), and will start to lose viability very quickly.

I'm not sure that this is 100% your issue, but if you have the means to test the pH, it may be an eye opener.
If that does turn out to be an issue, you could try pre acidifying in the kettle (knock out @ pH 4.9-5.2) or some pro brewers even acidify with the dry hop addition, although this is harder to do without the ability to properly mix or adding oxidisation issues to the problem.

There is a really great summary of all of this in the first 5 minutes of episode 217 of the Master Brewers podcast.
I would strongly suggest having a listen.

Dry Hopping & Yeast Health
 

Doctormcbrewdle

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Hmm, thanks Unslaven. That's alot to think about.

You know the more I think the more things may make sense because this seems to have all started when I also switched from carting town water in cubes to just using groundwater (we're on bore at home). I've only just started looking at my water (albeit very basically) and throwing in a couple of teaspoons acid assuming I'd be sitting somewhere around the pH 8 because of all the rock we sit on. I haven't paid to have it tested but it will leave white calcium stains on my windshield with even just one car wash without a dry so who really knows what else I might be dealing with but I'm assuming lime is a culprit, which could potentially throw our ph even higher..

You've given me something to persue, thanks so much
 

Doctormcbrewdle

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Geez man, I really think this is my issue. Like this e host says, my lagers continue to kick ass, whearas the pales are all over the place. I repitch slurry, just like they talk about so this must be it. I've got to throw this us05 and get a new one started and really ideally use a new one every time. I also assumed hops acidified beer, whearas it's actually the opposite.

It's made me rethink my entire yeast repitch schedule actually and things have just gotten a but more exxy
 
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Unslaven

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Ahh yes the old water issue. Whether it's chlorine in tap water or just the unknowns of all of minerals. I'm lucky to be on tank, but that has it's own issues.
Who knows, maybe you'll conquer it and rename your brewery 'Big Bore Brewing co' and people will be chasing your water profile for years to come.

Re pitching is it's whole own issue, but if you're trying to isolate a problem, starting with fresh yeast is a no brainer.

Ps: Master brewers is a black hole of knowledge. It blows my brain some days and I'll have to relisten to the whole episode just to go back and recap everything they say early on which I haven't even grasped the concept of yet. That episode I linked is an especially good one. Just don't start listening to them all in order because the first few go sooo deep on malt COA's and referencing mash efficiency in relation to betaglucan percentages in malt that you'll start thinking that you need a PHD to even start learning from it.

Let us know if you manage to isolate the problem. And buy a cheap pH meter. PH is so much more important in beer than the homebrew world gives it credit for. I wish there was more publicly available information and not countless posts saying that pH only matters in the mash.

Good luck.
 

MHB

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Worth reading through what Braukaiser has to say on pH to.
One point I think it’s really important to understand is that brewing is a "batch" process. Means that what you put into the fermenter depends on what you put in the kettle, depends on what you put in the mash...
The pH should be falling at every step (mash>kettle>ferment>finished beer). Apart from the additions of acid you might make the bulk of the pH lowering comes from Calcium reacting with Phosphates and forming insoluble Calcium Phosphate, it also removes Oxalates and is used by yeast in every case removing Calcium causes the pH to fall.
It is said that 50-100ppm of Ca is the minimum required. Personally I find 150ppm at the start is enough in my local water to achieve all the targets we have for Ca in the brew. It isn’t enough* to get the mash pH where I want it, that requires some acid (I prefer Lactic) but am finding that 4% Sour malt in blond and around 2-2.5% in dark beers is enough.
Mineralising and pH adjustment to sparge water is really important, I tend to treat all my water up front, then acidify sparge water if using sour malt (very small addition required just to get under pH7).
Mark

* Just salt additions will rarely get the pH lower than ~6.5pH, there simply isnt enough Phosphate available in malt.
M
 

Doctormcbrewdle

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UPDATE 1

I received my water test strips in the mail and everything (surprisingly) appears really good. pH is hovering around 6.7 (still haven't yet calibrated my meter which also came in the mail) and everything else tests good. The 1 and only thing that is off the charts is "hardness". It's at the top of the scale. Who knows what sort of hardness exactly but its a start. The strip's aren't for brewing, mainly heavy metals etc etc, just gives the basics. Fluoride was also indicated at higher than average ratio too come to think of it

My latest pale ale has been fermenting almost two weeks now using Town water, a little smb to ward off chlorine, a tadd acid to bring pH to around 5 for mash, fresh us05 and fast chill.

Time will tell how this one goes but I'm expecting good things
 

Doctormcbrewdle

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Just calibrated my meter and done a few tests.

My tap water is reading 7.2, which is alot lower than I would have assumed otherwise

A pilsner that tastes quite good on tap fo a couple of months now measures 4.9 (seems high..?)

My latest pale ale just kegging today, smelling great I might add! Made with town water and everything else overhauled at 4.4 (still high?)

I actually added more acid than I thought I'd need to the mash without a pH meter at the time, 2 teaspoons of citric, then another half teaspoon at flameout with the 200gm hop stand.
 

An Ankoù

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Isn't it the dry hop that's causing problems? When you chill you can use hops late and then the chilling stops the utilisation.

Dry hopping will add less fruity and resinous and adds more grassy and vegetal flavours. It's for this reason I only ever add hops late then chill. IPA all in the last 2 minutes.

I once dry hopped with hallertau. Try it and you won't do it again.
That's pretty much my experience, too, particularly with traditional English hops like Goldings. When I dry hop, I don't let them soak for more than 48 hours max, but I've pretty much moved over to using a hop steep at <80C.
I've noticed the same flavour in one or two commercial IPAs, too.
 

Doctormcbrewdle

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UPDATE. Just putting a pils on the mash. I threw in my 2tsp citric acid as calculated using an online resource then remembered I now had the pH meter to test. 3.6pH..! Damn. So my pale ale went in at the same, no wonder the water tasted acidic. Reminder to take anything you read online with a big grain of salt.

Funny thing is it seems to be turning out just great but will wait a few weeks before giving a proper verdict.

My pilsner, however has just been adjusted with some baking soda to 5

Over for now
 

peteru

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The pH of the water can easily be 3.6, that's not the issue. What you are interested is the pH of the mash, after about 10-15 minutes. Similarly, when you sparge, the important figure is the pH of the runnings, not the water you use for sparging.

Even small amounts of acid additions will bring plain water pH right down, since it has minimal buffering capacity.
 

Doctormcbrewdle

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True Peter. I had a finished pH (post boil) of 5.6 in the end after 165gms 3%aa Saaz

First time I've ever bothered adjusting sparge water too, always just used tap

May I ask what pH you guys are douging in at?
 

peteru

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My last brew pH values:
Mash: 5.3
Sparge last runnings: 5.6
Post boil: 5.0

I used 88% Lactic acid to adjust. 1.5mL in 14L mash and 2mL in 18L sparge.

Of course, these figures will vary with your water and with the grain bill. This particular batch had a lot of dark malts, so not much acid was required. The pale ale I brewed before this needed a lot more acid to get the pH to the right range.
 

MHB

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+1 to what peteru said.

I can’t think of a worse choice of acids than citric (well maybe Oxalic....), you would be way better off using Lactic (my go to) or Phosphoric, commercially people even use Hydrochloric and Sulphuric acids but nobody uses Citric acid.
With 88% Lactic 0.6mL/kg of grist will lower the pH by 0.1.
As a Braumeister brewer, mashing in at ambient, wait 10-20 minutes for the malt to hydrate and everything to equilibrate, take a sample close to 20oC, measure pH and add acid to need. Then start ramping up to mashing temperatures.
Most of my recipes these days include enough Sour Malt to get me very close so it’s just a fine tune to put me in the optimum pH range (5.2-5.4).
Sour Malt is standardised (at least the Weyermann one is) so that 1% of grist lowers the pH by 0.1pH.
Mark

Edit
Read up on Resitual Alkalinity.
M
 

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