Strange aroma in my stouts and porters

[thirstyutahn]

Hey guys I've been trying to pinpoint a problem I've been having and can't seem to figure it out so I'm looking for some help here. Ill explain further but basically I've noticed in all my stouts and porters I've had this very strange aroma. Its very hard to describe but the best I can do is say yeasty, earthy maybe a bit musty. It comes through a bit in the taste and id say muddles the flavors.

I brewed a robust Porter a while back and it has the smell and it hasn't faded, a sweet stout I brewed also has it and lastly the dry stout I just kegged has it.

Now since I noticed it in my porter and sweet stout i tried changing some things for my dry stout. I pitched a very healthy yeast starter at high krausen, had perfect temp control and ramped up the temps at the end of fermentation. I cold crashed at 35 for four-five days before kegging it(the others were bottled)

All the beers had different yeast strains, Nottingham, wlp004 and wlp028.

Any ideas here?

 

[darrenbrews]

Per Palmer's book some suggestions could be that it's not ready for consumption and needs more conditioning, or a bad yeast, but likely the first suggestion.

 

[thirstyutahn]

The Porter has been in bottles for 10 months at least. The sweet stout 4-5 id say. I don't see how it could be conditioning time with that in mind.

This really is a strange thing. All my other beers have a great aroma and fit the style nicely.

Could it be something with my water chemistry and grain bill?

It sucks too because stouts and porters are my favorite beers but they aren't coming out like I want.

 

[SwitchbackWillie]

silly question but did you try doing your primary in different containers to make sure it's not your bucket/carboy? Possibility of something being left behind and is causing you to get that taste?

 

[AgentHubcap]

What recipe were you using? Maybe try using RO water and see if it is still there?

 

[alane1]

all grain or extract?

 

[thirstyutahn]

Well they actually all fermented in different buckets and one was in a glass carboy.

The porter was eds robust Porter in the recipe section here. The sweet stout was the left hand milk stout clone also in the recipe section. The dry stout was a classic dry stout recipe. All fantastic recipes and I didn't do anything weird and my process didn't change at all.

It just boggles my mind because I have a pale ale, pumpkin beer, dipa, and an amber/red ale that I'm drinking now and all of them are very tasty and no weird aromas or off flavors. Same process, all temp controlled, all had healthy yeast starters all used the same equipment.

 

[thirstyutahn]

all grain or extract?

All grain

 

[dabeers]

Maybe oxidation? Do you avoid mixing post fermentation, use a bottling wand, etc? Oxidation taste would likely get worse with age, but wouldn't make sense only with the dark beers and not others. Maybe astringency with the dark grains? Could add the dark grains late to mash.

 

[mattd2]

I was thinking mash pH/mineral content but then came back to the fact it is more aroma than taste. What hops are you using for the dark beers/ lighter beers?

 

[cluckk]

Since it sounds like it is not in your hoppy, light colored beers but only in the dark, malty ones, and you have used an assortment of containers, I would look at the one thing common to all, but impacting each differently--water. Look at your water profile.

 

[tjBrewer]

Mash ph is the first thing to come to my mind as well. See if you can get a local water report and plug it into one of the water calculators online along with your grain bill. This will give you an approx idea of where your mash ph is and what you would need to do to correct it.

 

[alane1]

I wonder if what you're tasting/smelling is hot break.Since dark grains lower wort ph it may have an increased impact on your darker beers.Try removing it next time, smell and taste it, if it matches the description you may have found the culprit.

 

[JRems]

Are you using English hops in your stouts and porters? I find most, especially fuggles taste very earthy and musty.

 

[thirstyutahn]

Mash ph is the first thing to come to my mind as well. See if you can get a local water report and plug it into one of the water calculators online along with your grain bill. This will give you an approx idea of where your mash ph is and what you would need to do to correct it.

Lets say this whole thing is a water issue which is what I'm leaning towards. What effect would a high or a low mash Ph have on the flavor and or aroma?

I've been trying to get a detailed local water report but my city is making it very hard. I've made numerous phone calls and left voicemails and the right people wont get back to me. I'm going to try and contact a local brew pub and see if he has any info for me.

I appreciate the suggestions and help.

Also to answer a few questions I keep most if my break and hop material out of my fermenter. I also know and enjoy English style hops and its definitely not that.

I tasted my dry stout again last night and now that its cold and carbed let me try to describe what I'm tasting now. It's a bit thin. Its lacking the roasted flavors that you would expect from 1 pound of dark roasted barley. Its very muted roast wise and it definitely has that strange aroma as well.

 

[cluckk]

If you are on a civic water system they must make a water report available. Mine, in San Antonio, is a pdf download.

PH is not going to affect flavor or aroma like this, unless it is extracting something from the grains--which you'd think would effect your pales as well. Except that dark grains will lower the pH. It could be something else in the water, perhaps some metal or mineral concentration.

 

[tjBrewer]

While these don't sound like normal issues related to low ph (astringency, poor head retention and efficiency, etc) if the only beers affected are those using dark and roasted malts, it's a good place to start and an easy variable to eliminate.

You could either get some ph strips from your LHBS and adjust accordingly during your mash or send in your water (Ward labs) and get a full report. Then using a water calculator adjust your water before mashing and verify your ph using strips or a ph meter. I prefer and recommend the latter. Understanding your water chemistry can take your beers from good to great. It may or may not fix your current problem, but it is definitely a small investment that will significantly improve your beers.

 

[thirstyutahn]

Well last night I poured a glass of the dry stout and let it warm up for a bit. The strange aroma dissipated and the I could actually taste it a lot better this time. It is definitely astringent. From what you guys are saying and what I've read my mash Ph probably is the culprit. The aroma is still weird but who knows.

I just checked the gravity on a Scottish shilling beer I have fermenting and it smells super malty and delicious...no weird aromas. Strange problem I've got going on here.

Im gonna do my best to get a water report and tweak my water. Ill brew this exact dry stout recipe again without changing anything but the water. Hopefully ill get to the bottom if this.