Stinky Batch?

[JayZeus]

I'm concerned about my latest brew. I don't have the gravity readings handy at the moment but the ABV was a little higher than intended (4.9 instead of 4.5, my point being, fermentation was finished) Oddly enough, this batch also smells off. There were no visible signs of infection and it's not a sulfur smell. It's kind of stinky like a fart but mild. I've heard the term "Baby Turtle Farts" from a homebrewing youtube video (can't remember which one) and that description actually came to mind when I smelled it. It's not "offensive" but it's not nice either.
Unfortunately, the "smell" is present in the finish but it hasn't carbonated yet. (I just racked it last night) Any ideas what's happening here?
TIA

 

[marc1]

Could it be yeast related? Maybe some time for them to drop out will help.

Regardless, a couple weeks of carbonation and refrigeration generally improves beer quite a bit.

 

[mattman91]

I had a Hefeweizen do that last year. Lasted for about a week. By the time I was finished carbonating (about 10 days in the keg) it cleared up. The poster above is probably spot on, probably a yeast thing. Give it a week or so and see if it goes away.

 

[IslandLizard]

All grain or extract?
If you can, please post your (recipe) ingredients and the yeast you used.
What kind of water did you use?
What were your fermentation temps of both of these batches?
What kind of fermentation vessel?

As to the farty odor, DMS (DimethylSulfide) comes to mind, often associated with cooked corn, cabbage, broccoli, shrimp, etc.
This is different from "sulphury" caused by H2S, which is a (rotten) egg smell.

 

[JayZeus]

All grain or extract?

All Grain

If you can, please post your (recipe) ingredients and the yeast you used.

I'm happy to do that but I think I may have figured out the problem. I'm such a newb... I think I screwed up. Quick question: In terms of calculating your ABV: When "exactly" is the appropriate time to take your OG reading? After the mash, but before the boil and hop addition?

 

[marc1]

All Grain

I'm happy to do that but I think I may have figured out the problem. I'm such a newb... I think I screwed up. Quick question: In terms of calculating your ABV: When "exactly" is the appropriate time to take your OG reading? After the mash, but before the boil and hop addition?

After chilling after the end of the boil.

 

[IslandLizard]

When "exactly" is the appropriate time to take your OG reading?

The OG reading is typically of the wort in your fermenter, to which you add yeast.

You could take a reading of the chilled wort in your kettle, as long as it is homogenized and you don't add water or fermentables to it after taking the sample.
In short, you need to get the gravity of a sample representative of what you are fermenting.

 

[JayZeus]

Alright, if that is the case then my concerns of screwing up were unjustified.

@IslandLizard Here is the recipe
4.75 lbs Weyermann Barke Pilsner
4.75 lb Rahr White Wheat
1 oz Crystal (60 min)

The target OG is 1.045 but I hit 1.048 (after the boil)
I pitched with a packet of Safale US - 05
The recipe does not specify a target FG, they just give the ABV of 4.4%

My OG was taken with a refractometer (1.048)
My FG was with a hygrometer (1.010 @ 65°)
So I'm figuring my ABV at 4.99% (Had my OG been 1.045 I'd be at 4.59%)

My source water is RO/DI with salt additions (I can list that if you like but I just went with "Balanced Profile II" from brewersfriend)

The fermentation vessel was a 6gal Ale Pale (new and sanitized) and the temps were mainly 65° (but ranged from 63° to 68°)

 

[IslandLizard]

@IslandLizard Here is the recipe
4.75 lbs Weyermann Barke Pilsner
4.75 lb Rahr White Wheat
1 oz Crystal (60 min)

Recipe looks fine.
Is that "Flaked" (raw) Wheat or Wheat malt?

Your OG being a bit higher (or lower) than the recipe's prediction has much to do with brewhouse efficiency (BHE). Many recipes are set for 75% BHE, but actual efficiencies can vary widely. At homebrewing level BH efficiency can be easily 80-85% if all the factors are optimized, anywhere from milling (fineness) to transferring to the fermenter (wort losses). A few points off either way won't make a huge difference in the final beer, you'd be hard pushed to taste those small differences in a homebrew, even if they're as high as 8% off target. E.g. 1.046 vs. 1.050 or 1.054 vs. 1.050.
But we like to have good (optimal) efficiency, as that means more beer and/or more alcohol for the same cost and effort.

Your water source and treatment should be very fine, not a reason for off flavors. Neither is your fermentation, it's pretty much right in the "sweet" middle of the temp range for the yeast used.

How long did you boil the wort? How vigorously, judging by your boil off volume?

If the offending smell is indeed due to DMS it could be from boiling too shortly. It's recommended to boil wort made with Pilsner malts for 90 minutes to drive off most DMS, 60' for all other malts. A good simmer (surface rippling) is plenty, doesn't need to be a wild rolling boil, splashing all over. At homebrew level, for a 5-6 gallon batch, a gallon an hour boil-off is a good target.

 

[JayZeus]

I'm 90% certain it was malted... it came as a kit, I didn't pay much attention... I was more focused on the mash temp.
The boil was 60 min, as per the recipe. Is it okay to share a link? (Not sure if that's breaking a rule)
The boil was gentle (between simmer and rolling)
I didn't make note of the boil off (I'll start including that in my logs!) But the final yield was about 5.5 gallons. (Had to ditch a little as it wouldn't fit in the corny keg)

 

[IslandLizard]

Is it okay to share a link? (Not sure if that's breaking a rule)

Yes, you may share the recipe or a link to the recipe here.
It's not breaking any rules as long as it's within proper context, cloning recipes, troubleshooting, inspiration, etc.

Boil may have been a little short for Pilsner malt, so it could well be leftover DMS you're smelling. Hard to tell from a distance. Any beer judges, homebrew clubs, or homebrew club members around you can ask for an opinion? How about the store you got the recipe/kit from?

There are many homebrewers who boil Pilsner malt based worts for only 60' without having DMS trouble, but everyone's process, ingredients, and taste buds are somewhat different.

 

[JayZeus]

How's this?

 

[hotbeer]

If you left it in the FV long enough to get to it's actual FG and not just hit the FG of the recipe and then a few extra days for weird aroma's and tastes to get taken care of, then don't be so worried. Just wait till you try a bottle.

After you know that it's bad, then is the time to worry and figure out what might have been done wrong so your next batch will be better.

US-05 is a pretty clean tasting Ale yeast. But I don't know what it might do if you let your ferment temps stay very high for too long. My normal fermentation temp with US-05 is 69°F and for bottles carbonating, 73-74°F

I've never had offensively bad smells come from the fermenter with it. But I have had smells I wouldn't want in my beer come from it.

 

[JayZeus]

Just a follow up. It's been about a week and the smell AND taste is gone!

There does seem to be a carbonation issue but I think that warrants a new thread.

Cheers!