onion / garlic flavor in octoberfest

General Homebrew Discussion
1

Greetings All,
  I brewed up 10 gal. of octoberfest back in September.  After kegging it and letting it lager for a few weeks I detected a strong sulphury, onion / garlic flavor and aroma.  I was going to dump it but just didn’t “get around to it”. After it sat for awhile longer this off flavor seems to be dissipating.  After boiling the wort I realized I had a couple extra gallons.  I pitched Nottingham in the couple extra gallons.  The “Octoberfest Ale” doeesn’t have this off aroma / flavor.  My recipe is listed below.  One note with the yeast starter.  I originally made 2 - 1L starters with the Octoberfest blend.  The friend I brew with couldn’t brew that particular weekend so I mixed them together in a glass growler and put them in my beer cooler / keezer.  Then the week before we brewed I built up the starter.  I decanted most of the liquid from the starter so I wouldn’t add too much volume to each fermentor.  I fermented in two 6gal glass carboys.  I’m not sure if this is an ingredient issue or a process issue.  I have made this beer before but only changed the 15 minute hop addition to strisselspalt since I had it available.  I used a different hop last year and didn’t get that flavor in my beer.  Any help with this phenomenon would be appreciated.

74% Briess Bonlander Munich
26% Briess Pilsen
28.35g Yakima Magnum, boil @ 60min
28.35g Strisselspalt, boil @ 15min
6g calcium chloride, mash
2.5g gypsum, mash
15mL phosphoric acid, mash
2pkg Wyeast Octoberfest Blend into 1gal starter

Decoction mash with short rest at 122 deg F, then a rest at 146 deg F then 156 deg F then mash out at 168 deg F. Fly sparge for 1 hour.
Boil for 90 minutes.
Chill to 45 deg. F then transfer to carboys.
Pitch yeast. Ferment at 50deg. for 3 weeks then short diacetyl rest.
Transfer to kegs and crash to 35 deg F.

Cheers,
Brandon

2

I used this yeast for my Hoptoberfest this summer and it was the nastiest smelling fermentation I’ve ever smelled. My while basement smelled like eggs. The smell eventually cleared up and I didn’t notice anything off in the finished beer. The only difference I had was that I extended my D rest to almost 10 days because I dry-hopped at the same time. Maybe this strain just takes a lot longer to finish blowing off sulfur.

3

Sounds like this yeast was nutrient-deficient.  Yeast will use sulfur as the final electron acceptor instead of carbon, if it is lacking proper nutrition.  Different yeasts have different requirements too, apparently the blend was more needy or maybe it was stressed in some other way.  You might use a yeast nutrient next time, and review your temperature regimen.  Once sulfide sits around for awhile it combines with other components to give more complex smells that can’t be removed.  Sulfide itself can sometimes be blown out of beer or will mature out in some cases.

4

Thanks for the tips. Next time will be sure to use some yeast nutrients when I brew this beer.  I haven’t had this particular problem before even though I have used this yeast in the past. Perhaps it would be worth entertaining a different yeast strain.  I’ll be glad if the sulphur character dissipates so I can drink the beer instead of dumping it.

Cheers,
Brandon

5

i use this yeast for my OK/Marzen.  I pitch cool, ferment cold (for a month), and raise to room temp for a week to finish.  I keg and then lager 1 month, seems sufficient.  I think that the room temp blows off the off flavors at the right time.

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