Sulfur Smell

My show mead is now approaching the 2/3 point (OG 1.090, current about 1.030). I degassed and fed it through the 1/3 point per hightest's recommendations. Everything seems to be going fine and it's gotten this far in 5.5 days and is still bubbling every couple seconds. Ambient temps in the ferm room have been 60-63F.

Since it reached the 1/2 mark the mead has started to throw off some sulfur smells. It's not too intense, but enough that you can smell it when you walk into the storage room where it's fermenting. I've gotten this with beer fermentation in the past, so I assume it's natural but thought I would check. Is this indicative of any problems (I'm pretty sure sanitation is fine and there is no visual evidence of any contamination)? Does this require any corrective action (degas, additional nutrients, etc.)?

Thanks for the help.

The term "show mead" describes a mead made without nutrients. If you are using nutrients, you are making a "traditional mead."

If you are making a traditional mead, and you develop sulfur odors, it is most commonly due to lack of adequate nutrients (and that can include key vitamins as well as nitrogen). It is wise to try to eliminate it sooner rather than later. The longer sulfur odors remain in the batch, the great quantity of heavier disulfides will develop and the more likely it is you will never get rid of it all.

How much nutrient (and what kinds) have you added so far?
How big is your batch?
What yeast are you using?

These are important questions to help predict how much you need.

If you are making a show mead, with no nutrient additions, dealing with sulfur odors can be difficult. This is one reason why yeast selection becomes critical for show meads. One approach you can take is to boil some other yeast (wine, bakers, or brewers) and toss that in. Since technically you are only adding more yeast, you still have a show mead (though some would say it violates the spirit of "show mead"). Another way to handle a show mead is to take the lees after racking, and keep them in another container where you aerate them repeatedly for about 48 hours. Then you toss those aerated lees batch into the batch and they will bind sulfur compounds and eliminate much of the odor. It may not be a cure-all, but it can help.

Medsen

Medsen is far more experienced than I am- but when I hear "sulfur odor" in a mead that's been fermenting, I get into a mild panic mode.

H2S will ruin a mead. In addition to Medsen's comments, I would suggest an immediate splash racking. You won't oxidize the mead (it's still fermenting) and you may fix the H2S by nipping it in the bud.

You're right, it is a traditional mead. Recipe and schedule listed below.

6 gallons
OG:1.090
2.2lbs clover honey
about 13 lbs raw wildflower honey
2 packs d47, rehydrated

Nutrients:
Wyeast Nutrient (4.4g/tsp)
DAP

At pitch (OG=1.090)
1 tsp. nutrient
1.25 tsp. DAP

At SG=1.075
2/3 tsp. nutrient
2/3+ tsp. DAP

At SG=1.060
1/3 tsp. nutrient
1/2 tsp. DAP

Must was aerated/degassed several times a day until it reached the 1/3 mark.

I think that's about it. Like I said, it seems to be doing fine and I don't want to go messing around with it if it's fine. I just went and smelled it again. I'm having a hard time describing the smell. I would say sulfury, but I wouldn't say rotten eggs. It seems to be somewhat similar to what I've smelled from hefeweizen yeast, but a little different. Not bad, but I just didn't know if I should degas again or what else should be done.

Stirring and/or racking will help blow off H2S, but you still need to eliminate the source of the problem, which is probably lack of nutrients.

Let me ask you what type of nutrient is it that you used? Does it look like tan powder or white crystals? I'm figuring you probably have less that 200 ppm YAN which is a bit on the low side. I usually like to give D47 around 250 ppm to keep it happy.

At this late stage of the fermentation it won't help to add more DAP. Late in the fermentation the yeast are not able to assimilate DAP so you have to give the yeast nitrogen in the form of amino acids. There are several ways to do that - the easiest is Fermaid O (available at midwest supply) which is a yeast extract that will provide nitrogen and essential vitamins/minerals. Adding 12-18 grams (2.5-3 tsp) to your fermentation should give it what it needs to stop producing H2S.

If you don't have Fermaid O, you can create some autolyzed yeast by boiling some bread/wine/baker's yeast (18-24 g) and that should help. Even using yeast hulls may give enough (and may bind some of the sulfur) to help it. Any of these should give it what it needs to behave itself.

I hope that helps

Medsen

The nutrient is Brewer's Choice Wyeast Nutrient Blend. According to one of the microbiologists at Wyeast it is exactly the same product as the Vintner's choice (other than the label) and is recommended for mead fermentation. Below is the description from wyeast.com. The product is a tan powder. Mfg date was 2/7/11, so it should be very fresh.

If I were to do a little stirring at this point what is my risk of oxidation? I just checked the SG and it is exactly 1.030.

Brewer's Choice™ Wyeast Nutrient Blend

Product: Supplemental nutrients for propagation & brewing

Description: A blend of vitamins, minerals, inorganic nitrogen, organic nitrogen, zinc, phosphates and other trace elements that will benefit yeast growth and complete fermentation. Additional nutrients are most valuable during yeast propagation and sluggish or stuck fermentations. Supplementing with nutrients will reduce lag time, improve viability and provide consistent attenuation rates.

Usage Rate: 1/2 tsp (2.2 Grams) per 5 gallons (19 liters) of wort.
Usage Instructions: Dissolve Wyeast Nutrient in warm water. Add solution to kettle 10-15 minutes prior to end of boil.
Stability: 1 year if stored in airtight container in a cool environment.
Packaging: Nutrients are available in 1.5 oz, 2lb. or 8 lbs. containers

chicagobrew said:

The nutrient is Brewer's Choice Wyeast Nutrient Blend. According to one of the microbiologists at Wyeast it is exactly the same product as the Vintner's choice (other than the label) and is recommended for mead fermentation. Below is the description from wyeast.com. The product is a tan powder. Mfg date was 2/7/11, so it should be very fresh.

If I were to do a little stirring at this point what is my risk of oxidation? I just checked the SG and it is exactly 1.030.

Brewer's Choice™ Wyeast Nutrient Blend

Product: Supplemental nutrients for propagation & brewing

Description: A blend of vitamins, minerals, inorganic nitrogen, organic nitrogen, zinc, phosphates and other trace elements that will benefit yeast growth and complete fermentation. Additional nutrients are most valuable during yeast propagation and sluggish or stuck fermentations. Supplementing with nutrients will reduce lag time, improve viability and provide consistent attenuation rates.

Usage Rate: 1/2 tsp (2.2 Grams) per 5 gallons (19 liters) of wort.
Usage Instructions: Dissolve Wyeast Nutrient in warm water. Add solution to kettle 10-15 minutes prior to end of boil.
Stability: 1 year if stored in airtight container in a cool environment.
Packaging: Nutrients are available in 1.5 oz, 2lb. or 8 lbs. containers

Click to expand...

I also use Wyeast Nutrient Blend.


Roger

chicagobrew said:

Brewer's Choice™ Wyeast Nutrient Blend
Description: A blend of vitamins, minerals, inorganic nitrogen, organic nitrogen, zinc, phosphates and other trace elements that will benefit yeast growth and complete fermentation.

Click to expand...

OK that gives some good info. At 1 gram per gallon the Wyeast nutrient provides about 30 ppm YAN. This means your total additions come up to about 150 ppm. That is why you have the sulfur odor. You need to bump it up.

The inorganic nitrogen listed above is DAP. Any DAP that is added now isn't really going to help as the yeast won't be able to use it efficiently and most of it will be left over to feed spoilage organism later. If you add amino nitrogen in any of the forms I mentioned previously go with the higher range that I listed.

If all you have is the Wyeast blend, I'd use it (another 3 tsp) but just be aware that is sub-optimal.

Medsen

Medsen,

How did you come up with 30ppm at 1g/gallon? Is that the rate for DAP? This is definitely not DAP. I have a bag of that and this looks completely different. This is a fine brown powder similar to what I have seen in homebrew stores labeled as nutrient. The DAP I have is a white crystal and came from morebeer.com.

I think maybe I'm going to leave this alone. We're now down to 1.024 (at 1 week) and it is still bubbling away very regularly. The smell seems to have dissipated somewhat so maybe the yeast is fairly happy. I guess this is where I just have to relax and see what happens. If it's ruined I don't know if there is anything I can do to save it now.

30 ppm number comes from the manufacturer (Wyeast) - Golddiggie tracked that down a few months ago.

DAP gives about 55 ppm at the same 1g/gal dose.

It's your mead, and you can treat it any way you like. Personally I don't like to ignore sulfur odors in the hopes they will just go away. You may get lucky. I'd give the yeast some nutrition and stir/aerate it well.

Mmmm......I just got my first taste of that sweet, sticky mead. I just racked to the first secondary at sg=1.000 and I'm happy to report that it tasted fantastic. Definitely a little hot and dry, but the honey came through as well. I didn't taste any sulfur, so I guess my concerns were a bit off. Now on to 6 months of aging, stabilizing, backsweeting, and bottling. I hope she's ready for X-mas.