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mfalenski
05-20-2009, 09:42 AM
I made a hopped mead and when you swirl the glass I pick up slight sulfur. My girlfriend said she didn't get anything but I know it's there. It has a good aroma if not swirled though.

1/24/09
I used 16# clover honey from Sam's Club (Virginia Brand)
1 oz Cascade hops
10g EC-1118 (Proofed before pitching)
Plus nutrient additions (No DAP in this one)

Boiled 1.5 gallons water with 1 ounce hops for about 45 minutes.
Waited until that cooled to about 80 and added the honey
OG 1.095

Added 1.5 tsp yeast nutrient and 2.5 tsp yeast energizer
(I switched to Fermaid-K and DAP now, these were generic nutrient packs)

Aerated the must for about 5 minutes by shaking

Covered with cloth for 4 days, kept at about 68-70
Aerated daily over the next 4 days

Added 2 tsp nutrient 1/25/09

Added 5tsp energizer 1/28/09

Added 3 tsp nutrient @ 1/2 break

Added 1/4 tsp K Meta + 3 tsp K Sorbate @ end of fermentation

Added 1 tbsp Sparkelloid a month later 3/7/09

Racked it 3 times

Bottled 5/19/09
TG 1.012

Any thought as to where I'm getting sulfur from? Mead is crystal clear and tastes great.

Medsen Fey
05-20-2009, 10:15 AM
Well, although it appears you gave it enough in nutrients, somehow these yeast were stressed and they stalled. With a starting gravity of 1.095, using EC-1118, you should have ended bone dry with a gravity less than 0.999. Your batch stopped way short of that.

Did your rack it early?
Did you ever check the pH?
Was the carboy exposed to light (sunlight or fluorescent)?
Did you pick up any sulfur odors along the way prior to this?

mfalenski
05-21-2009, 02:11 PM
Well, although it appears you gave it enough in nutrients, somehow these yeast were stressed and they stalled. With a starting gravity of 1.095, using EC-1118, you should have ended bone dry with a gravity less than 0.999. Your batch stopped way short of that.

Did your rack it early?
Did you ever check the pH?
Was the carboy exposed to light (sunlight or fluorescent)?
Did you pick up any sulfur odors along the way prior to this?


Thanks for the reply!

I racked it to secondary after 35 days. And the racked to tertiary after adding Sparkelloid at about 58 days (after it had cleared nicely). I wanted it a bit sweeter so I added the Sorbate & meta before gravity was too low.

Did not check pH on this batch, didn't have a pH meter at that time. Now I do and check.

Yes, carboy was kept from all light.

I got no sulfur anywhere along the process. No other odors at all either. The only place I pick up anything off is when swirling in a wine glass.

I don't think I stirred the yeast back up into suspension at all on this batch, and just aerated the first 4 days until a little before 1/3 break. It did get lots of nutrient, maybe too much.

Medsen Fey
05-21-2009, 02:43 PM
Another question - is this mead bottled with crown caps or screwtop bottles?

mfalenski
05-22-2009, 09:58 AM
Another question - is this mead bottled with crown caps or screwtop bottles?

This particular one was a 12oz bottle with a crown cap. I bottled 12 in beer bottles, and corked the rest of the batch in 750ml green wine bottles.

Medsen Fey
05-22-2009, 01:06 PM
Very Interesting.

There has been debate raging through the wine industry for years about the pros and cons of different closure. One of the potential negatives about using Stelvin screw caps (ROTE closures) has been that since no oxygen get introduced to the wine, the wines may be more prone to reductive odors (sulfur smells). Some graphs taken from AWRI data (http://www.corkqc.com/currentresearch/Micro-Oxidation/AWRIClosuireRecap.pdf) show some of this; see page 5. It is also discussed HERE (http://www.wineanorak.com/closuretrial.htm).


The sensory analysis threw up some surprising results. The ROTE closure produced a rubber-like flavour/aroma in the wine after 18 months. This is unexpected and alarming, considering that the most of the Clare Valley Riesling producers decided to switch to screwcaps for the 2000 vintage, in a well publicised move. Considering that there is a long track record of bottling Riesling using screwcaps, and many library reference samples are available, it's an odd result. The authors of this paper suggest that it could be a consequence of the lack of oxygen, and that leaving a slightly higher headspace may have alleviated this anomalous result. Apart from this, no plastic-type taint was associated with any of the synthetic corks. [Note added later: Peter Godden, lead author of this trial, communicated the following by e-mail: "We are very confident that the 'rubber-like' character is not a taint, but is an unwelcome modification due to chemically reduced sulfur, as a result of lack of oxygen. However, it is certainly an important character in ROTE-closed wine, and we have highlighted its existence to avoid mass-bottling of wine under extremely anaerobic conditions which might then develop a similar character somewhere in the future. However, you can see from the other sensory data that it has not detracted from the fruit characters and intensity of aroma of the wine to a great extent so far, although the intensity seems to have increased at 21 and 24 month post-bottling testing."]


Some winemakers have made adjustments to their wines to prevent these reductive odor from developing. They may treat with copper, or use less SO2, or leave more headspace, or other stategies to make sure they don't get sulfur smells in wines bottled with screw caps. And clearly, this reductive issue does not occur with every wine (and nobody has studied meads).

I'm wondering if the sulfur note you are detecting is coming from the closure with crown caps. Since this is essentially as airtight as a ROTE/Stelvin screw cap, the same phenomenon might be occurring although it is very early. It would be easy to test - just take another crown capped bottle and see if you pick up that same smell. Then take a corked bottle and compare the two (preferably blindly with triangular tasting). You might be able to document the first (at least I think so) evidence of reductive odors with airtight closures in a mead.

I'll be most interested to hear what you find.

If the mead in corked bottles also has this sulfur note, then another possible explanation may be the hops. Fermentation conducted with hops may be more likely to produce higher level of H2S. There was a Korean Study showing this.

Effect of hops on production of hydrogen sulfide during beer fermentation. S. T. Moon (1), J. Lee (1), S. K. PARK (1). (1) Kyung Hee University, Department of Food Science and Technology, Yongin-Si, Kyungki-Do, South Korea.

The effect of hops on production of hydrogen sulfide (H(2)S) during beer fermentation was studied. Five hop varieties in conjunction with two lager yeast strains were investigated for H(2)S production using laboratory scale fermenters. Hydrogen sulfide production was continuously monitored using sulfide detecting tubes. With the exception of one hop variety (Chinook), the wort fermented by a German lager yeast in the presence of hops produced a large amount of H(2)S (32.4 g to 75.3 g). However, the wort fermented in the absence of hops (the control) produced only a total of 11.1 g H(2)S. The wort fermented in the presence of the hops by the San Francisco lager yeast strain produced much lower levels of H(2)S, ranging from 2.2 g to 25 g and 1.2 g from the control. The levels of H(2)S production seem to be strongly influenced by both the yeast strain and the levels of sulfur residue remaining on the hops. These results clearly demonstrate that hops are a contributor to H(2)S production in brewing. Accordingly, testing hops for potential risk of H(2)S spoilage problem before their purchase or production scale fermentation is recommended to reduce or prevent H(2)S production during beer fermentation.

I can't say for certain that this holds true with hops in a honey must, but it certainly raises the possibility. In any case, please do try to compare the crown cap and corked samples and let us know what you discover.

Medsen.

ken_schramm
05-25-2009, 10:21 AM
This also has the ring of yeast autolysis to me. Have a look at this (http://www.newworldwinemaker.com/articles/view?id=267). I can't say as I can readily identify the cause of the yeast's unusual performance, but sulfur compounds can result from autolysis. Judging from the recipe, I'm going with stressed out yeast from a pH crash as my best guess; they quit eating sugar and ate enough of each other to cause the sulfur nose.

I'm also curious to know the impact of 14 tsp of nutrient and energizer (1.5 + 2.5 + 2 + 5 + 3). Man, that's a ton of stuff there. Just the yeast hulls alone could be generating some off character.

Ken

Medsen Fey
05-27-2009, 09:02 AM
I went back to review "Wine Science" by Ron Jackson. Overdosing of nitrogen can lead to both incomplete fermentation and to increased H2S production by yeast. Of course it has not been studied in Meads, but it would surprise me if the same didn't hold true.

In your case, if each tsp weighs about 4 grams, I'm guessing you added somewhat more than 400 PPM nitrogen. I don't think that would constitute an overdose that should inhibit yeast function, as it falls into the range that may be optimal for yeast growth.

I'm still wondering why you the sulfur wasn't apparent before bottling.

mfalenski
05-27-2009, 11:10 AM
Very Interesting.

There has been debate raging through the wine industry for years about the pros and cons of different closure. One of the potential negatives about using Stelvin screw caps (ROTE closures) has been that since no oxygen get introduced to the wine, the wines may be more prone to reductive odors (sulfur smells). Some graphs taken from AWRI data (http://www.corkqc.com/currentresearch/Micro-Oxidation/AWRIClosuireRecap.pdf) show some of this; see page 5. It is also discussed HERE (http://www.wineanorak.com/closuretrial.htm).


Some winemakers have made adjustments to their wines to prevent these reductive odor from developing. They may treat with copper, or use less SO2, or leave more headspace, or other stategies to make sure they don't get sulfur smells in wines bottled with screw caps. And clearly, this reductive issue does not occur with every wine (and nobody has studied meads).

I'm wondering if the sulfur note you are detecting is coming from the closure with crown caps. Since this is essentially as airtight as a ROTE/Stelvin screw cap, the same phenomenon might be occurring although it is very early. It would be easy to test - just take another crown capped bottle and see if you pick up that same smell. Then take a corked bottle and compare the two (preferably blindly with triangular tasting). You might be able to document the first (at least I think so) evidence of reductive odors with airtight closures in a mead.

I'll be most interested to hear what you find.

If the mead in corked bottles also has this sulfur note, then another possible explanation may be the hops. Fermentation conducted with hops may be more likely to produce higher level of H2S. There was a Korean Study showing this.


I can't say for certain that this holds true with hops in a honey must, but it certainly raises the possibility. In any case, please do try to compare the crown cap and corked samples and let us know what you discover.

Medsen.

I will be trying them tonight. I am curious as well.

mfalenski
05-27-2009, 01:54 PM
This also has the ring of yeast autolysis to me. Have a look at this (http://www.newworldwinemaker.com/articles/view?id=267). I can't say as I can readily identify the cause of the yeast's unusual performance, but sulfur compounds can result from autolysis. Judging from the recipe, I'm going with stressed out yeast from a pH crash as my best guess; they quit eating sugar and ate enough of each other to cause the sulfur nose.

I'm also curious to know the impact of 14 tsp of nutrient and energizer (1.5 + 2.5 + 2 + 5 + 3). Man, that's a ton of stuff there. Just the yeast hulls alone could be generating some off character.

Ken

I agree with you that this batch had too much in the way of nutrient additions. I think one of my issues was that I did a nutrient addition but didn't write it down on my paper process sheet but did enter it on my computerized notes and then added more later based on the paper notes.

Some of my changes have been using an aeration stone rather than just shaking the carboy, checking and managing pH, reducing the amount of nutrients to proper levels only @ 1/3 and 1/2 breaks, basing additions on grams rather than tsp/tbsp, and re-suspending yeast every few days during fermentation. I have also changed my nutrients to DAP and Fermaid-K. I was using LD Carlson's nutrient with ammonium phosphate & urea and LD Carlson's energizer that had DAP, yeast hulls, magnesium sulphate, and Vitamin B complex.

Would checking pH now be of any value in troubleshooting?

I am going to sample another capped bottle tonight + a corked bottle to verify its present in the nose of each.

I appreciate the help you guys are giving me, GotMead.com rocks!

mfalenski
05-27-2009, 09:51 PM
pH of the finished mead is 3.35 now.

I opened another crown sealed bottle and its the same. No sulfur on nose until you
swirl it and then you pick it up. I did let a glass sit out for about 30 minutes and when I swirled it then I didnt get the sulfur.

I will try a cork sealed bottle tomorrow night.

mfalenski
06-07-2009, 09:41 PM
A little late... I opened a corked bottle tonight and it has the same slight sulfur smell that dissipates after about 15 minutes. The only thing that was different on this batch was the amount of nutrients. It doesn't taste bad nor smell funny after 10-15 minutes. Anyone want a bottle to help me troubleshoot? :)

Medsen Fey
06-07-2009, 09:55 PM
Well you've ruled out the closures, and the pH seems fine. Still, the yeast were stressed a bit as evidenced by the incomplete fermentation. That and the hops. I'm not sure why the sulfur didn't make itself apparent before bottling.

In any case, it seems you have an easy solution which is to decant before serving. Time may help this odor, and it may fade with age.

wildaho
06-08-2009, 02:38 AM
I have to agree with Medsen on this one. Decanting is your best bet without having actually tasted or smelled it. It might be that you have a particular sensitivity to "sulfur/mercaptons/phenolics/aromas etc."

But that's a good thing. You've identified something in this batch of mead that doesn't strike your fancy. If you can help identify the disagreeable note a little further, we can probably help a little better.

How do you friends perceive this mead? Do they get the same odoriferous notes that you do? Or is there some other character of the mead that strikes them more prevalently? Objective observers are a very good measure, especially when you compare how you feel about it.

One thing that really strikes me on this batch its youth. Give it a few months or a year and I think you'll be surprised at the difference.

:cheers:
Wade

mfalenski
06-11-2009, 01:51 PM
I did a full alcohol analysis on it and got the following, may not help to figure out aroma any but I think its good to know all the numbers.

ABV 11.73%
P 23.92
Real Extract 7.33 %m/m
Apparent Extract 3.45 %m/m
SG 1.01351
RDF 72.06%
ADF 85.56%
Cal 331.22 kcal/12oz
pH 3.35

mfalenski
06-11-2009, 01:54 PM
I have to agree with Medsen on this one. Decanting is your best bet without having actually tasted or smelled it. It might be that you have a particular sensitivity to "sulfur/mercaptons/phenolics/aromas etc."

But that's a good thing. You've identified something in this batch of mead that doesn't strike your fancy. If you can help identify the disagreeable note a little further, we can probably help a little better.

How do you friends perceive this mead? Do they get the same odoriferous notes that you do? Or is there some other character of the mead that strikes them more prevalently? Objective observers are a very good measure, especially when you compare how you feel about it.

One thing that really strikes me on this batch its youth. Give it a few months or a year and I think you'll be surprised at the difference.

:cheers:
Wade

I only asked one other person, and she said she didn't get anything. She's usually pretty good at getting smells right, too.

mfalenski
07-19-2009, 08:52 PM
I wanted to do a test, so I emptied half a bottle and put a T cork in and let it sit for a month, it smells wonderful. No sulfur smell whatsoever. Any thoughts?

mfalenski
03-02-2010, 12:51 PM
I made another batch with roughly the same recipe, but with much closer attention to pH and nutrient (including DAP this time.) Total nutrient was about 12g of DAP, 12g Fermaid-K in a 6 gallon batch added in a SNA fashion.

It was done fermenting by day 14. I racked on day 21 and did a taste / smell with no indication of any sulfur. However on day 35 I got the sulfur smell again after I racked for the second time. I added 2g of K-Meta, and 5g of Sorbistat-K and splashed while racking.
I also degassed after it was racked over to fully mix in the stabilizers and try to get some H2S out.

I was going to put some copper wire in today as well to help this one out. I read to aerate and leave in for about a week?

I cant help but wonder if I would have racked this sooner would it have prevented this. Can autolysis happen that fast with EC-1118?

wayneb
03-02-2010, 01:17 PM
Hmmm... could it be that you aren't smelling hydogen sulfide, but instead might be catching faint whiffs of 3-methyl-2-butene-1-thiol? That's the principal compound in a skunk's spray, and with a strong reduced sulfur component in the molecule, at very low concentrations it can be mistaken for the simpler H2S.

You are using hops in this recipe, and you had no suggestion of the odor prior to some time after the racking to a secondary carboy. EC-1118 is a notoriously neutral strain of yeast, which doesn't typically produce much in the way of reduced sulfur compounds when it autolyzes. You really haven't been on the lees long enough for much in the way of autolysis to have taken place yet, anyway.

Was this ever exposed to any sunlight, direct or indirect, while it was in that secondary? Alternatively, did you have it lit by flourescents for any period of time during that interval?

Medsen Fey
03-02-2010, 02:44 PM
It is really odd that you develop the sulfur odor so quickly after fermentation is complete given that it was racked. When you racked it for the second time was there a lot of lees? I am wondering if this is related to the hops, and if handling them differently might avoid the sulfur.

mfalenski
03-02-2010, 05:16 PM
I tried to keep this one covered while in the fermenter, it did get hit with flourescent when I was working on it, but not much. I didnt think about it being light struck though. I might put some out in the light and see what develops from that though!

There was about 1/2" lees on the bottom, it was fairly well compacted, too. I added some bentonite to this batch pre-fermentation to see how it would help in clearing.

I threw in a few grams of hops to dry hop it, or to help mask the smell if I cant get rid of it.
Taste is great, just that slight hint in the aroma thats off puting.

I might try adding some tetra hop extract to another batch to see if I can pull this one off.

It's strange though because I made four batches of this so far and the big differences were the amount of honey used and the yeast used. I used a Wyeast sweet mead yeast in one that was pretty good, and in another batch used half the honey to make a lower gravity mead. Those both were fine and were treated the same way.

Medsen Fey
03-02-2010, 05:34 PM
Well fermenting with Bentonite can definitely lead to increased H2S production. In white winemaking, some sources say not to keep it on lees that were fermented with Bentonite, so perhaps if you leave the Bentonite out all together you'd avoid the problem. Alternatively, you may need to rack it off the lees even sooner, but it is still very early to have autolysis. Was there still a lot of hop residue in the lees when you last racked it?

There'd certainly be nothing wrong with trying a different yeast with this recipe as well. D47 maybe?

mfalenski
03-04-2010, 01:05 PM
I put a piece of copper wire in & aererated it two nights ago, I noticed a drastic drop in smell last night (from a little to just a hint if youre smelling for it) I also aererated it last night just a bit. I was only going to let the copper stay in it for 3-4 days tops and then let it sit for a week and rack off of it again.

I just wanted to test the pre-fermentation Bentonite, looks like I found my answer!

There wasnt a lot of hop residue at all. I was thinking about doing this one with a D47.
Looks like I almost have to now, for research purposes! :)

AToE
03-04-2010, 01:22 PM
I could be wrong, but I think copper treatments are usually more like 10 minutes to an hour than measured in days... obviously surface area plays a big part in that though!

To be safe, you might want to take some precautions to make sure the copper precipitates out, I can't remember how that's done but someone else can probably explain it.

I don't know how much copper has to be in there to poison you, but better safe than sorry!

dr9
03-05-2010, 08:51 AM
How much stripped 24 AWG copper wire is appropriate for one gallon of sulphuric stink wine? I have about 6 miles of it.

Mfalenski, how much did you use?

mfalenski
03-05-2010, 11:24 AM
From what I've read it really seems to depend on the surface area, and the addition of ascorbic acid. I have a piece of 12 gauge wire thats just long enough to reach to the neck of my 6.5G carboy so I can pull it out easily. I've seen mention of hours to days. I removed the copper wire, so now I am going to fine it and let it sit, then use a tight filter & let that site for a while before bottling (and probably filtering again.)

I should have tested to see exactly what I am dealing with here. I was doing research and found a test where you use a copper sulfate solution, and a copper sulfate / ascorbic acid solution to determine if its a disulfide, H2S, mercaptan problem. Its still pretty early on, so I might try that to see if I can get a better handle on what may have happened.

wayneb
03-05-2010, 11:51 AM
From the behavior you observed using just the copper wire, you probably hadn't had any appreciable conversion of mercaptans to disulfides. If the reduction in stink factor is sufficient for you, but there is still a hint of it present, you can be reasonably sure that the vast majority of copper ions you introduced from the wire have reacted with the mercaptans in the presence of sulfur dioxide to produce copper sulfide (CuS). Copper sulfide is a black compound, and it is completely inert in water and alcohol, so it will precipitate to the bottom of your carboy and if you rack carefully to make sure that you don't take any of the lees layer, you can be pretty sure that most of the introduced copper will be left behind as sulfide.

Slick, huh? ;D