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plaztikjezuz
05-24-2007, 01:10 AM
i made a strawberry melomel.

3# honey
3# strawberries (fresh)
1 1/2 tsnp fermax
1/16 tspn grape tannin
1/4 tspn acid blend
1 gallon of water
5 grams of red star Montrachet yeast
1 tspn fruit pectin

let it sit for 36 hours pitched the yeast and oxygenated every 8 hours for 2 days

I transfered the mead and it smelled like a nasty egg fart (sulfur). what can i do to get rid of the sulfur smell.
also anyone have an idea of why it produced this smell? i have made a lot of mead and 100 times that beer and never had a sulfur smell like this.
i did not take a beginning brix but it is at .998 now so it is done.
the mead did sit in the primary for 3 weeks with the fruit and i was thinking that may be my culprit?

any suggestions as to why and any advice for removing the smell. i do make beer and have a co2 set up and a carbonation stone and was thinking of bubbling co2 through the mead to scrub the sulfur out but i know i will scrub everything else also.

thanks.
scotto

ps. what does JOA mean?

beninak
05-24-2007, 02:37 AM
no clue about the sulfur, but I think u mean JAO (Joe's Ancient Orange) prolly the most popular recipe here because its so simple, and uses bread yeast. I think you can find it in the recipes section.

Oskaar
05-24-2007, 03:32 AM
How did you rehydrate your yeast, and did you take a pH before inoculating your must?

Acid additions up front are largely unnecessary with mead, especially with fruit that carries plenty of acid (like some types of strawberries). Did you stir your must during fermentation, or at least punch the cap down to keep the fruit as submerged in the fermenting must as much as possible?

Take some time to consider what you did during your ferment and then ask some more questions.

Cheers,

Oskaar

plaztikjezuz
05-24-2007, 11:24 AM
I did rehydrate the yeast, something i always do do with dry yeast, beer or wine.
I did not take a ph reading, which is hind sight i could have very easily since i have one of those hanna checker 1 pH meters, what should my pH be at, i am making a mango melomel and i have not pitched the yeast yet so i am woulndering what it should be.

i am aware that up front acid additions are unnecessary, but i am cloning a recipe i made about 4 years ago, when i did not know that and i really wanted to get it excatly like i made it before (or as close as possible) and this recipe had a tspn of acid blend for 4 gallons.

as for the fruit, i cleaned it, removed the green top and the core that is under the top, then cut them in to little peices, quarted the fruit is what i mean, put it into a corse straining bag. i did punch the fruit cap down daily something i do with all real fruit fermented beverages (mead, beer, & wine)the bag di kind prevent it from forming a fruit cap like i have seen in the past when i did not use the straing bag this small (usually use the jumbo ones).

i did stir during the fermentation and oxygenated (direct o2 with a stone and tank) for 2-3 days every 8 hours. the fermentatio was a bit cooler then normal. i have recently (about 2 yrs now) started doing cooler fermentations and i know most beer yeast that ferment down in the lower temp range produce more sulfur but i do not think the 65F is that cold?

now i see this in your post your directed me to:


“you gotta rack this off the lees and trub right away because letting your mead sit on the lees is baaaad!” That’s a load of hooey, as this recipe and others I have posted will prove to you.


my melomel did sit in the lee and trub for 3-4 weeks and i was thinking this could have something to do with the sulfur? but i have never heard of sulfur be produced by trub in beer but that is protien and not fruit fiber. so who know?
i will tell you from my experiences making beer leaving you beer on the yeast cake for months can lead to autolysis which is a nasty flavor and those flavor can be sulfur. now the one thing that i did do that was different was i pitched 4 times the amount of yeast 1 pk of red star montrachet. now i do know most home brewers do not have to worry about autolysis because they under pitch but i do think here i did hit the propper pitching rate and maybe could have went over?

this is from the BJCP website:


Sulfury/Yeasty

These flavors, not to be confused with DMS, have the aroma and taste of rotten eggs, shrimp or rubber. The compounds responsible for these flavors originate from sulfur-containing amino acids such as cysteine and methionine. Possible sources include yeast autolysis, bacterial spoilage and water contamination. These flavors can be quite putrid and are not desirable in any style. In the same family are sulfitic flavors, which recall the aroma of a struck match. They are usually due to the overuse of antioxidants, and while rare in beer, are quite common in wine and cider.


now the trub from beer is a different substance made of cuagulated proteins and at high fermentations temps can leach off flavors into your beer, but since fruit mead does not have this i was not worried about that. maybe i should have thought about that added yeast.

what do you think Oskaar?
do you think bubbling co2 through the mead will get/help get rid of the aroma, it is currently undrinkable, i was thinking about just giving it to my friend who has a still (for distilling water only) because i can not drink something that is this nasty smelling. which i do not like the sound of i hate dumping, and luckly for 14 years of homebrewing i have only had to do that a few times (worst was the dopplebock which the mash got burned, undrinkable tasted like nasty burnt toast).

now i can readd the lost aroma i can get some honey aroma and strawberry aroma, which i hate using, but if it can rescue this batch i would try it.

i was also thinking that maybe adding a pound or two more of honey and get refermenting and the would scrub the sulfur out witht he co2 action, but i dont want to waste good honey on a lost cause, and i am only talking about a gallon of 1 month old mead, it cost under $15.

wayneb
05-24-2007, 11:54 AM
OK - Oskaar works some crazy hours and he may not be able to weigh back in until tonight, so let me add my 2c. First, everything he advised is good info. But it sounds like you did most of what he suggested, as part of your standard good practice. Yet you still have beaucoups H2S. Why? Well, it turns out that if yeast are not supplied with enough available nitrogen early in their life cycle, then toward the end the way they metabolize sugar follows a slightly different biochemical path, and it results in the creation of a lot more free H2S. Some strains are far more sensitive to this lack of nitrogen than others. H2S what you've got, and I suspect that it results from these two things: 1) Red Star Montrachet, from my experience, is one of those strains that has higher overall nitrogen needs than other strains do. 2) You pitched a heckova lot of yeast for a one-gallon must. 5g of Red Star is usually enough for a 5 gal batch. And, you properly rehydrated it, and you ended up with the maximum amount of viable cells that you could pitch from that pack!

So, in a recipe that is clearly nutrient scaled for 1 gallon, you introduced 5x the number of cells. They gobbled up the available nitrogen in their new environment almost all at once and then they were nitrogen starved for the rest of the time they were in there. Their metabolic cycles now irretrievably altered, they have signaled their distress by skunking you.

Now what? Well, there are a couple of things you can do right away to mitigate some of that smell. First, get as much of it out of solution as possible by de-gassing the must. Stir well, and stir often, and watch all that H2S come to the surface. If that isn't good enough, then you can try adding a clean, bright (as in uncorroded) copper rod to the carboy. Copper house wiring actually works well for this; take a piece of 12 ga copper wire that is about as long as your carboy is tall, strip off the insulation, and then polish the surface of the wire bright with steel wool. Rinse, sanitize, and put it in the carboy. Now (horrors!!) introduce a little free O2 by aerating the must. Yeah - I know - if you do this cavalierly, you'll wreck the mead by oxidizing it, but you're going to be careful and just aerate a little bit. If not, you're going to end up with something undrinkable anyway, so just trust me on this. The combination of free Cu ions and oxygen in the mead will react with the H2S and some of the nastier secondary compounds that are beginning to form, and cause the resulting oxidized sulfur compounds to precipitate out of solution. Leave the copper rod in there for a week after aeration, then check for H2S again. If you're lucky, most if not all of it will be gone.

If you're not lucky, secondary reactions between the H2S and alcohol in the mead will have already taken place and you will have created some raunchy smelling constituents that are not easily removed. If that's true, and you're only dealing with a 1 gallon batch here, I'd recommend that you use it to nourish the nearest septic tank and start over. More sophisticated treatments, involving copper sulfate and ascorbic acid, are possible to remove those secondary compounds, but they must be done with extreme precision, the process is not for the faint-of-heart, and if done incorrectly the result is extremely toxic!

plaztikjezuz
05-24-2007, 05:36 PM
I had to do a google search on the H2S, the chemical compound of hydrogen sulfide .

what method of aeration would yoiu recomend, i have pure o2 injestion stone or just a sloppy transfer to a different jug. i usually transfer blanketed under co2 to prevent oxidation and anything from gettign in my beverages by positive displacement.

i have always use wyeast's yeast nutrient in the past and when i made this batch i was unable to get any and i had run out. so i used fermax, the who i trust at the LHBS said it was better then wyeast's nutrient as it had a wider range of vit's & min's for the yeast. so what would i use to add more nitrogen to the must? i have never added this in the past so it is kinda new.

also i am making a mango mead and do not want this to happen again. should i cut back on the yeast. i was planning on using brewers yeast for this one, i have a good batch of washed wyeast 1214 belgian ale (chimay strain) and really wanted the fruity esters it tosses off.

i have read ken schramms book and follow his procedures as much as possible which in volves feeding the must nutrient when oxygenating. now i only gave the must nutrient 2 times should i give it more?

wayneb
05-24-2007, 06:11 PM
Well, when I've done the copper rod thing all I did was to stir enough to splash it a bit as I transferred it into the carboy that had the copper in it. You really don't want too much O2 at this stage, since all you're doing is providing enough dissolved oxygen to support the clearing of that H2S. The other thing that I should have mentioned is that you should swirl and monitor the aroma from your carboy daily when employing the copper rod treatment. Excessive copper in any solution is toxic, which is why you first try the solid copper treatment before employing more drastic measures such as adding copper sulfate. The rod releases very small amounts of Cu ions over time, but the actual amount of ions released is a function of the pH of the must. Keep the copper in there just long enough to clear the H2S stench - no longer. One week is the longest that you should ever leave it in there. The good news is that in the presence of H2S or methyl mercaptan (the nasty that forms when H2S reacts with alcohol), those copper ions will react and form compounds that precipitate out of the wine naturally, so the residual amount of copper in your wine will decrease as more H2S and mercaptan is reacted.

One other thing that I forgot to mention is that you can also, after the aeration and introduction of a copper rod, introduce sulfites into the must. Although it sounds kind of counter-intuitive, putting some K-META, the source of SO2 version of sulfur, into your wine actually provides a way to react the hydrogen sulfide into elemental sulfur and water. While the elemental sulfur isn't something that you want in the finished product, it too can be removed since it will eventually precipitate out. So another racking after the copper rod and the sulfite treatments are done will remove all the nasties that are easily removed once and for all.

wayneb
05-24-2007, 06:14 PM
BTW - Here's a good web article on the H2S problem and mitigation techniques, for those who want to delve into it a bit deeper: http://www.vawa.net/winemaking-articles/hydrogensulfide.html

Oskaar
05-24-2007, 09:40 PM
...snip

now i see this in your post your directed me to:


“you gotta rack this off the lees and trub right away because letting your mead sit on the lees is baaaad!” That’s a load of hooey, as this recipe and others I have posted will prove to you.


my melomel did sit in the lee and trub for 3-4 weeks and i was thinking this could have something to do with the sulfur? but i have never heard of sulfur be produced by trub in beer but that is protien and not fruit fiber. so who know?
i will tell you from my experiences making beer leaving you beer on the yeast cake for months can lead to autolysis which is a nasty flavor and those flavor can be sulfur. now the one thing that i did do that was different was i pitched 4 times the amount of yeast 1 pk of red star montrachet. now i do know most home brewers do not have to worry about autolysis because they under pitch but i do think here i did hit the propper pitching rate and maybe could have went over?

this is from the BJCP website:


OK, let's not forget that I was speaking VERY VERY SPECIFICALLY about the recipe in which that quote is from, not for ALL melomels, meads, etc. That recipe is designed to gain more and more character from the yeast and the fruit in the primary as it sit. This is NOT a general statement about lees, trub, extended gross-lees exposure, it is directed specifically at my recipe. I just want to make that very very clear.

Also let's not forget that one of the reasons racking is performed very close to the end of fermentation is specifically because of the production of reductive/sulfur characters. The lees at the bottom of the fermentation vessel are known to encourage the growth of spoilage and odor causing bacteria. This is why exposure to the gross lees is counter-intuitive, and the reason that I stated emphatically in the recipe that my process is for that specific recipe and not as a general rule of thumb.

From WayneB

OK - Oskaar works some crazy hours and he may not be able to weigh back in until tonight, so let me add my 2c. First, everything he advised is good info. But it sounds like you did most of what he suggested, as part of your standard good practice. Yet you still have beaucoups H2S. Why? Well, it turns out that if yeast are not supplied with enough available nitrogen early in their life cycle, then toward the end the way they metabolize sugar follows a slightly different biochemical path, and it results in the creation of a lot more free H2S. Some strains are far more sensitive to this lack of nitrogen than others. H2S what you've got, and I suspect that it results from these two things: 1) Red Star Montrachet, from my experience, is one of those strains that has higher overall nitrogen needs than other strains do. 2) You pitched a heckova lot of yeast for a one-gallon must. 5g of Red Star is usually enough for a 5 gal batch. And, you properly rehydrated it, and you ended up with the maximum amount of viable cells that you could pitch from that pack!

These are good observations about Montrachet yeast. If you check the Yeast Test post that I pinned in the BrewLog section of the forums you'll see that the Montrachet yeast produced some nasty off flavors that never did work out. I've added Montrachet to my list of yeast that I don't use any longer because I don't like the character, flavor or anything else about the mead I have produced with it. This is not based on one or two batches, but a number of batches over the years. I just plain don't like the stuff.

On the flipside, I've made plenty of one gallon batches and have used 5 gram packages of yeast without any problems, so I think we're talking about a combination of things here that lead to your problem.

OK, I'm going back to acid/pH and nutrient on this as Wayne did.

The internal pH of a yeast cell is near neutrality (pH 6.5- 7.0), while the pH of the medium is 3.0 to 4.0. This creates a large gradient of protons, and entry of hydrogen ions into the cell is energetically favorable. Therefore, movement of amino acids is coupled with that of protons. Amino acid transporters transfer both an amino acid molecule and a proton into the cell. The proton is then exported out of the cell via a proton pump. The pump extrudes protons in an energy dependent manner since excretion occurs against the proton gradient.(Bisson 2005)

Hydrolysis of ATP provides the energy for operation of the pump. Continued amino acid uptake requires efficient excretion of the protons that are being co-transported with the amino acid; so amino acid uptake is a very energy intensive process.

Since amino acid uptake is coupled to protons it's no mystery that the pH of the medium (must in this case) affects amino acid uptake. If the pH is too low, below 2.7, protons tend to enter the cell due to passive proton flux. The proton pump must then be directed towards removal of these protons. The cell has a limited capacity for the removal of protons, thus at very low pH the cell is not able to sustain amino acid uptake due to the lack of capacity of the proton pump.

So, while this is a clone of a recipe that worked out well before, it certainly does not rule out an acid/pH issue preventing the proton pump from functioning properly and carrying out the proton excretion against the proton gradient, which in turn will affect the yeasts ability to effectively metabolyze the nutrients available in the must no matter how much you added.

There are several other factors that impact fermentation and H2S production that are associated with pH as well.

So what I think you have here is a situation where your pH may have been acidic to the point of where the cell metabolism was compromised from the beginning. Once that happens future generations of your yeast are not ideally formed and off odors and flavors will be produced due to yeast stress.

Hope that helps,

Oskaar

plaztikjezuz
05-31-2007, 01:45 AM
the pH of my water is 9.34 i do not know if the honey would lower (i'm guessing it will). i did not take a pH reading of the must so i do not know what it was before pitching.

wayneb
05-31-2007, 11:47 AM
YOW! That's a very high pH for drinking water. What's your total hardness and total alkalinity? You're right up almost at the limit of what the World Health Organization recommends as acceptable for potable water without external treatment. One thing to consider -- whenever high alkalinity water is found, often there are high concentrations of sulfur compounds.