One of the most unfortunate experiences when making mead is opening your fermenter and immediately being put back by the smell. Maybe it smells like rotten eggs. Maybe it smells like hot alcohol. Maybe it smells like something you can't even identify but you know it shouldn't smell like that. Don't panic. I've been there more times than I'd like to admit, and in most cases, your mead is going to be just fine.
Off smells during and after fermentation are one of the most common concerns I hear from beginners, and honestly, they freak people out way more than they should. So let's talk about what causes them, which ones are actually a problem, and what you can do about it.
Most of the Time, It Goes Away
I want to lead with this because it's the most common answer and the one that saves the most batches from being dumped down the drain. Time fixes most off smells. Seriously. Many of the funky aromas you pick up during active fermentation (or after) are byproducts of yeast simply doing their thing. As your mead ages, these compounds either break down, off gas, or get masked by other flavors developing in the background.
I've had batches that smelled terrible at two weeks and turned into some of my best meads after a few months of aging. If your mead smells a little weird but doesn't look infected (no mold, no weird film on top), give it time before you make any drastic decisions.
So Why Does My Mead Smell Bad?
There are a few common culprits, and knowing what you're smelling can help you figure out where things went sideways.
Sulfur (Rotten Eggs)
This is probably the most common off smell in mead, and it's almost always caused by stressed yeast. When yeast don't have enough nutrients to work with, they produce hydrogen sulfide, which smells like rotten eggs. Honey and water alone do not provide adequate nutrients for yeast to thrive, which is why proper nutrient additions are so important. I go over this in detail in my article on mead nutrients for beginners, but the short version is that step feeding Fermaid O during the first few days of fermentation gives your yeast the nitrogen they need to stay healthy and produce fewer off flavors. This is why I include nutrients and feeding instructions in all my mead making starter kits.
Lack of oxygen early in fermentation can also contribute. Yeast actually benefit from oxygen during the first couple of days, which is why I recommend vigorously stirring your must when you add your nutrient doses. After nutrient dosing is complete, leave it alone.
The good news is that sulfur almost always goes away on its own. Racking your mead (transferring it to a new vessel) exposes it to just enough air movement to help the hydrogen sulfide dissipate. If the smell persists after a couple of rackings, there's an old winemaker trick that works surprisingly well: add a copper scrubber to your fermenter. Copper reacts with hydrogen sulfide and neutralizes the smell. I've seen it work almost instantly on batches that had been smelling rough for weeks. Just make sure you're using actual copper, not a copper plated steel scrubber, because those will corrode and rust.
Can Fruit Cause Off Flavors in Mead?
Absolutely. And this one catches a lot of people off guard because they expect their fruit mead to taste exactly like the fresh fruit they put in. Fermentation changes things.
Bandaid or Rubber Notes (Strawberries)
Strawberry meads are notorious for producing a bandaid, medicinal, or even rubbery character. This is a phenolic off flavor, and typically phenolic aromatics are considered a fault and should not be present in a well made mead. Phenolics can come from wild yeast, bacteria, or even sanitizer residue, but with strawberries specifically, the fruit itself seems to contribute compounds that ferment into something that reads as medicinal or plastic-like.
I've had a strawberry mead that smelled exactly like rubber tires during the fermentation process. I'd notice the smell coming from the airlock without even having to remove the lid. Luckily, by the time fermentation was complete it had completely dissipated and there was no effect on the taste. But for preventative measure, you can mitigate off scents with proper sanitation, and lightly freezing and mashing fruit (not blending, more on that later).
Minty or Menthol Notes (Cranberries)
This one is oddly specific but I've seen it come up enough to mention it. Cranberry meads can sometimes produce a subtle minty or menthol quality that's unexpected and a little off putting if you're not ready for it. It's not a sign of infection or anything dangerous, it's just a quirk of how cranberry compounds interact with fermentation. Again, aging tends to soften it, and blending with other flavors can help. My Spiced Cranberry Cyser recipe uses additional spices and hops in secondary that do a great job of balancing out any odd cranberry notes.
Crushed Seeds and Bitter Off Flavors
This one is easy to prevent but annoying to fix after the fact. When you mash or blend fruit for a melomel, be careful not to crush the seeds. Berry seeds in particular (blackberries, raspberries, strawberries) contain tannins and other compounds that can add harsh, bitter, or astringent flavors to your mead. I never recommend using a blender for this reason. Always mash by hand or freeze and thaw your fruit, which breaks down the cell walls without touching the seeds. A brew bag is your friend here because it makes it easy to keep fruit (and seeds) contained and remove everything at once.
How Do I Know If My Mead Is Actually Ruined?
The BJCP mead exam study guide lists a number of common faults that judges look for, and understanding a few of them can help you figure out if you have a real problem or just a young mead that needs more time.
Clean and fresh aromatics are always preferred over dirty, yeasty, or sulfury notes. Phenolic or diacetyl aromatics should not be present. Harsh or chemical aromatics are a defect. Oxidation resulting in a papery character is always undesirable. And hot, solventy, or irritating alcohol overtones are a fault.
If your mead smells like vinegar, that's acetic acid from a bacterial infection, usually caused by a sanitation issue or too much oxygen exposure after fermentation. If it smells like nail polish remover or solvent, you've likely got fusel alcohols from fermenting too warm or without adequate nutrients. Those are harder to fix and sometimes can't be fixed at all.
But rotten eggs? Mild rubber from strawberries? A little minty note from cranberries? A funky yeasty smell during active fermentation? Those are all things that either go away on their own or can be managed. Don't dump the batch.
One thing to note: if your mead smells different from anything described above or it is foul like something is obviously rotting, I would err on the safe side and start over. It sucks, but it's not worth the risk of something actually being dangerous. Check out my blog about mold in mead for more on that...
Quick Recap
Feed your yeast properly with nutrients. Stir vigorously during the first couple of days to provide oxygen. Don't crush seeds when prepping fruit. Know that certain fruits like strawberries and cranberries carry their own quirks. Use copper if sulfur won't quit. Ferment at temperatures your yeast was intended for. And above all, be patient. Most off aromas are temporary.
If you want a full walkthrough of the entire process from start to finish, check out my guide on how to make mead for beginners.
Cheers, and don't let a funky smell scare you off!
Sources:
- BJCP 2015 Mead Style Guidelines: bjcp.org
- BJCP Mead Exam Study Guide, Chapter 10: Common Faults: bjcp.org
- Got Mead, Mead Descriptor Definitions and Faults: gotmead.com
- Golden Hive Mead Recipe Guide