Hazelnut problems

[Curvasud93]

Hey everyone!
I made a 10liter hazelnut honey mead on last Friday.
I had a very vigorous fermentation till Monday after that it slowed down and today (Thursday) it stopped.
When i opened it smelled like rotten eggs, the taste was bitter and sourish/acidic cant tell for sure. Dont know if its the taste but i cant feel any alcohol in it ???

The OG:1,078
FG:1.035


Recipe:

3kg Hazelnut honey
Half a packet of wine yeast
filtered water
and 10 grams of yeast nutrition

Is this normal? If not , can it be saved?

 

[Devin Petry-Johnson]

I'm still new so someone with more experience can probably give you more info. But from what I've learned that smell is sulfur acid and it can ruin the mead. You should immediately stir vigorously until you completely degass the must. If you don't get the smell out, it will become part of the taste and it will never age out. Start there.

Also, it looks like you might not have used enough yeast. After you get the smell out, you might consider pitching in another batch of yeast (maybe more than before) to get it going again.

 

[Toxxyc]

At what temperature did you ferment the mead at? Did you rehydrate the yeast or pitch dry? What yeast was it? Did you sterilize everything properly? Did you ferment in a proper fermenter with an airlock? Did you aerate the must before pitching the yeast?

The above questions will help determine where the problems might be. From initial indications it might look like your must wasn't aerated properly, and your yeast was VERY stressed. Sour/acids might indicate oxygen during the anaerobic phase of the fermentation. All is not necessarily lost, so don't panic

PS: Someone's been listening to Squatchy's podcasts

 

[Curvasud93]

The fermentation was on room temperature, but i noticed that the carboy heated up during the fermentation, so i opened the window to cool it down.
I rehydrated the yeast, and the type of yeast is a random Hungarian type for white wines.
For sterilizing i did everything as before, didnt had any problems till now.
Yes i fermented in a 10liter carboy with an airlock
And yes i aerated the must pretty much.

Although i added some potassium metabisulfites after the tasting... hopefully i didnt make it worst.
And i started aerating it by shaking the carboy.

 

[bernardsmith]

Hi Curvasud - and welcome to the forum. A smell of rotten eggs is caused by the presence of hydrogen sulfide and hydrogen sulfide is caused by yeast under stress. Stress can be caused by many things including insufficient nutrients. But you added nutrients although you don't specify what kind. So that might be one source of the problem.

You say you pitched half a pack of yeast. Was that all you had (so the yeast itself might have been infected with bacteria) or had you opened the pack and simply used half? If so, why? You cannot as a home mead maker over-pitch yeast. You can certainly under-pitch yeast and that might be another reason why you smell the presence of H2S (hydrogen sulfide). A very active (an appropriately active) fermentation will blow off H2S if it is produced whereas a sluggish fermentation won't. And while stress is one cause of the production of H2S some strains of yeast are known for their propensity to produce this gas even under optimal circumstances.
Can your mead be saved? Possibly. What I would do is whip air into it (I know. I know. Oxidation. But oxidation is a longer term RISK and the presence of H2S is a current PROBLEM). Whipping air into the mead might drive out the H2S. You might try racking the mead but allow the liquid to run down the sides of the target carboy. That also allows more surface area of the mead to be exposed and that will encourage the H2S to be expelled. A third possibility is to go to your supermarket and look for copper scrubbing wool (the type of scrubber you use to clean pots and pans). Place this at the end of your racking tube and siphon the mead through the copper. Copper will bond with the sulfur forming tiny amounts of copper sulfate and the hydrogen will bond with the oxygen and form water. In such tiny quantities copper sulfate is not toxic.

 

[Squatchy]

I would make sure your copper scrubby is pure copper. Lots of them are copper coated. I would suggest a copper fitting from Home Depot. Hand it from a fishing monofilament

 

[Curvasud93]

You say you pitched half a pack of yeast. Was that all you had (so the yeast itself might have been infected with bacteria) or had you opened the pack and simply used half? If so, why? You cannot as a home mead maker over-pitch yeast. You can certainly under-pitch yeast and that might be another reason why you smell the .

I used 10g yeast nutrient from Enartis. The yeast packet is 20grams and the packet says that this amount is for 1hl so i thought what can go wrong if theres no overpitching so i split it into half , and as i used this yeast strain before and never experienced this.
But yes the very active fermentation is the cause , the airlock was puffing CO2 every in every second.

 

[bernardsmith]

Active fermentation would push out the H2S. It would not itself be the cause of the problem. The cause is located with the yeast - either the strain of yeast is susceptible to heavy production of H2S (I believe that all yeast produce some hydrogen sulfide) or the yeast were stressed perhaps by a shortage of nitrogen or even too low a fermentation temperature.
Check out the following for a brief summary http://www.lallemandwine.com/wp-content/uploads/2017/05/WE-7-H2S-production-by-wine-yeast.pdf

 

[Curvasud93]

Racked the heck out of it and it became drinkable. The taste of the mead is very plain, should i just add some honey to boost up the flavour?