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Bua Bheach
08-04-2013, 12:37 PM
Dear fellow... brewers is it?

At the 13th of last month, 13-07-2013, I finally got around to make my first 4 batches of meade.

4 Bottles, of about 2.5 liters each.

The first batch is 2x500 g cheap stuff bought at the Aldi (the europeans will know).
The second batch is 2x450 g Acacia honey.
The third is 2x450 Thyme honey.
And the forth 2x500 gram Sali honey.
The last 3 bought at a local bio-shop

The yeast is Bioferm Killer (Saccharomyces bayanus), 7 g. devided over the four batches with a teaspoon of nutrients and a teaspoon of lemonjuice.

This all led to 4 nice bubbling batches, not the wild stuff the internet warned me about.

The internet also led me to believe that all I had to do now was wait for about 4 to 6 months.
So I was a bit surpised to notice that the 2nd batch had stopped bubbling after a little over 2 weeks, and was even trying to suck air in through the airlock.
Asked advice to some beerbrewers, and they suggested that fermentation could very wel be finished, and it's time to bottle.

So after 2 days of gathering and cleaning bottles and further equipment, I was ready to bottle my first batch.

Only to notice that the batch was once again fermenting.

Is this a normal part of the process?

One brewer made the remark that the yeast might have died through heat, but all 4 batches are in the same room, same square yard even, so don't believe that is the issue.

I hope someone here can shed a light on it.

joemirando
08-04-2013, 01:11 PM
Dear fellow... brewers is it?

At the 13th of last month, 13-07-2013, I finally got around to make my first 4 batches of meade.

4 Bottles, of about 2.5 liters each.

The first batch is 2x500 g cheap stuff bought at the Aldi (the europeans will know).
The second batch is 2x450 g Acacia honey.
The third is 2x450 Thyme honey.
And the forth 2x500 gram Sali honey.
The last 3 bought at a local bio-shop

The yeast is Bioferm Killer (Saccharomyces bayanus), 7 g. devided over the four batches with a teaspoon of nutrients and a teaspoon of lemonjuice.

This all led to 4 nice bubbling batches, not the wild stuff the internet warned me about.

The internet also led me to believe that all I had to do now was wait for about 4 to 6 months.
So I was a bit surpised to notice that the 2nd batch had stopped bubbling after a little over 2 weeks, and was even trying to suck air in through the airlock.
Asked advice to some beerbrewers, and they suggested that fermentation could very wel be finished, and it's time to bottle.

So after 2 days of gathering and cleaning bottles and further equipment, I was ready to bottle my first batch.

Only to notice that the batch was once again fermenting.

Is this a normal part of the process?

One brewer made the remark that the yeast might have died through heat, but all 4 batches are in the same room, same square yard even, so don't believe that is the issue.

I hope someone here can shed a light on it.
Bua Bheach,

First of all, welcome! I'm fairly new to mead also, so I know the feeling of uncertainty you have.

My first recommendation is to buy a hydrometer. It really is necessary equipment. Without SG readings, you don't know if the yeast has converted all or most of the sugars into alcohol, or if something has gone wrong and fermentation is just stalled.

The 4 to 6 month wait is to completion, not the end of fermentation. I have a batch sitting in a gallon (4 liter) jug right now that has fermented dry in 9 days. Full fermentation is dependent upon many factors: your beginning concentration of sugars, the ambient temperature, aeration, available nutrients, pH, etc., so it is very hard to tell for sure what your situation is without specific gravity readings.

I am guessing that you are seeing renewed bubbling in the airlock, and this is what you are assuming is fermentation. It could be, but it could also be outgassing; that is dissolved CO2 coming out of solution.

The mead calculator on this site (http://www.gotmead.com/index.php?option=com_content&task=view&id=745&Itemid=16) calculates that your original SG would be about 1.120 (H2O = 1.000), with a maximum possible ABV (alcohol by volume) of 15.54%.

It is not impossible that your mead is done fermenting, but it is hard to know without hydrometer readings.

When all else fails, patience is often the answer. Patience has been the most difficult ingredient for me to find.

I am sure that more knowledgeable people than I will jump in and fill in the blank spaces I have left or correct me. THIS way, we BOTH get to learn. ;)


Good luck,

Joe

fatbloke
08-04-2013, 03:00 PM
Never believe the beer brewers....... ;)

They make quick fermenting, easy to brew stuff that takes 10 minutes.... and they have hygiene fetishes :D

Dunno about the slowing/restarting ferment thing unless you've used plastic fermenters and had some weather changes. Dunno if that yeast is a bioferm packaged version of the Montpellier strain (lalvin packs being k1v1116)..... if its like I'm thinking then it'll likely ferment dry....

1 teaspoon of nutrient spread across the 4 batches ? Likely not enough. More like a half to 1 tsp for a smooth ferment.

I have no idea of the point of the lemon juice ? Adding acids up front isn't advised any more. You're making traditionals basically, so you might need a bit of acid later (I dont like citric acid as it flavours too lemony. I mix 2 parts malic and 1 part tartaric).

Chevette Girl
08-04-2013, 04:25 PM
Joe's bang on with his suggestion to get a hydrometer, anything else we come up with will just be speculation without knowing what your specific gravities are and whether they're still changing.

I'd bet a temperature or pressure change is the explanation... as yeast ferments sugar, it produces carbon dioxide, a certain amount of which dissolves into the must and the rest excapes as bubbles, which make their way out the airlock. This amount that the liquid can hold changes with the temperature, the colder the must, the more CO2 it can hold before it releases it in the form of bubbles (think of how much faster a warm beer goes flat than a cold one).

A drop in temperature also causes the volume to decrease, which would cause a drop in the pressure inside the vessel, which is why it was sucking back the liquid level on your hydrometer.

My guess would be that the one that stopped for a bit had fermented a bit faster than the rest for whatever reason, and you had a temperature drop over a day or two. While the others were still producing enough carbon dioxide to offset the volume decrease and the decrease in released carbon dioxide, this one batch wasn't producing enough CO2 at the time so it looked like it stopped fermenting.

Oh, and your beer brewer friends? Listen to them when you're making beer, but if you're making wines or meads, check out a wine or mead forum... without going at least a couple weeks to make sure your SG isn't changing anymore, bottling THAT quickly after the end of visible bubbling without having added stabilizing chemicals is just asking for popped corks or even bottle bombs (not at all funny). Wines and meads are stronger than beers and usually take longer. You'll want to give these a couple weeks to clear at the very least, and if you don't know if there's any residual sugar, you'll want to add sulphites and potassium sorbate to make sure the yeast are knocked out and unable to reproduce.

And as Fatbloke said, when making meads you really don't want to add acid up front, honey has its own acidity and we often end up with problems from too much acidity making the fermentation stop early or slow down significantly.

Bua Bheach
08-05-2013, 01:34 PM
Well, thanks so far.

A hydrometer, I'll look into that, should be able to dig one up at the brewstore where I got the rest of the stuff.

A bit more detail, it was one teaspoon per batch, and the acid I got from a recipe, but I'll try without later, see what gives.

As all 4 batches are in real close proximity, temp and pressure drop look to me a bit out of the question. Not to mention the heatwave we're having here in Belgium for the last 2 weeks.

And so the secret's out, living in Belgium, the world beer capital and with close to 10 years of working in a couple of breweries, you might guess my view is a bit colored by beer bottles.

But then again, I'm usual the odd one out.