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Isilme
01-17-2011, 02:50 PM
Yesterday I made two batches: one beer and one mead. The beer is bubbling away like crazy, the mead, well, not...

I made an almost 20l batch and sanitized everything thoroughly, added all necessary things (I think), checked the temperatures, etc. Here is the link to my brewlog: Brewlog (http://www.gotmead.com/forum/showthread.php?t=17277)

So after 24h nothing has happened. I'm sitting next to it now and it made for or five small bubbles and then stopped again. The water also flowed back in the airlock. The mead is almost 20l and is in a 30l fermenting bucket. The yeast was an already open package I stored closed in the fridge for 18 days.

So; what are possible reasons? My yeast died in the fridge? Is is possible that I aerated so much that the yeast is first multiplying and using aerobic metabolism in stead of producing ethanol? Maybe I filled my airlock too much? Do I need to measure pH or something? I didn't add citric acid, like I normally do, because I thought there would be enough acid in the oranges and cranberry. Maybe there's too much sugar? Or maybe I'm just too impatience?

I'm a bit worried because this is the biggest batch I ever made and also the most expensive one. If this one fails, I'd be sad :(

Medsen Fey
01-17-2011, 03:05 PM
Airlocks can leak and are not reliable to assess fermentation. Check your gravity and see if it is dropping.

If not aerate it again and wait to see if it goes faster. The yeast can often take longer than 24 hours to get going especially if the temperature is cool.

If it isn't going:
What temperature are you maintaining? (lower means a slower start)
Can you check the pH? (cranberry juice can cause low pH)

YogiBearMead726
01-17-2011, 03:05 PM
It could be that your SG was too high, and caused some osmotic stress on your yeast. Though, looking at your brewlog, doesn't seem that way.

Lag phases can last for 48 hours (or even longer! This is especially true when you start with a high gravity) so my first thought is be patient. It could also be that it's too cold. Try moving the fermentation vessel to somewhere a bit warmer.

I don't think pH is the issue, but it can't hurt to check. Your cranberry/oranges might have caused a pH dip, but as long as the must is around 3.2, you're golden.

You also can't "over aerate". At some point, you can't saturate any more O2 into the solution. So, good job on aeration! ;)

If nothing else, you can always pitch some new yeast by making a starter. Grab some of your must and put it into a vessel you can airlock. I like diluting it a bit if SG is really high, add some fresh yeast, and let this ferment for awhile. Then, pitch into your must. But again, just be patient. I bet those yeasties are still adjusting to their new home. :)

Edit: Medsen proves to have faster fingers once more. :p

Isilme
01-17-2011, 03:27 PM
Thank for your fast replies the both of you! :)

I know I am impatient :rolleyes: The temperature is 21C. I think that's enough? I can't measure the pH sadly (I'll knick the pH meter of our lab tomorrow!).

I always thought it was not allowed to open the vessel when fermentation started ??? I thought fermentation was an anaerobic process and when you would open the vessel and aerate it would disturb the fermentation process.

I didn't take an SG reading yet *blush* Is it still useful if I do it know?

On the other hand I think I do see some kind of "yuck" clinging to the side of the fermentation bucket (above the fluid level).

I thought about repitching, but, trouble oh trouble! I used the last grams of this yeast strain and I only have other yeasties available. I can't repitch with another strain, now can I?

Thanks again! Having this forum at hand and you guys for troubleshooting-help makes me feel more comfortable!

mccann51
01-17-2011, 03:43 PM
I always thought it was not allowed to open the vessel when fermentation started ??? I thought fermentation was an anaerobic process and when you would open the vessel and aerate it would disturb the fermentation process.

I didn't take an SG reading yet *blush* Is it still useful if I do it know?


Aerating/oxygenating the must is very helpful in the early stages of "fermentation" to allow the yeast to reproduce and get a good population size so they can more effectively convert your sugar to alcohol. The standard cutoff for when you want to aerate until is when 1/3 of the sugar that the yeast can covert is converted. So, if you have a OG of 1.120, and you're using a yeast that will ferment the must dry, then you'd want to aerate until 1.080.

It is never too late to take an SG measurement. If you take one today and then take one tomorrow, you'll know if the yeast are converting sugar; if you never take one, you'll be relying on your airlock.

Isilme
01-17-2011, 03:43 PM
I think the Mead Gods listened to my prayers, cause five mins after my last post, the mead is bubbling like CRAZY! The water almost splashed out of the airlock! I'm happppyyyyyy!!! :hello2:

YogiBearMead726
01-17-2011, 03:49 PM
I know I am impatient :rolleyes: The temperature is 21C. I think that's enough? I can't measure the pH sadly (I'll knick the pH meter of our lab tomorrow!).

That's a bit on the cool side. I'm not sure on that yeasts specifics, but I'd try to bump it up to 22-23C. Might just be that small difference that makes the yeasties wake up.


I always thought it was not allowed to open the vessel when fermentation started ??? I thought fermentation was an anaerobic process and when you would open the vessel and aerate it would disturb the fermentation process.

This is true...sort of. You don't want to keep feeding oxygen into the vessel once fermentation has gotten past a certain point. This is another reason why SG readings are key, because you know what your yeast are doing and at what point to give them what nutrients and when to let them be (oxygen included). A lot of traditional wine making/beer making was done with open fermentation vessels. While the purpose was slightly different then (they wanted to inoculate with some wild yeast in the air and aerate the must/wort), at home, it's perfectly ok to ferment with a sanitized piece of cheesecloth covering the fermentation vessel for at least the first sugar break (1/3 of the sugar gone...again, you need to take an SG reading to know when this is) and at most the second break (2/3 gone). After that point, minimizing exposure to air is important.


I didn't take an SG reading yet *blush* Is it still useful if I do it know?

Yes! :p It will at least give you an idea of when the yeast wake up, since you can take a measurement later (in say 24 hours) to see if any drop in SG has occurred.


On the other hand I think I do see some kind of "yuck" clinging to the side of the fermentation bucket (above the fluid level).

Don't worry too much about that for now. As long as you sanitized things properly, you can always give it a really good cleaning after you rack this into secondary. If really bad odors/flavors develop, then you'd be in trouble.


I thought about repitching, but, trouble oh trouble! I used the last grams of this yeast strain and I only have other yeasties available. I can't repitch with another strain, now can I?

Sure you can! There are a lot of factors which dictate whether or not two strains can live together, but if you pitch something like K1V-1116, the other strain (if it's not already dead/stuck) will be history. However, this will affect the final ABV/sweetness as the strains used to fix "stuck" batches tend to have tolerances around 16-18% ABV...so...I'd only go this route if absolutely necessary, since your original post indicated you wanted a semi-sweet 14% final product.


Thanks again! Having this forum at hand and you guys for troubleshooting-help makes me feel more comfortable!

That's what I love about this site. Everyone is here to help everyone else make a better mead. :)

akueck
01-17-2011, 03:49 PM
Fermentation is not by definition anaerobic. It can occur under those conditions, but it will still happen in the presence of oxygen. The oxygen in the beginning of the process is necessary for building cell walls, which the yeast need lots of as they divide rapidly (doubling around once a day!). Adding oxygen later in the process won't stop fermentation, but if you add more than the yeast use it can start reacting with other compounds to create off-flavors. Thus the 1/3 break rule, which should give you enough oxygen for the yeast population to stabilize but not too much so that you get cardboard-mead.

YogiBearMead726
01-17-2011, 03:51 PM
I think the Mead Gods listened to my prayers, cause five mins after my last post, the mead is bubbling like CRAZY! The water almost splashed out of the airlock! I'm happppyyyyyy!!! :hello2:

Lol...and I spent all that time typing. :rolleyes:;)

Sometimes, patience is all you need. That said, you should still take an SG reading now to give you a base point/estimate of original gravity.

Isilme
01-17-2011, 04:23 PM
Lol...and I spent all that time typing. :rolleyes:;)

I'm sorry :( I need to be more patient - next time I won't panic so soon, I swear!

But still; wow I just learned A LOT with all your posts! So your typing effort was not wasted at all.

Thanks tremendously!