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j.postema
02-09-2009, 09:52 AM
Hi all,

I used to aerate only the first 3 days after pitching the yeast. I read that most people aerate till 1/3 sugarbrek, so I decided to do more aeration until 1/3 sugarbreak.

The first 5 days I stirred twice a day. After that I put the mead in a air-locked carboy. The mead just started to ferment so I think it will take a few day before 1/3 sugarbreak is reached. During that time I want to stir / aerate daily.

Yesterday I stirred the mead and there was a lot of foam-forming when I stirred the mead. A few minutes after stirring, the foam disappeared.

My question: should I still aerate till 1/3 sugarbreak alhough a lot of foam is creaded during daily stirring? Is it just CO2 that is released and no problem?

Is it of any use at all to do aeration after fermentation is starten but 1/3 sugarbreak is not reached?

liff
02-09-2009, 10:05 AM
My question: should I still aerate till 1/3 sugarbreak alhough a lot of foam is creaded during daily stirring? Is it just CO2 that is released and no problem?

Is it of any use at all to do aeration after fermentation is starten but 1/3 sugarbreak is not reached?

1) Yes.

2) Correct.

3) Absolutely.

Sounds to me like you are doing it "right" and should have faster, more complete ferments as a result.

j.postema
02-09-2009, 10:13 AM
Hi liff,

thanks for your reply! I always tend to hesitate about things and I'm still rather new to this nice hobby... But it's clear now so I just continue the daily stirring till 1/3 sugarbreak. I'm curious if it will make a difference!

Medsen Fey
02-09-2009, 10:22 AM
I'm not sure why it is taking 5 days for your mead to get started. If you can post the full details of the recipe and process perhaps someone here can pinpoint the cause for the slow start.

I do typically aerate until the 1/3 fermentation point, usually once a day unless there is a cap involved and I am managing the cap more frequently. Is that more than necessary? Probably. In some studies done with wine fermentations, the maximal yeast growth and fermentation of sugar could be accomplish with aeration occurring only on the second day of fermentation. Granted, our mead fermentations often start with gravities quite a bit higher than most wines, and may need aeration/oxygen more than a typical wine. This would be a useful, and relatively simple study to conduct.

For me the key is that I usually reach the 1/3 fermentation point quickly, often within 48 hours, so I'm not looking at prolonged days of aeration.

It is normal to get foaming with aeration and agitation and one can experience a MEA (Mead Eruption Accident) when aerating if it is not done carefully. Antifoam drops (http://www.eckraus.com/INSTANT_ANTI/Page_1/FM210.html) can significantly reduce this problem, and using a primary fermenter such as a bucket (or other vessel with plenty of headspace) is wise.

I hope that helps.

Medsen

j.postema
02-09-2009, 11:31 AM
Hi Medsen,

thanks for your reply. I will check how long it will take before 1/3 sugarbreak is reached.

j.postema
02-14-2009, 06:43 PM
Hi,

recipe:

3 x 1 liter grape-juice from supermarket;
about 1 to 1.5 kg wild-flower honey;
added tap-water to 1 gallon total volume;
added yeast nutrient;
added a few raisins;

january 31:
pitching yeast in open fermenter

february 4:
starting gravity: 1116, no fermentation activity, stirring 2x a day

february 7:
put mead in air-locked carboy, after a few hours it slowly starts bubbling

february 8:
stirred the mead, s.g.: +/- 1112

feb. 9:
stirred the mead, s.g.: +/- 1100

feb 11:
stirred the mead, s.g.: +/- 996

Since 3 days bubble rate has increased to 1 bubble every 1 second and there is a lot! of CO2 bubbles raising in the mead, I can even hear it foaming inside the locked carboy! Compared to previous batches much more fermentation activity!

It looks like after a (very) slow start it finally started to ferment well. I have to admit that during the first days i did not regulary / frequently stir the mead.

Medsen Fey
02-15-2009, 01:00 PM
One way to get a much faster start is to rehydrate your yeast before pitching them, preferably with GoFerm or a similar product to help the yeast. Doing this shortens the lag phase of fermentation down to hours (if not minutes) as the yeast really hit the ground running.

There's a good thread on rehydration by PBakulic (http://www.gotmead.com/forum/showthread.php?p=92260#post92260).

Temperature can also be a factor in the speed with which the yeast get moving.

Medsen