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archimedesbathtub
10-15-2006, 09:01 PM
OK, I didn't want to say 'stuck fermentation' because I'm not ready to give up yet. Here's what I did:

21 lbs of orange blossom honey and 10g of fermaidK to a volume of 5.5 gallons water to give a gravity of 1.140. Temp of must was 73F.

Yeast was 10g of K1V-1116, rehydrated w/ 12g of Goferm in 170mL of water at 105F. After 10 minutes, 170mL of must was added. 10 minutes later, the yeast slurry was added to the must.

The mead was oxygenated w/ pure oxygen thru a .5 micron stone on days 1 and 2.

Now, a week later, the gravity is 1.110. Activity out of the airlock about a bubble or two a second. The temp of the must is 61F.

Is it the temp? Will warming up the must help, or am I really stuck? Please help!!

WRATHWILDE
10-15-2006, 09:20 PM
Yep, Id say it's the temp that's slowing you down. Even bumping it up to 68 would be a pretty big boost. K1V's range is from about 50 to 95, somewhere close to the middle would probably be best 68 to 72 is where I'd try to keep it if it were my batch.

Wrathwilde

GrantLee63
10-15-2006, 09:21 PM
I don't know .... 60 - 120 bubbles per minute coming out of the airlock does not seem slow to me ! My personal thought is that this fermentation is just fine, and the SG will drop in due time. Unless you meant one or two bubbles per minute ?

- GL63

WRATHWILDE
10-15-2006, 11:07 PM
I must have misread it, your right GL63, one to two a second isn't slow at all and would be chugging along quite nicely.

Wrathwilde

Oskaar
10-15-2006, 11:28 PM
Hi Arch,

You also didn't mix up your Go-Ferm in the proper dosages. Your H2O volume should have been about 100 ml (93 if you want to be exact). Remember you add 1.25 grams per gram of yeast (so your Go-Ferm should have been 12.5 grams) and the water volume is 17 ml of H2O/gallon of must (5.5 gal X 17 ml = 93 ml total, I just round up to 100)

So your concentration of Go-Ferm was a bit weak. K1 will definintely chew through that, just give it some time. I'm sure your temp is OK K1 is pretty tolerant of low temperature as well.

Keep us in the loop,

Oskaar

archimedesbathtub
10-16-2006, 04:55 PM
OK, the mead is up to 68F, and the bubble rate is 34 bubbles per minute.

I miss read the yeast rehydration instructions, I thought it was 17mL of water per gram of yeast... hence my 170mL. But hopefully it didn't screw it up too bad.

So, what consequences will this uber slow fermentation have upon my mead? Will it turn out differently than if the fermentation was done in 5 days?

WRATHWILDE
10-16-2006, 06:45 PM
Arch,
34 per minute is not slow!!! That's a very common speed during initial fermentation. It's doing fine, once it slows to about once every 15 to 20 seconds then I'd suggest racking off your lees to your secondary.

Wrathwilde

archimedesbathtub
11-21-2006, 02:35 PM
OK, I think I can say my fermentation is stuck now. It's been about 4 weeks at a controlled internal temperature of 68F, and the gravity hasn't changed in the last week and a half... I'm stuck at 1.050, which is at least a solid 30 points above where I wanted to be.

So what do I do now? Why did my fermentation crap out at 11.8% when everyone says this yeast goes strong and consistently to 18%? I thought I followed all the advice/directions found here. Where did I go wrong?

Am I now destine to drink 5 gallons of really sweet mead?

-Chuck

Leonora
11-22-2006, 12:45 AM
What's your pH? I've sometimes gotten slow/stuck fermentations to revive by adjusting the pH up a smidge.

How about adding some apple juice/cider? That often seems to encourage yeast.

Have you tried "yeast energizer"?

How about adding some water to thin things out a bit?

I'd try tinkering with it a bit and also getting it a bit warmer, say like above 70 degrees F.

I have tried all of the above to ramp up fermentation in various combinations.

Leonora

Rhianni
11-24-2006, 06:04 PM
Arch.
I am not sure what your expectation is but your initial post on 10-15-06 said your airlock was going 1-2 a second and gravity was 1.140. Thats not anywhere near stuck. Thats pretty healthy actually. Stuck is when there is no activity at all.
On 11-21-06 you posted that its at 1.050. In 1 month I usually expect a 1.090 starting gravity to reach about 1.005 - 1.010. So very roughly speaking your yeast is right on track. Both yours and my normal meads drop 0.09 gravity in about a month. Keep in mind that 21 lbs of honey is a LOT. Its might be going a little slow but if there is still activity then let the poor yeasties do their thing.

If activity slows dramatically like 4 per minute or so then add in yeast energizer and yeast nutrient.

Rhianni
11-24-2006, 06:07 PM
So, what consequences will this uber slow fermentation have upon my mead? Will it turn out differently than if the fermentation was done in 5 days?



personally I would be very scared if a 1.140 starting gravity mead was done in 5 days. Again I think your expectations might be a little high. These things take months not days. But dont be discouraged. I made a 21 lbs honey mead as my first batch. I thought I was doing it wrong and ruined it. Age fixes a lot of mistakes and you will eventually have some very sweet, very potent stuff :)

Oskaar
11-24-2006, 07:23 PM
Hey Arch,

I wouldn't be too worried about a very fast fermentation. I've had several cyser batches go from 1.15 down to 1.020-1.030 in 5-7 days, so a five day ferment is not necessarily a bad thing. I've had Zinfandel pyments go off in 4 days to complete dryness from 26 brix, and straight Zinfandel go off in 4 days as well from 26+ brix. It depends on if your yeast find something they like and go crazy. Protracted fermentations are much more prone to yeast stress and off flavors based on what I've experienced, and have been getting beaten into my thick skull in the UC Davis Oenology classes I'm taking. There are exceptions, and mead can certainly be an exception in many cases.

That being said, as mentioned in previous posts below (I have my profile set to stack most recent posts on top), you really have to mix your ingredients in correct proportions and dose correctly with the nutrient.

One point about adding nutrient with DAP past the 1/3 sugar break. At that point yeast are looking for amino nitrogen rather than the nitrogen derived from ammonia salts which are contained in most generic nutrient and energizers. Look for FermaidK or Fermaid 2133 which have little or no DAP, and contain a more balanced blend of nutrients.

Hope that helps,

Oskaar

archimedesbathtub
11-28-2006, 02:36 PM
Allow me to clarify...

The must was made and the yeast pitched on 10.07.07 per the details in my first post. The OG was 1.140. Activity was slow, but steady for the first few weeks. I did not have a 5 day fermentation on my mead, I was just saying that I have seen some of my beer fermentations go off that fast (just last weekend I had a barleywine go from 1.114 to 1.015 in 3 days!) Now, I understand that beer isn't the same as mead, but this long fermentation time was worrying me.

But now, I seem to have hit a brick wall. As of 11.27.06, the gravity is 1.050 (as it was on 11.21.06), and activity out of the airlock is one bubble every 2~3 minutes. The temp is at 72F, and the pH is ~5.

Assuming that my next move is to add yeast energizer and yeast nutrient, what types of energizer/nutrient and at what dose do I go with? Do I want to pitch more yeast?

Thanks for any help you can give.

-Chuck

Oskaar
11-28-2006, 04:02 PM
Arch,

Bring your temperature up to 72-74 degrees (K1 is a very temperature tolerant yeast and seems to like a 70 degree fermentation. Add some fermaid K at a rate of .5 gram per gallon and stir twice daily, don't aerate until you see the yeast taking off again, just stir to get it moving and into suspension.

Failing that, make a 1 gallon starter out of K1V and a must with a starting gravity of about 1.1xx. Let it go 24 hrs and add it in 1/2 gallon increments 4 hours apart.

Hope that helps,

Oskaar