Very slow fermentation and questions

fastenova · 12-28-2011, 06:05 PM

Hey everyone!

So I've been making mead with a buddy for several years with no formal research/knowledge and am finally doing some research and trying to improve our process and get better, more reliable results in a shorter time.

So far, our 5 gallon batches of mead with 10-12 lbs of honey take anywhere from 30-60 days to ferment down to the desired FG (depending on our target, .098-1.010). According to my friend, that was 'normal'. In reading online, it looks like that's super slow, and we should be seeing much faster drops in gravity, especially during the first half or two thirds of fermentation.

My current batch started out at 1.122 OG, with 15.75 lbs of honey - I'm shooting for a 14-15% alcohol content with this one. In the past 8 days it's gone from 1.122 down to 1.100. I have been degassing the mead some just by shaking/stirring and it seems to have improved the rate a little bit. But it still seems slow to me. This is with Lalvin 71B-1122 yeast.

First question is this: how quicklly should I see gravity drop? I know it depends on a ton of factors: original sugar content, yeast used, temperature, etc. But I'd like to know what's reasonable.

Second question: what can we do to improve our process to get faster fermentation? We warm our water to about 130 degrees, dissolve the honey, skim off solids that surface in the kettle, add a little acid via lemon juice, then cool down to approx 70 degrees. We rehydrate yeast (105 degree water, add DAP and yeast, let set for 20 min, add a little must, let set for 10 min, add equal amount of must, let set for 15 min, then pitch into carboy), seal it, and let it go.

Now again, this 'formula' or process is just what I learned from my friend, who had made it in the past. So I don't know about things like adding the acid (I have read that honey is already somewhat acidic?) but it seems like adding more nutrients would help, as would degassing more thoroughly/frequently.

Thanks so much for any replies, I love making mead but would love it even more if it fermented faster so we could get it on to the aging process sooner!

Cheers,
Aaron

fastenova · 12-28-2011, 06:06 PM

Also, I've seen conflicting information about adding oxygen during early fermentation to increase fermentation rate, versus keeping oxygen out because of undesirable tastes? I don't know if you want oxygen in your must early on but you want to keep it out after the midway sugar break?

Thanks!

**fatbloke** · 12-28-2011, 06:42 PM

Go over to gotmead forums index page. On the left is a yellow box of links, and one of them is their "newbee guide". It will pretty much answer all your questions for nutrients, aeration (its de-gassing when the ferment has finished, if you're stirring to get air/O2 into the must then its best described as aeration) etc.

Sorry I can't just post a link, but I haven't got that worked out on this phone yet.......

fastenova · 12-28-2011, 10:26 PM

It sounds like since we didn't aerate in the beginning the yeast may not have enough oxygen. I would like to aerate it now, is it still fine to introduce oxygen into the must at this point?

Also sounds like I do need to add nutrients (I've only added DAP in the past, including with this batch) so a more rounded nutrient supplement may work better, like the fermaid-o or -k or something similar.

Should I expect that to speed up my fermentation?

Thanks,
Aaron

**huesmann** · 12-29-2011, 03:49 PM

I think as long as you have active fermentation it's OK to aerate.

tweake · 12-29-2011, 06:47 PM

Quote:

Originally Posted by fastenova

This is with Lalvin 71B-1122 yeast........
add a little acid via lemon juice, ........
We rehydrate yeast (105 degree water, add DAP and yeast, let set for 20 min, add a little must, let set for 10 min, add equal amount of must, let set for 15 min, then pitch into carboy), seal it, and let it go.

whats your room temp?

i see a couple of problems straight up.....
71b does not like low ph so adding any acid is generally not a good thing as honey is already acidic and often around 71b's ph limit.
adding DAP to your starter is not good. you want to ad a little nutrient not DAP. ie add vitamins, amino acids, minor minerals etc.
it also sounds like your not adding any DAP into the must. thats probably why its taking so long. honey has very very little nitrogen for the yeast to feed on.

fastenova · 12-29-2011, 06:55 PM

Quote:

Originally Posted by tweake

whats your room temp?

Our must is staying at a consistent 64 degrees, which is well within the listed range for this yeast. I did just move it to my friend's place as he has more space, and it will be warmer there... Approx 70 degrees. It's a little warmer than I'd like but not sure if I have any other options as his ladyfriend like the house warm. =)

Quote:

Originally Posted by tweake

i see a couple of problems straight up.....
71b does not like low ph so adding any acid is generally not a good thing as honey is already acidic and often around 71b's ph limit.
adding DAP to your starter is not good. you want to ad a little nutrient not DAP. ie add vitamins, amino acids, minor minerals etc.
it also sounds like your not adding any DAP into the must. thats probably why its taking so long. honey has very very little nitrogen for the yeast to feed on.

Noted on the acid, we'll refrain from doing this moving forward. We weren't aware until very recently that honey was already pretty acidic. Thanks!

I just added some dissolved DAP to the must yesterday, and picked up some nutrient last night that I plan to add in the next couple of days (the fermenters are at my friend's place now).. The DAP has worked really well in making starters for us, it seems like the yeast takes off right away with a lot of activity in the airlock. But we'll start adding nutrient in there as well in the future, as well as some nutrient additions to the must after pitching the yeast (before the halfway mark, right?)

We will also make aeration a regular part of our mead brewing process for the first 1/3 of the fermentation.

Thanks!
Aaron

tweake · 12-29-2011, 07:28 PM

71b temp range is 59-86f. but you have to remember that it really slows down when close to 59. 64 is not far off minimum temp. good for taste but not for speed. 70 is about max you want to go taste wise and it will be a lot quicker than 64.
thats one curse with 71b is its a fairly tight temp range for mead.

you want the last DAP addition at about the 1/3 mark. (read up on SNA). after the 1/2 way mark yeast can't really use it all that well.

**broncobob71** · 12-30-2011, 12:39 PM

It seems like speed of fermentation is a sign of a great mead maker and therefore people don't like to talk about or admit to fermetation times that take longer than say 5 minutes. Personally I can't seem to get a 'fast' fermentaion time. Are mine normal or slow? That I can't tell you. I have asked and I get no response. My current batch is 15lbs for 5 gallons and d-47. For most of the fermentaion it has only dropped a point a day.

fastenova · 12-30-2011, 04:07 PM

Hey Bob, do you mean a point as in 1.081 to 1.080? That is pretty slow and seems as slow (or maybe even a little slower!) than ours which have taken as much as two months for a 12lb/5gal batch with no additives.

Good to know that if left up to their own devices, the yeasties won't necessarily haul arse.