View Full Version : Question on slow fermentation/oxidation

02-28-2010, 11:07 AM
Hi all,

I've made a few batches over the years, all using natural methods, but hadn't brewed the past few years. I started a batch on 2/20 for 6 gallons, the fermentation was kinda slow (mostly 10 second intervals, with a few longer here and there) over the first week. The bucket had been put in the basement where it's not all that warm, probably around 48-52*F. After a week in primary, I split the batch into 2 separate 3 gallon batches. One went into a 3 gallon glass carboy as a traditional mead, while the other 3 gallons went into a food grade bucket w/~8lbs of strawberries and 2 vanilla beans. Ingredients are as follows.

For 6 gallons
15lbs local wildflower honey
store bought nutrient @ 1/2 tsp/gal
" " " " energizer @ 1tsp/gal
2 packets D47 rehydrated

PH (first time I've taken readings) was around 4.2-4.4
O.G. was around 1.100

When I was splitting the batch, the S.G. was around 1.072, but it was fairly chilly in the basement. I checked the ph and added a 1/2 tsp of calcium carbonate to raise it a little in both batches, as it the readings were a bit lower, in the ~3.3 range. Now both are sitting in the dining room, the traditional is chugging away @ 1 bubble every second and a half or so. The Mel is just sitting there. I have 3 main concerns as far as the mel goes..

1. The strawberries had been pureed then frozen, I had thawed them out (mostly) before racking, but there was still plenty which was very cold/partially frozen.. bringing the temp way down, did I make my yeasties go dormant?

2. The bucket is a food grade 4 gallon from a kitchen supply store (with matching lid). It doesn't have a rubber seal on the lid, so I figure I may be losing c02/getting oxygen via any leaks. (Used a hole saw bit and crammed a #7 stopper w/airlock)

3. Kinda falls partially under 2. Between racking and any possible leaks, should I be concerned about oxidation?

The mead is only around 3% abv by my calculations. After letting it sit in front of the pellet stove overnight to raise the liquid to room temp, there was still no airlock activity. After sufficient stressing, I rehydrated and pitched a packet of K1v killer yeast.

Any suggestions are greatly appreciated. I'm gonna wait it out, but wasn't sure if the oxygen exposure was particularly bad or good, considering there's a new yeast colony more than likely laying waste to anything fermentable in there.

Thanks a bunch


02-28-2010, 02:21 PM
Hi, SurlyFace! Welcome to "GotMead?" and welcome back to meadmaking!

Thanks for providing the details of your process thus far -- and for the description of your bucket fermenter. From my experience I'd say that #2 is your most likely issue. Especially when the buckets have no lid gaskets, they can leak copious amounts of CO2 so an airlock may show no bubbling at all but the must may be fermenting away happily. Always draw out samples for hydrometer or refractometer testing periodically during primary fermentation. The change in specific gravity should be your only reliable indicator of the speed of your fermentation.

I don't think that #1 should be an issue in this case, partly because most musts, if started too cold, will begin to ferment when warmed back up - the only exception to this is if you cold shocked your yeast so severely that it is damaged or killed. Since D47 likes to work at cooler temperatures, this is pretty hard to do with that yeast. Also sometimes D47, especially at lower temperatures, will slow to a crawl and ferment very slowly - but fermentation will proceed. The K1V addition was probably not necessary, although it won't hurt anything - you'll just have a K1V - D47 product rather than a monoculture D47 product. Both D47 and K1V produce the "killer" proteins, and both have natural immunity to the toxin, so you'll end up growing both cultures in your must.

Also, #3 should not be a concern until you've reached at least the 1/2 sugar break (the point where half of the fermentable sugars are consumed), since wine yeast actually need a little O2 early in the fermentation to develop new cells and get the colony going as strongly as possible.

Finally, if you haven't read the NewBee Guide (a link is over on the left side of this page), you should. It will acquaint you with lots of new meadmaking process knowledge that has been developed over the last 10 years or so. Meadmaking before that time was kind of a stepchild of beer brewing, so lots of processes and techniques that are applicable to beer (such as keeping all oxygen out right from the onset of fermentation) which were once thought of as gospel in meadmaking, are now no longer common. We meadmakers have learned a few things by experimenting on our own! ;)

Dan McFeeley
02-28-2010, 03:15 PM
Here's a pdf file on Lalvin D-47, of note, low end of the temperature range is 15 C/59 F, and there is a warning against cold shocking the yeast.


Looks like you're on the right track, maybe a bit more patience will see both batches through.

Keep us posted!


02-28-2010, 10:19 PM
Thanks a bunch guys. Looking forward to taking some hydrometer samples as I punch the strawberry cap back down. : )

03-01-2010, 10:43 PM
Today I went to punch the cap down at around 6pm EST, took a hydrometer reading.. 1.008! I haven't grabbed a second 3 gallon carboy as of yet.... (King procrastinator). So I sanitized a 5 gallon carboy, purged it with a 20oz c02 bottle, having cracked the globe valve a little, for ~45 seconds. Racked the mel into the carboy, purged again with the valve very slightly cracked open. Let it leak into the headspace for another 20 seconds or so. Sanitized stopper and airlock fixed, wrapped a blanket around it and set it down in the dining room. It's chugging away at 1 bubble every 2-3 seconds. The traditional is still happily hammering away at 1 bubble every second.

03-01-2010, 11:01 PM
Excellent! Congrats on the successful ferment -- and you'd better pick up another one of those smaller carboys for long term aging. ;)

03-03-2010, 07:48 PM
My LHBS said they are expecting a 3 gal later in the week. If that doesn't pan out, luckily another LHBS is having an open house this saturday... hehe. I haven't taken any gravity readings or disturbed it at all, airlock is bubbling once every 30-45 seconds. So I want to get this 3 gallon jug thing resolved soon.

Should I even bother with ph level anymore? Seeing as how the yeast has already wiped out most of the sugar?

Thanks again


03-03-2010, 09:52 PM
I think that you're good with the pH as-is. I would only consider an adjustment if the mead tastes "flat" (as in not enough acidity) or too sharp (too much acidity).

03-14-2010, 02:33 PM
A quick update.. On 3/6 I racked the strawberry mel into a sanitized then purged 3 gallon carboy. There had been minimal airlock activity and the S.G. was 1.002, so I added a stopper and airlock, gave it a day then added a solid stopper and set it down in the basement (in the box the carboy came in, with a few strategically placed boards so no light can get in).

Today I racked the other 3 gallon batch (traditional) into a sanitized/purged 3 gal carboy and reattached airlock -it had been bubbling once every 30 seconds or so.. I didn't take any gravity readings, having racked right down to the lees. Will take one in a few days when checking up on it.

Since the 6 gallon split batch I've started a JAO (1 gallon) on 3/5 and today I started a 5 gallon batch using 12lbs of blueberry honey from The Bee Folks. I did have a question or two on this new batch, but that'll go into the general recipe discussion forum..Where it makes much more sense to post such questions.