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View Full Version : How long to aerate during SNA?



baconfatlabs
06-20-2014, 02:23 PM
Hi everyone, long time lurker first time poster....

I started making mead back at the end of March, and now have two successful five gallon batches that are currently aging. The first is a plain mead that I made with 15 pounds of Clover Honey, 4 gallons of water, Lalvin D47, yeast nutrient and energizer. The second was a melomel that I made with 20 pounds of Clover Honey, 3 quarts of organic black cherry juice and 1 quart of organic currant juice with only 3 gallons of water, and the same Lalvin D47. Neither of the juices had preservatives. During the melomel ferment, I discovered (learning every day!) that the yeast was way out of it's comfort temperature as my house is 78 degrees and the range only goes up to 68. Despite this, it still turned our well, however, I will be switching to Lalvin 71B with that in mind because it appears to go up to 86 degrees in range. My house doesn't get down below 68 degrees at any time of the year (I'm in Texas, and not overly fond of high heating or cooling bills) and even though things have come out very well, I'm a believer in things being in an "optimal" environment for use.

Anyhow, on to my question. When I ferment my next batch, I'd like to try doing a staggered nutrient addition. With the first two, I just added them during the initial yeast pitch (separately, though). I got a strong ferment for 3 weeks and then it tapered off. From what I understand, SNA will cause it to have a strong ferment until it stops altogether. I also have a harsh carbonation that, according to what I see, will just need to age out of it, but also something that can be mitigated with SNA and aeration. I see that it is a good idea to aerate when you add the nutrients each time, and I have a Mix-Stir paddle for that. The thing I am a little confused on, is how long to aerate once you add nutrients. Is there a bare minimum time, is there a such thing as over-aerating when you add your nutrients? I can't seem to find anything conclusive on the matter.

By the way, thanks for having me here. Even as a lurker, it's been a lot of fun. -Eric

fatbloke
06-20-2014, 02:58 PM
Well its routine to aerate until the 1/3rd sugar break. Once or twice a day. Some even use pure O2 through a stainless airstone.

its worth remembering that you will need to have a bit of a plan as to the start gravity and where you will add the nutrients as its feasible that it could ferment quickly or slowly, and that you will need to have the the doses ready etc.

Always aerate first then add the nutrient dose, otherwise you can get some mega foam eruptions especially at the start.

if you look at my blog (linked in my sig line) the top link is for an article by Ken Schramm that explains about nutrient provision etc.....

baconfatlabs
06-20-2014, 06:13 PM
Hi fatbloke, thanks for responding, and I will definitely check out your blog when I get a moment. My question wasn't so much "how often" do I aerate, as that information is pretty abundant. I'm wondering more or less, how long do I aerate. As in, when I stick the mix-stir in the bucket, how long do I run the drill for? Do I just go until it's not fizzing anymore, or are there any tell tale signs that it is degassed sufficiently? I do realize that this is probably a no-brainer for most people, but I still lack the experience since I've only done two batches, and I'd rather learn from others than have to learn from my mistakes, if that makes sense.

Thanks! -Eric

Ironpapa40
06-21-2014, 01:13 AM
Depending on how fast your ferment is going and how many times a day you degas, you will have varying amounts of gas in your mead. Since you don't really know until you start stirring, it's a good idea to put your stirrer in without the drill running and give a good stir. Then start your drill slowly. You can avoid a potential eruption this way. Then just run it until the majority of the foaming stops. Once again, time is going to depend on how much gas is in solution. I mix until it looks like the mixing is creating the bubbles as much as the mead. So there's no set time exactly that I've ever heard of anyway.

fatbloke
06-21-2014, 02:30 AM
In a wind/breeze free environment, there's a theoretical possibility that once the batch has stopped giving up gas, that you could still have a blanket of the gaseous CO2 as it's heavier than O2/air.

I like to fan the CO2 away so I'm confident that some O2 is getting incorporated.

There is, from memory, some info where peeps have tried to put it on a more scientific footing - timings, pressures and different gauge stainless airstones etc, but I can't remember is there was any evidence as to what was best or even if it was just more successful or just some sort of "good idea"........

Ergo, no set timing as far as I'm aware.......

baconfatlabs
06-21-2014, 02:33 AM
Ah, that makes sense, thanks. Based on that, I think I will just take a visual cue from the mead that degassing is accomplished once the foaming had gone, I just didn't know if/when I would approach diminishing returns by aerating it past a certain point to feed more oxygen to the yeast. Due to the nature of my schedule, I likely would only be able to degas it once a day when I touched it to add the nutrients during SNA. I also really fear contamination so I am hesitant to touch it more than necessary.

fatbloke
06-21-2014, 04:40 AM
Well, invariably due to work, I can only aerate once a day, and I don't really care whether it's morning or evening. If it's in a bucket I'll use an electric whisk or stick blender (I try not to mash the hell out of any fruit in there, as the pulp is a pain to deal with).

Generally 3 to 5 minutes. Once I hit the 1/3rd sugar break (I routinely test before aerating), I give it a last whizz and then airlock it off and wait for the bubbles to stop. This varies only if I'm doing some step feeding, then I'll test before and after the honey addition etc......

Oh and my blog is just my ramblings, but the links I've included are mostly quite helpful (mostly to me, but there is some excellent stuff there - hence why I pointed you toward Ken Schramms paper on yeast nutrition etc).........