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Nativepassion
01-19-2011, 10:25 PM
Can you aerate mid fermentation with a hand blender, or will it destroy the yeast cells?

MrMooCow
01-19-2011, 10:40 PM
Hrm..... I would say no it won't harm the yeast. The blades don't actually touch (not on mine at least), so there shouldn't be any scraping. The only concern I'd have is the blades aren't long enough to get the must mixed up fully. So you'd aerate the crap out of the top half, but leave the bottom half relatively undisturbed.

You won't /harm/ the yeast, but whether you'll really do any good is probably up for debate.

TDMooney
01-19-2011, 10:45 PM
You should be fine using a hand mixer, you wont hurt the yeast cells ... if anything you will make them happier by adding oxygen. I only oxygenate during the first 1/3 of fermentation though.

And I agree with MrMooCow , you probally wont reach the bottom of your fermentor ... but it's better then nothing

Nativepassion
01-19-2011, 10:59 PM
Thanks for the responses. I had thought about the layer issue, and figured I would slosh around with a big spoon after ward, but I wanted to make sure I wouldn't bust up the little beasties! :)

TDMooney
01-19-2011, 11:31 PM
All will be fine ;D

mmclean
01-20-2011, 05:31 AM
You say "mid fermentation", I would not aerate after 1/3 sugar break. Just gently stir to keep the yeast mixed into the fermenting mead.

Lost Tyger
01-20-2011, 11:12 AM
I only oxygenate during the first 1/3 of fermentation though.


Just so I can keep the details straight, when you say you only oxygenate during the first 1/3 of fermentation, are you referring to the 1/3 sugar break? Also, when determining when you have hit the 1/3 and 2/3 sugar breaks, this is done through hydrometer readings, correct?

I'm a bit of a details guy when it comes to these things; how important is it to hit the 1/3 break when adding the nutrients at that point? i.e., if I'm a day late, or a day early, or if I'm not within x.xxxx on the hydrometer readings of that break, will the whole thing go to hell? Just trying to get a grip on how sensitive the variables are....

TDMooney
01-20-2011, 11:31 AM
Yes you will want to determine the 1/3 sugar break using your hydrometer, as for the nutrients it is not a tentative schedule but these time lines are found and proven to be the most beneficial times to add nutrients (including oxygen) to your yeast for a healthy fermentation and quality end product.

As for your batch going to hell, it will most definitely turn out alright, but it will turn out better if you follow a S.N.A schedule ... people were making delicious mead way before hydrometers and thermometers were invented :)

YogiBearMead726
01-20-2011, 11:34 AM
Just so I can keep the details straight, when you say you only oxygenate during the first 1/3 of fermentation, are you referring to the 1/3 sugar break? Also, when determining when you have hit the 1/3 and 2/3 sugar breaks, this is done through hydrometer readings, correct?

Yup, first 1/3=up to the 1/3 sugar break. Basically, you want to aerate pretty religiously from the time you pitch up until the 1/3 break. This helps the yeasties build thick cell walls, shielding them from the rapidly rising alcohol levels, which helps them to survive (ie ferment) for longer than if no oxygen were provided. You're also correct on the "how to" of calculatingthe breaks. If you started at 1.108, or 108 Gravity Units, your 1/3 break is 1.072, or 36 GU (1/3 of 108 ) lower. This assumes that FG is 1.000 or lower. If you start higher than the yeast can finish, say, at 1.134, you have to do some extra math to determine an approximate FG based on the yeast's alcohol tolerance...but that's a bit complicated. Just one more reason to ferment to dry and backsweeten if residual sugar is desired...it's too hard to predict what the yeast will do. ;)


I'm a bit of a details guy when it comes to these things; how important is it to hit the 1/3 break when adding the nutrients at that point? i.e., if I'm a day late, or a day early, or if I'm not within x.xxxx on the hydrometer readings of that break, will the whole thing go to hell? Just trying to get a grip on how sensitive the variables are....

You'll find that yeast are pretty forgiving on this front. As long as you're close to the 1/3 break (before or after), it won't dramatically impact the flavors, if at all.

Nativepassion
01-20-2011, 12:17 PM
Yay! This thread has yielded some extra nuggets of wisdom.:)

Lost Tyger
01-20-2011, 02:31 PM
Yup, first 1/3=up to the 1/3 sugar break. Just one more reason to ferment to dry and backsweeten if residual sugar is desired...it's too hard to predict what the yeast will do. ;)

This is a point I've been wondering at.

For certain, I'm a strange bird, but I was somewhat puzzled when I discovered that the majority of people around here seem to be trying to ferement to dry. For me, dry equals not drinkable; can't stand the stuff.

I *think* I understand the concept of backsweetening; ferement the must until the beasties don't have any sugars left to ferement (Final Gravity 1.000 or less), then add some more honey (honey and water solution?) to add honey sweetness and flavor. I would think the thing to do would be to ferement to dry in a secondary fermenter (i.e., rack once, to get off of any lees), and then rack into a third ferementer and add the honey (honey & water) to taste, followed by aging. Would that be about right?

But a further question. Let's say that I start with a metric crap-ton of honey and an original gravity that is very high. I realize that this would be a difficult environment, because the yeast would likely be shocked by the high sugar level. But, let's say I got a good starter, got good aeration, and got the thing to start fermenting properly. At some point, as you mentioned, the yeast would produce enough alcohol to kill themselves off, and fermentation would end. And, as suggested, that may be somewhat difficult to predict; the beasties may tolerate more alcohol than advertised, or less, and so that sweetness level may be hard to predict, as would the final alcohol content. Also, determining when fermentation was finished would be difficult, and the mead would probably require me to stabalize it prior to botteling (Potassium Sorbate). I got that. But, if I found that the mead were too sweet, would it be possible to dilute it? That would be the equivalent to backsweetening, yes? So instead of backsweetening to taste, I could dilute to taste? The tradeoff being, I suppose, that by diluting it I would be reducing the alcohol content?

I just want to make sure I understand the tradeoffs before I do something really stupid....

MrMooCow
01-20-2011, 05:26 PM
By and large, I think you have it.

Here, I think, is the argument for why you run dry, then back sweeten - Two reasons. It's easier to get the ABV you want, and it's less stressful on the yeast. The last batch I made, my 14% yeast went to 17.3% before primary fermentation stopped. It also didn't want to stop. It kept trudging along, so it was real hard to stop. Everytime I added honey, it jumped back into production full force.

If you run it dry, it stops. Dead, done, deceased, no longer pining for the fjords. Then it's easier to stabilize before back sweetening.

Also, as mentioned, the lower starting SG is easier on the yeast. No matter how good your starting yeast, lower SG means healthier yeast. Healthier yeast means better booze.

Or so the argument goes.

Lost Tyger
01-20-2011, 06:34 PM
By and large, I think you have it.

Here, I think, is the argument for why you run dry, then back sweeten - Two reasons. It's easier to get the ABV you want, and it's less stressful on the yeast. The last batch I made, my 14% yeast went to 17.3% before primary fermentation stopped. It also didn't want to stop. It kept trudging along, so it was real hard to stop. Everytime I added honey, it jumped back into production full force.

If you run it dry, it stops. Dead, done, deceased, no longer pining for the fjords. Then it's easier to stabilize before back sweetening.

Also, as mentioned, the lower starting SG is easier on the yeast. No matter how good your starting yeast, lower SG means healthier yeast. Healthier yeast means better booze.

Or so the argument goes.

That is exactly what I needed to hear. I appreciate the feedback!

Chevette Girl
01-21-2011, 03:25 PM
I *think* I understand the concept of backsweetening; ferement the must until the beasties don't have any sugars left to ferement (Final Gravity 1.000 or less), then add some more honey (honey and water solution?) to add honey sweetness and flavor. I would think the thing to do would be to ferement to dry in a secondary fermenter (i.e., rack once, to get off of any lees), and then rack into a third ferementer and add the honey (honey & water) to taste, followed by aging. Would that be about right?


<snip>



But a further question. Let's say that I start with a metric crap-ton of honey and an original gravity that is very high.
Also, determining when fermentation was finished would be difficult, and the mead would probably require me to stabalize it prior to botteling (Potassium Sorbate). I got that. But, if I found that the mead were too sweet, would it be possible to dilute it? That would be the equivalent to backsweetening, yes? So instead of backsweetening to taste, I could dilute to taste? The tradeoff being, I suppose, that by diluting it I would be reducing the alcohol content?




OK, we're a little off-topic here, this could have been its own thread, but here goes anyway...

Lost Tyger, it's actually far more important to stabilize in the first situation than the second, because if you add more honey to a dry mead that isn't past the yeast's limit without stabilizing it, the yeast will keep on going and may reach a significantly higher alcohol level than they're rated for (as happened with MrMooCow - do a search on "step feeding" and you'll see why). And if you waited around to see if the SG has stopped changing, it won't have (like Mr MooCow, you'll keep adding honey, the yeast will keep eating it), and if you bottled right away, if you're lucky it will carbonate and pop the corks out and make a mess, if you're not, well, do a search on "bottle bomb", they're not funny.

The advantage to going for a really high alcohol level is that hey, it's potent. And eventually, yes, the yeast will stop on its own, either because they've hit a pH they can't work with, they've hit an alcohol concentration they can't work with or they've eaten all the sugar. And if it ferments out dry it's perfect for adding to something that didn't ferment far enough and is too sweet.

The disadvantages are that your yeast might not get that far, it might take years to age out to something you actually want to drink (that much alcohol can taste "hot" for a long time), you may end up with stressed-out yeasties causing off-flavours or odours because you're asking a LOT of them, and it can take for frigging EVER for them to finish the job because the more you ask of them, the harder it is for them to finish, and if you're not stabilizing, you want to leave it sitting in secondary for at least a year to make sure it's really, really done, and even that's no guarantee, sometimes all it takes is a temperature change and they can start up again years later. That, and hey, it's potent, you might not be able to drink much of it at a sitting without getting impaired enough that you're not really appreciating it anymore anyway ;D

The way that seems to work for a lot of folks around here is to aim for an alcohol content you want (generally something over 9% to be good for any kind of long-term storage) that's within your yeast's theoretical capabilities (most are in the range of 14% to 18%), and then you'll have a nice quick clean fermentation and your yeast won't be stressed out, then when there's no sugar left at all, let it clear a bit, stabilize with sulphite and sorbate, then backsweeten to a sweetness level you like, make sure the SG doesn't move over another month or so (sometimes they're persistent little buggers), then bottle it.

Distilled water added to a fermentation that stalled out too sweet could cause things to start up again, but would most likely just dilute the taste of your mead.

MrMooCow
01-21-2011, 04:16 PM
Just a clarafication Chevette.... My case of higher then expected ABV was not caused by step feeding. As you note, you can use step feeding to get higher then normal ABVs from your yeast. Mine was just caused by healthy yeast who got a bit gluttonous. I didn't add anything from the time I put it into secondary at the 1/3 to the time it topped out at 17%.

Lost Tyger
01-21-2011, 04:21 PM
<snip>


OK, we're a little off-topic here, this could have been its own thread, but here goes anyway...

Lost Tyger, it's actually far more important to stabilize in the first situation than the second


Yeah, sorry for that. Hope I'm not too far out in the weeds, I just normally think laterally (stretch from one topic to another) instead of starting a new topic.

I'm familiar with the concept of bottle bombs and, obviously, want no truck with that. So, realistically speaking, stabalizing is a vital step prior to bottling in all senarios? If you intend to backsweeten, you have to stabilize in order to guarentee you don't re-start fermentation of the newly added sugars, and if you have left any sugars in the mead (by not quite getting to dry), you have to stabilize to ensure that the simple changes in conditions don't re-start fermentation of the remaining sugars.

So, always stabilize, yes?

YogiBearMead726
01-21-2011, 06:33 PM
I recently bottled a few test bottles of my take on Oskaar's Mutiny on the Bounty Cyser. It stalled out around 1.034 and 16% ABV (below K1V-1116's listed tolerance). So far, it hasn't restarted in warmer conditions.

This should be taken as it is...an example of when the conditions of fermentation stalled an otherwise potent strain, and not a recipe for how to avoid stabilization.

So, to answer the question you asked, sometimes you don't need to stabilize. But to backsweeten, I would always anyway.

Chevette Girl
01-21-2011, 10:30 PM
I always stabilize if I backsweeten.

I don't usually stabilize anything dry unless I'm worried about a contamination issue.

I don't always stabilize still-sweet meads that have stalled out (again, barring contamination issues), but they are often in secondary fermentation for a year or more after the SG has stopped changing (mostly because I hate washing bottles:rolleyes:). And the only times this has bitten me has been when I didn't leave it long enough, fortunately in most cases I noticed it before a cork popped and I now have checks and balances for when I bottle things like JAO's (I use screw-top bottles and check them every few weeks till I know they're done for real and anything that's still sweet when I bottle it, I make sure I open the last bottle within a couple of weeks).

But then, I run the ragged egde and I won't recommend that risk to others :)

tuumi
01-23-2011, 10:47 PM
Back to the topic of the hand mixer. You can use it to degas too. I put it in the bucket every morning throughout the fermentation. After 1/3 break I don't disrupt the surface. Give it a quick blip and watch the CO2 rise. Be careful. Do it until the CO2 stops bubbling up. This gets the CO2 out and the yeast happy.

My handmixer does a great job aerating too. Hold it at the surface to agitate the hell out of it. Mix that air in. Tilt the mixer under the surface to really stir the oxygen throughout the bucket. Much less cumbersome that a lees stirrer and drill.

AToE
01-24-2011, 03:18 AM
I might actually try this for my next traditional, sounds like a fun method.