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aczdreign
05-13-2012, 12:09 AM
I'm trying to duplicate what I did here: http://www.gotmead.com/forum/showthread.php?t=19660

The changes that I made were that the starting gravity of this batch was 1.154 instead of 1.134, and the yeast i'm using is Lalvin bourgovin rc 212 instead of 71b-1122.

I started the batch on 5-3, and have checked it a few times since then (I'm out of town for work a lot this month), and the brix % is only down to 25, from 35 starting.

It's going REALLY slow in comparison, is it because of the slightly higher initial gravity? I added an extra dose of fermax and energizer on 5-7, when the brix was at 31.

So basically, the Brix content schedule has been
5-3: 35%
5-7: 31%
5-12: 25%

It seems fairly stable, but very slow...how can i remedy this?

EDIT: This mead was started the same day, same relative amount of nutrients, same yeast. It's down to 27 to 14.
http://www.gotmead.com/forum/showthread.php?t=19797

Chevette Girl
05-13-2012, 12:54 AM
Well, for starters, that was a "significantly high" starting gravity, not "slightly higher", 1.135 is about as high as I'd ever consider starting a mead if I wanted it anywhere near finished, if I wanted to make something really strong, I'd have started lower and step-fed it once it had eaten most of the honey. The higher you start, the more stressful it is on your yeast because of the osmotic pressure from the high-sugar solution you've put them in. If I'd seen 1.154 on my hydrometer, I'd have watered it down to 1.135 at least before pitching.


... and RC-212 is kind of a whiny-pants nutrient hog, it would not have been my first choice for such a high grav start, I'd have gone with K1V1116 or EC1118... and you don't mention how you pitched in either this thread or the original, did you rehydrate? Use go-ferm? make a starter?

I'd expect your Love Potion one to be a quicker, cleaner fermentation because it's in a better SG range for yeast, 1.120 isn't too much to ask, but 1.154 may well be...

To remedy this? Honestly if it were in my carboy, I'd strongly consider diluting it a bit. And if the whiny-pants yeast continues refusing to do its job, I'd re-pitch with K1V using an acclimated starter.

That's my $.02, anyway.

aczdreign
05-13-2012, 02:48 AM
Thanks for your advice.
As far as preparing the yeast, I follow Lalvin's instructions which are basically add warm water, stir, wait 15 minutes, stir, and then pitch.
To add to this, I think I was somehow entering the wrong numbers into the SG calculator, because I swear to you I'd seen it at 6% or so ABV earlier, but now it's telling me 11%.
If it's at 11%, I'm tempted to leave it as-is. If I were to dilute it, being that the SG is now about 1.03, how much water would I need to add? How would I calculate the alcohol dilution?

TAKeyser
05-13-2012, 11:15 AM
Thanks for your advice.
As far as preparing the yeast, I follow Lalvin's instructions which are basically add warm water, stir, wait 15 minutes, stir, and then pitch.
To add to this, I think I was somehow entering the wrong numbers into the SG calculator, because I swear to you I'd seen it at 6% or so ABV earlier, but now it's telling me 11%.
If it's at 11%, I'm tempted to leave it as-is. If I were to dilute it, being that the SG is now about 1.03, how much water would I need to add? How would I calculate the alcohol dilution?

a SG of 1.154 has the potential for almost 21% abv and the 212 you pitched is rated for 16% so even if you do somehow get the yeast to finish you are going to have a very sweet mead.

fatbloke
05-13-2012, 12:10 PM
RC-212 is a nutrient hog, so it could be that, or the high gravity might be causing a bit of osmotic shock to the yeast, or its in need of more aeration for yeast development, or maybe the high gravity is causing pH issues......

That's what's going through my head and what I'd be looking at, were it mine!

Chevette Girl
05-13-2012, 12:43 PM
Thanks for your advice.
As far as preparing the yeast, I follow Lalvin's instructions which are basically add warm water, stir, wait 15 minutes, stir, and then pitch.
To add to this, I think I was somehow entering the wrong numbers into the SG calculator, because I swear to you I'd seen it at 6% or so ABV earlier, but now it's telling me 11%.
If it's at 11%, I'm tempted to leave it as-is. If I were to dilute it, being that the SG is now about 1.03, how much water would I need to add? How would I calculate the alcohol dilution?

Well, if you started at 1.154 and got it down to 1.030, that's 16% so anything further will be a bonus. Congrats. You made whiny-pants RC-212 do its job with a minimum of fuss :)

Now, if you don't like it that sweet, you might consider watering it down to a level you're happy with (If it were mine and I was aiming for a finishing gravity around 1.010, I'd maybe drop it by a SG of 0.010, because it might well ferment a little more on its own).

TAKeyser
05-13-2012, 12:51 PM
I'm not sure you are reading your Hydrometer right. You're saying your at 25 Brix in one post and the same day your Gravity is at 1.030 and those numbers just don't match up.

aczdreign
05-13-2012, 12:59 PM
I knew it was going to be sweet, that was why I put what I thought was a little extra honey into it and used the yeast I did. Granted that 'little extra' was a lot more than I had intended, but I measure all of my honey from gallon containers and usually eyeball 1/3 gallons, etc. I've got no problem with the taste (a little yeasty at the moment), I was just wondering if it seemed exceptionally slow to you all.

I'm using this refractometer calculator:
http://onebeer.net/refractometer.shtml

entering my numbers into the bottom, starting brix was 35, final brix is 25, comes up with 1.08, 11% abv.
I've been using the same calculator forever now, and I'm really not sure what I've been doing for the past few days to get such different numbers in my last few posts.

Being that RC212 can only withstand 16% abv, which should be 19-20% brix down from 35, and it's already at 25, I may just see how it works out if I leave it alone and just continue the aeration schedule. Is this a bad idea?

TAKeyser
05-13-2012, 01:11 PM
Starting at 35 Brix and being at 25 Brix right now you are sitting at 6.5 % abv. I've triple checked my figure doing it first in my head, than looking at my hydrometer and finally inputting it into the calculator here on Got Mead and my brew calculator and they all say the same thing. Obviously you want a sweet mead so that means you need to get it down to around a 5 Brix.

Switching over to Gravity readings:
35 Brix = 1.150 Gravity (20% abv potential)
25 Brix = 1.104 Gravity (you sit at 6.5% abv)
8 Brix = 1.030 Gravity (yeast tolerance at 16% [according to Lalvin)
5 Brix = 1.020 Gravity (would give you an 18.5 % sweet mead)

aczdreign
05-13-2012, 01:18 PM
SIGH!!

Okay, so why are the numbers so different between the two calculators???

AND, have ALL of my calculations been WRONG up until this point???

I just found the gotmead calculator, used it, and got the same numbers you got. Very frustrated.
The onebeer calculator shows 35->30% giving 6% abv, while the gotmead calculator shows 35->25 as 6% abv.

Going back to the #7, Love Potion, it's showing 6% abv on gotmead, and 12% on onebeer. Looks like everything is whacked out with the calculator I've been using, but I don't think it was always that way, because I had medson at one point help me out in using it, and I dont remember this problem then.

TAKeyser
05-13-2012, 01:25 PM
something in the one beer calculations is wrong. I just the numbers don't seem to be matching up. When I put 25 brix in the top calculator it gave me the correct reading, but when I used the bottom calculator and entered 35 at starting and 25 as ending it gave me a final gravity much lower than it should have been.

aczdreign
05-13-2012, 01:26 PM
Well....
Thanks for clearing that up. I guess I'll have to revise all of my old notes and labels now.

Chevette Girl
05-13-2012, 01:28 PM
Being that RC212 can only withstand 16% abv, which should be 19-20% brix down from 35, and it's already at 25, I may just see how it works out if I leave it alone and just continue the aeration schedule. Is this a bad idea?

I would not aerate this any further, it's WAY past any sugar break where we usually stop aerating, the yeast don't need it at this point and all you're doing is risking oxidation...

...unless, like me, you like the taste of oxidation (sherry) and are trying to get it intentionally.

aczdreign
05-13-2012, 01:33 PM
Honestly, I'm so frustrated right now that I'm almost incapable of thinking straight. I'm going to go walk my dog and maybe when I get back I'll fool around with this some more.

So, how much dillution would you all recommend? You think I could stretch it up by another half gallon or so? I don't know how to do all this once it's started to ferment.

I'm going to throw another question in here, just because I lack the will to start a new thread.

I added campden and potassium metabisulfate last night to a batch of muscadine that's abot 2 years old. The airlock has been DEAD on this for a long, long time, but now that I added the stabilizing chemicals, it's bubbling like crazy. Is this normal?

TAKeyser
05-13-2012, 01:38 PM
I added campden and potassium metabisulfate last night to a batch of muscadine that's abot 2 years old. The airlock has been DEAD on this for a long, long time, but now that I added the stabilizing chemicals, it's bubbling like crazy. Is this normal?

This bubbling is normal, but Camden tablets are Potassium Metabisulfate (sometimes Sodium Metabisulfate depending on brand) so this really isn't going to stabilize. It will temporarily halt (and help prevent oxidation), but a proper stabilization is Campden (or Potassium Metabisulfate) and Potassium Sorbate.

aczdreign
05-13-2012, 01:44 PM
Once again, the advice given me at my local brewing store is wrong.

Again, thanks for clearing this up, I guess I'll go buy some MORE chemicals on my walk.

So have I ruined my mead by adding basically double campden?

TAKeyser
05-13-2012, 01:47 PM
So have I ruined my mead by adding basically double campden?

I'm guessing that you'll be fine.

fatbloke
05-13-2012, 02:40 PM
Presuming that aczdreign is in the US ? Well campden tablets there are generally potassium metabisulphite, which is advantageous, because over doing it is less likely to be a problem, whereas the sodium meta' generally available here is more likely to give a metallic/salty hint. So should be ok if its k-meta in the campden tablets.

As for the old batch starting to bubble with the addition of the stabilising chems..... that's down to the batch having dissolved CO2 in it, and the stabilising chems have provided nucleation points for the CO2 to grab onto, forming the bubbles and triggering the airlock.

Look up de-gassing methods, and you'll not only stop this, but it can also reduce the slight sharp taste that can come from carbonic acid a.k.a. dissolved CO2

aczdreign
05-13-2012, 03:49 PM
Thank you all very much for your help.

An incorrect SG calculator was NOT the first thing I wanted to see when I got out of bed this morning, and it all seemed horribly confusing, but a nice walk in the sun does wonders to clear the mind.
So, now that I need a new calculator, I've been looking at the one here on gotmead, and I can find ABV with my brix reading, but how do I go about getting an actual SG? Medsen had explained to me before regarding the calculator on onebeer something about the added alcohol in the solution changing the SG formula, which is why I was using the bottom of that calculator instead of the top. Problem is, the calculators here at gotmead aren't as complete as that one is, showing (albeit incorrectly) SG, ABV, ABW, and IoR from a brix percentage.

Fatbloke, I actually added a campden tablet and a dose of pot meta into just about everything last night, and I am in the US, so I guess I should be ok there.

So, back to the slow traditional, how much water would I want to add to it to give the yeast a better environment? According to our previous discussion, the SG is below the 1.135 maximum we had discussed...Should I expect to see a boom in activity or does it need dilution?


EDIT: As a sidenote, if you look back at my post from 2am, I said I couldve sworn that the onebeer calculator was showing me 6% the first time I measured it (11pm), which is why I made this thread. As I was writing the 2 am reply, it was showing me 11%, which is why I was suddenly considering leaving it alone. Later on, TAKeyser calculated my progress at 6.5%, as I had initially thought I'd read on the onebeer calculator (but had attributed to typo or something).
Am I making any sense here???
I know it sounds crazy, but its almost like the coding on the calculator changed during that time.

Chevette Girl
05-13-2012, 04:04 PM
I always get a couple days worth of airlock activity when I use campden tablets and potassium sorbate on a must.

Ok, back to the original issue, when you said

If it's at 11%, I'm tempted to leave it as-is. If I were to dilute it, being that the SG is now about 1.03, how much water would I need to add? How would I calculate the alcohol dilution?

did you mean the SG is now 1.130? (sorry, I don't speak Brix, I haven't taken my refractometer out of the package yet, and this is making me less and less likely to want to even bother ;D)

Heh, I now think I'm as confused as you are... Looking at your later posts, if it's only at 6% of a potential 18%, then yeah, at least one more aeration wouldn't be a bad plan, and I'd dilute it to drop the SG by .020, since the initial must was about that much higher than it should have been. And how SG corresponds to Brix doesn't appear to be linear, so I don't know how to calculate it for you... and with SG, I know how to figure out how much the dilution will have affected the alcohol content but I don't know how to do it with Brix. But if keep very careful notes on the volume you started with and the volume you added, the dilution can be figured out.

aczdreign
05-14-2012, 01:57 PM
thank you again.

Nathan K
05-14-2012, 04:02 PM
The gas release could be dissolved CO2 that found a way to escape now that something new was added but it could also be sulfur dioxide gas which I would kind of expect with a sulfite addition.

Given that it is already 2 years old, is there a reason why you want to stabilize? Are you planning to sweeten it or something? If not, I'm not sure why a sorbate addition would be needed at all. Sorbate additives are used to prevent any remaining yeast (which would be very little after 2 years) from starting a new fermentation. It doesn't kill the yeast but makes it so they can't get going again.

Campden tablets in the US could be either Sodium or Potassium metabisulfite although the Sodium Metabisulfite is on it's way out the door. That said quite a few homebrew shops and distributors are still selling the sodium based ones. I don't use Campden tablets at all because buying straight potassium metabisulfite is not only cheaper, it's also easier to use because it doesn't require crushing.

aczdreign
05-14-2012, 04:08 PM
Okay, so the brix is still at 25%, which according to the top half of the onebeer calculator equates to 1.107 SG.
It's also showing that 21% brix should create a SG of 1.088, which is .019 less than it currently is, which should take care of that initial ratio problem.
So I'm going to add spring water to bring my brix reading down to 21%, and then hit it with one more dose of nutrient and energizer.

Added one half gallon spring water. I overshot it a little, the Brix is now at 20%, which should give a SG of something like 1.083, give or take a little for the alcohol already in the solution.

EDIT: checked all values according to the gotmead calculator and everything seems correct. I already THINK I'm seeing more activity in the airlock, but it may just be in my head.

aczdreign
05-14-2012, 04:10 PM
Nathan, I really just wanted to make sure that this batch wouldn't blow off the corks from the bottles. I was actually planning to sweeten it, but after having a few friends taste test it, that plan changed.

You think i would be alright just bottling it, then?


EDIT: I just figured out that I canset the gotmead calculator to brix, enter brix values, then change the dropdown box from brix to SG, and it seems to convert it for me automatically. That's a huge help.