Question about Sulfites/K-Meta & Sorbate

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Pumpkinman

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I don't know why I just can't seem to wrap my head around this topic, but here it goes, please correct me if I am wrong.

Potassium metabisulfite:
After I left the Juice ferment with the yeast of my choice until it has reached the proper SG level (i've been checking the levels with a hydrometer every day or so, I've been happy with .998-.996, I should treat with 1/4 K-meta per 5-6 Gallons.

From what I've read, K-meta will not kill cultured yeasts, in my case, Lalvin 71B-1118 that I have used, only the foreign yeasts and yeasts present in vineyards and unwanted bacteria, plus it will help a wine to clarify and help to avoid white wines from getting brownish. I've also read that it can kill malolactic yeasts/bacteria, is this a good or a bad thing?

I was real confused so I just racked to the carboys figuring that I would try to learn this asap and apply it then, I realize that it isn't too late to add K-meta, I was apprehensive about adding it until I didn't see the airlocks "percolating" anymore, but if I am finally understanding this correctly, it will not harm kill the yeast I used for fermenting?

I know I need to get this done soon, more so now, after tasting a friends wine, a very good Chianti that he just puts into a demijohn and puts an airlock on and a year or 2 later drinks it, after having a gallon sit in my kitchen for 2 weeks, I opened the bottle and poured myself a glass, but when I smelled it, it was sour!
I don't want this happening to the wine that I have started!

I will need to take a little wine from each carboy to test the PH (I just ordered a Milwaukee PH55 Waterproof pH/ºC/ºF Tester), the TA, and the S02, so there will be plenty of room in the carboy to add the K-meta.

I assume that I need to dissolve the K-Meta in water, if so how much water, or does it matter, if not, do I just add it to the carboy and mix it?

Potassium Sorbate:
IF I've read correctly, I don't have to use Sorbate unless I plan on back sweetening a wine?

Sorry for such a long post, it gets a little confusing when I talk to several local home wine makers that add absolutely nothing and insist that their wine never spoils.
I would rather do this correctly the fist time, and as an IT guy, I understand that there are several ways to accomplish the same task!

I am open to any and all advice

Thanks in advance for the help!

Tom
 
Potassium metabisulfite:
After I left the Juice ferment with the yeast of my choice until it has reached the proper SG level (i've been checking the levels with a hydrometer every day or so, I've been happy with .998-.996, I should treat with 1/4 K-meta per 5-6 Gallons.

From what I've read, K-meta will not kill cultured yeasts, in my case, Lalvin 71B-1118 that I have used, only the foreign yeasts and yeasts present in vineyards and unwanted bacteria, plus it will help a wine to clarify and help to avoid white wines from getting brownish. I've also read that it can kill malolactic yeasts/bacteria, is this a good or a bad thing?

Before fermentation, k-meta is used to *stun/shock* native yeasts and bacterias - doesnt quite kill them, but definitely puts a damper on their living environment - giving you enough time to get your cultured yeast, started. Then your cultured yeast basically out-competes everything else, beating them to the nutrients.

After fermentation, k-meta is mostly used to keep oxidation (the browning) away, as well as keeping the environment harsh enough (along with acids and other things) that bacterias cant get a foothold

I was real confused so I just racked to the carboys figuring that I would try to learn this asap and apply it then, I realize that it isn't too late to add K-meta, I was apprehensive about adding it until I didn't see the airlocks "percolating" anymore, but if I am finally understanding this correctly, it will not harm kill the yeast I used for fermenting?

I know I need to get this done soon, more so now, after tasting a friends wine, a very good Chianti that he just puts into a demijohn and puts an airlock on and a year or 2 later drinks it, after having a gallon sit in my kitchen for 2 weeks, I opened the bottle and poured myself a glass, but when I smelled it, it was sour!
I don't want this happening to the wine that I have started!

So the wine is still fermenting? If you just racked it to a carboy... K-meta isnt something to add while fermentation is active, because it will affect your cultured yeast and will dampen their mood, potientially leading to off flavors of aromas that are produced from them being unhappy about it.. Fermentation could even stop altogether, only to start again when the levels of k-meta start to drop (and if that happens when the carboy is all topped up & you dont see it coming, kaboom! wine volcano)

As far as the friends Chianti, how old was the gallon he let go of? If its still aging, it could very well be sour (although 'sour' is a loose term) and be just fine.. Or could really have something wrong with it.

I will need to take a little wine from each carboy to test the PH (I just ordered a Milwaukee PH55 Waterproof pH/ºC/ºF Tester), the TA, and the S02, so there will be plenty of room in the carboy to add the K-meta.

I assume that I need to dissolve the K-Meta in water, if so how much water, or does it matter, if not, do I just add it to the carboy and mix it?

I usually dissolve it in some water first - doesnt take much and dont stick your face anywhere near it - because if you add it straight to a carboy theres the potential it could clump up and fall straight to the bottom.

Potassium Sorbate:
IF I've read correctly, I don't have to use Sorbate unless I plan on back sweetening a wine?

Right... And its recommended it add it alongside a dose (1/4 tsp per 5-6gallons) of k-meta, because the k-meta helps it be more efficient - unless you've dosed k-meta within the last 3 months, then you could "most likely" get away with 1/8 tsp k-meta instead of 1/4tsp
 
Perfect, thanks for the quick reply!

I'll wait until I don't see anymore Activity from the airlock, then I'll add the K-meta and rack it off any sediment.

Do you know of a digital S02 meter that doesn't cost a small fortune?
Thanks again!
Tom
 
The cheapest ones ive seen, by far, are the Vinmetrica units... Couple hundred bucks still, but not $600+ like most others ive seen
 
Perfect, thanks for the quick reply!

I'll wait until I don't see anymore Activity from the airlock, then I'll add the K-meta and rack it off any sediment.

Do you know of a digital S02 meter that doesn't cost a small fortune?
Thanks again!
Tom

Pumpkinman, Don't concern yourself with activity in the airlock. Use your hydrometer to determine if fermentation has finished. If the SG has dropped below 1.000 and is unchanged for 3 consecutive days then you can rack to a clean/sanitized carboy and stabilize your wine. Not seeing bubbles in the airlock does not indicate that fermentation is finished, always use your hydrometer.

LOUMIK
 
Pumpkinman, Don't concern yourself with activity in the airlock. Use your hydrometer to determine if fermentation has finished. If the SG has dropped below 1.000 and is unchanged for 3 consecutive days then you can rack to a clean/sanitized carboy and stabilize your wine. Not seeing bubbles in the airlock does not indicate that fermentation is finished, always use your hydrometer.

Bingo!!...
 
Loumik,
I agree, while in the fermenting pail, I used my Hydrometer daily until the SG was under 1.000 for a few days, then I racked into carboys, after two days I had a lot of Co2 passing through the airlocks, it's only been a few days in the carboys, 6 days so far, I didn't know if I should take another reading with the hydrometer seeing that the SG was under 1.000, and if I should add the k-meta.
Any ideas?
 
Take another SG reading and see if its the same as 6 days ago - wont hurt anything but if the numbers are the same then you'll know for sure that fermentation is done & you can move on in the process..

Some people will stabilize - add k-meta & sorbate(if backsweetening) - and then degas/clear..

I'm a bit backwards in that i like to degas before i stabilize
 
Thanks, I appreciate all of the info, it's been a long time since I was a newb at something, it's humbling!
 
try to be patient.
there is no extreme hurry to dose with kmeta and/or sorbate as soon as your sg
reaches 1.000 or lower. it won't hurt anything if your wine sits for a week or even longer after its done fermenting as opposed to rushing it a bit and prematurely interrupting the later stages of fermentation.
 

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