Unintended fermentation

[CMcPherson]

I have a 5 gal carboy filled with 4 gals of store-bought pasteurized juice waiting for my yeast to arrive.
I figured that since the juice is pasteurized it would be okay for a few days.
Well... lo and behold, the airlock is working!
I'd rather use The Nottingham yeast that I have coming.
Can I use K-Meta and Potassium Sorbate to assure that my Notti takes hold or is it too late now that it's active?

If yes, how much of each per gal.?

 

[gratus fermentatio]

Do NOT use sorbate. It will inhibit the Nottingham yeast. Use sulfites only, 1 campden tab/gallon should do it. Be sure you dissolve them in a little water before adding to the juice. I just put the tablets in a ziploc bag & crush 'em with a rubber mallet, then add about 1/4-1/2 a cup of warm water to the bag & swish it all around till the powder dissolves, then just pour into the carbouy. You'll want to stir it in gently & refit the airlock. Wait 12-24 hrs before you pitch the Nottingham.
Regards, GF.

 

[Maylar]

I you have powdered K-Meta, 1/4 TSP for 5 gallons is the typical dose. I would as a minimum rehydrate the Notty, and if possible make a starter to give it the best shot at taking over.

 

[lumpher]

Since fermentation is happening before you added yeast, wild yeast has already taken hold. Taste it and see, but you're probably on your way to vinegar. It's too late to add k-meta and stop what is happening.

 

[adiochiro3]

Since fermentation is happening before you added yeast, wild yeast has already taken hold. Taste it and see, but you're probably on your way to vinegar. It's too late to add k-meta and stop what is happening.

This is not true. Follow what GF said and you will be fine unless your juice has fermented for days. Even then, you will still have cider rather than vinegar because you need alcohol and acetobacter -- which your air lock is keeping at bay.

 

[CMcPherson]

Thanks all.
I've been told that Sorbate needs to be used in conjunction with Sulfites.
Is this not true?
I'll be using powder instead of Camden tabs.
I'll use a starter. I have my stir plate and 1500ml beaker ready to go when my yeast gets here.

 

[Maylar]

That's a different application of sulfites. At this level you're looking to kill bacteria and wild yeast. No sorbate. At the level of a finished product where we look to stabilize a fermented cider or wine, sorbate will stop the reproduction of yeast and it works best in the presence of sulfites so we use both.

Sorbate in primary would be like trying to ferment preserved juice. Bad idea.

Cultured ale and wine yeasts have resistance to sulfites, so it should only affect the wild stuff in progress.

 

[CMcPherson]

Now I understand... thank you.