Concern about 71B, cyser and sorbate.

[altodiva]

Howdy. I'm planning on making a cyser at some point. (just finishing up one made with Lalvin D47 that is turning out awfully tart and sour..... will be playing around with backsweetening and time for this one!) I'd like to try Lalvin 71B on the next batch to try and take some of the malic acid edge off.

I plan on sulfiting the fresh cider with K-metabilsufate (the apples were pressed at a big party and I wasn't too convinced of the cleanliness of the process!)

After fermentation, I plan on stabilizing the young cyser first with potassium metabisulfite and then with K-sorb. Herein lies my question:

My understanding is that 71B metabolizes malic acid into lactic acid. So does this put me in danger of creating the "rotten geranium" stink when I add the sorbate?

Thanks in advance for any help with this!

 

[Arpolis]

It does have that potential but the great thing is a little aeration & aging and that will go away. Just pitch the stabilizers and if the smell kicks up then hit it with a wine whip on a drill for a couple minutes and then let it age. After a little while that smell should be all gone.

 

[fatbloke]

The production of geraniols comes when the sorbate gets munched.

The problem only arises if you only add sorbate, it's why you normally use both sulphite and sorbate, which normally prevents this.

The 71B only metabolises about 30% of the malic acid anyway, plus the presence of the sulphites will also prevent MLF (MLF won't happen if the sulphite concentration is over about 20 ppm - 1 campden tablet per gallon provides about 50 ppm).

The biggest possible hazard with 71B is that of autolysis. It's not a yeast for trying "sur lie" or "batonage" ageing. It seems that the recommendation is to make sure the mead is racked off the gross lees between 1 and 2 months after the end of the fermentation stage.

I don't know if there's any issue with fine lees, but with the above in mind, it may be worth just racking off the gross lees and then hitting it with finings, then racking off the fine lees and then ageing it clear.