First malolactic fermentation

[nicklausjames]

I purchased some frozen cab sauvignon grapes from vino superiore. So far I have been happy with the quality.

Anyways, I am doing my first malolactic fermentation and I'm doing it in a 5 gallon glass carboy. I started it after pressing and racking off the gross lees.

The first 2 days it was very vigorous with lots of little bubbles. Now is day 4 or 5 and it seems to hav slowed to the point it is not recognizable to the naked eye unless I shake the carboy. I am wondering if this is normal or if something is wrong. When I shake the carboy the little bubbles appear for probably 30 seconds to 2 mins.

If there is an issue with the malo ferm stopping, what can I do to restart it.

Finally, I have read that I need to stir the remaining lees up twice per week. I am concerned about oxidation and/or contamination since my SO2 levels are so low. Is it adequate to just vigorously shake the carboy or must I remove the airlock and stir with a stirrer?

 

[Boatboy24]

MLF can often show no outward signs, even though it's progressing just fine. A couple questions though:

What strain of bacteria are you using?
What is the temp,of your wine?
Do you know your ABV and pH?

You should stir once a week or so - the airlock being off for just a couple minutes shouldn't pose any risk.

 

[nicklausjames]

I used wlp675 from whitelabs. Ph was 3.43 and abv 13-14. I don't know the exact temp but since my basement is in the 50-60 degree range I put a space heater nearby and tied a thermometer to carboy. Thermometer ranges between 70-80 depending on whether heater is on.

 

[Pumpkinman]

Nickausjames,
WLP675 is a finicky strain, White Labs recommends pitching is (co-fermenting) when the must reaches a gravity of approximately 5 brix.
Your Ph is fine for this strain, as far as temps, White Labs states that 60F is the recommended low, however this strain can tolerate down to 55F, I recommend keeping it at a happy temp of 70°.
I think that the temps are causing it to slow down. I also put 4, 6 gallon carboys in my cellar in October, I pitched MLB VP41 thinking that the warm temps would get the MLB established and working strong before the cooler temps showed up....in theory, it was a great plan, in reality, Malolactic fermentation came to a stop, I have just enough heat on the carboys to keep the MLB happy, but MLF is still rolling along after 5 months.
Airlock activity, or lack of, is not an indication that MLF is active or stopped, most times, you won't see any major indications, just a few tiny bubbles up the side of the carboy. I'd wait a week or so and run a chromatography test, this will put your mind at ease and at the same time show you just how visible MLF can or cannot be.
If you need any help, don't hesitate to ask.
Tom

 

[nicklausjames]

Thx so much everyone! Is there a suggested method for "stirring" the lees. Should I open the carboy and stir with stirrer or simply vigorously shaking the carboy enough?

How careful do I need to be with oxidation/introducing bugs?

 

[Pumpkinman]

Open the carboy and stir with a stirrer.

 

[Boatboy24]

Open the carboy and stir with a stirrer.

Sanitize the stirrer first.

 

[sdelli]

I used wlp675 from whitelabs. Ph was 3.43 and abv 13-14. I don't know the exact temp but since my basement is in the 50-60 degree range I put a space heater nearby and tied a thermometer to carboy. Thermometer ranges between 70-80 depending on whether heater is on.

wlp675 is a hard strain to manage! I highly suggest next time using a different strain.


Sam

 

[Turock]

And do not stir it vigorously--stir it very gently as all you're doing is getting the MLB back in contact with the wine. Stir twice a week.

MLB is not very active--pay no attention to lack of bubbles. Remember--this is a BACTERIA--not a yeast.

 

[Turock]

I agree with sdelli---we always use Bacchus because it's not fussy and ALWAYS goes to completion with no problems.

 

[REDRUM]

Are there any issues with racking while MLF is still ongoing? Or is it best to keep the wine as still as possible until the malolactic action has finished before racking?

 

[Turock]

No, don't rack while MLF is ongoing. Stir it gently a couple times a week to keep the MLB in contact with the wine.

 

[REDRUM]

Cool. Every time I stir there's a release of bubbles which had obviously trapped under the lees / gunk at the bottom of my demijohn... taking this as a sign that MLF is going OK!