MLF Fermentation Duration

[Jenks829]

Ladies and gents, everyone has been very helpful to me ever since I started posting here. I've greatly appreciated all the advice I've received and hope that I can one day bring something to the table. I come to you wise winemakers and ask your advice once again. This time with the fickle topic of malo-lactic bacteria.

I inoculated with MLB around 11-23-10. For about 3 to 4 weeks after inoculation, I had a space heater on in the same room as the carboys. The temps on the stick on thermometers on the carboys was reading 70/72F. After a month I turned the space heater off. I performed a malo-lactic chromatography test kit 3 days ago and the results showed that we still have malactic acid present. I was really hoping that the wine could have finished MLF by now and I could take advantage of the cold weather and un-insulated garage to cold stabilize. More importantly, now that I know that the MLF is not done, I am worried about avoiding involuntary MLF later on.

What are everyone's thoughts on this? Should I add some MLB food/energizer? Maybe raise the temp and swirl the carboys to kick the bacteria out of the sediment? Or simply wait it out?

Thanks guys/gals. As always, your advice will be greatly appreciated.

 

[JohnT]

Need more info..

Do you know that MLF has begun at all? Did you do a baseline chromtography test prior to pitching your culture?

Also, did you test the level of SO2? MLB is very delecate when it comes to k-meta. You should have a level of about 20ppm or lower for MLF.

 

[Tom]

Whats the Temp?
What does the manufacture of the MLB say for the temp range?
with the info you have I say raise the temp.

 

[grapeman]

Also what was the pH and TA of the wine before innoculation. Some of them are more sensitive to acidity levels also (pH). With the extra information we can make an educated guess for you, but without these things, it can be a crapshoot.

 

[Jenks829]

Do you know that MLF has begun at all? Did you do a baseline chromtography test prior to pitching your culture?

Also, did you test the level of SO2? MLB is very delecate when it comes to k-meta. You should have a level of about 20ppm or lower for MLF.

John, I did not perform a baseline chromatography test prior to pitching the MLB. I believed that MLF had at least begun because of the small bubbles that appeared around the neck of the carboy. I also believe that MLF is at least going the right direction because the chromatography test showed the presence of lactic acid and no evidence of citric acid.

The SO2 level was 30ppm when we crushed the grapes. We've added no additional potassium metabisulfite since then. At the same time I performed the chromatography test, I took a SO2 reading with a Titrets test kit, I never noticed a change to colorless in the test tube. It is my belief that I have no free SO2 in the wine (which worries me) or at least not enough to be measured.

Whats the Temp?
What does the manufacture of the MLB say for the temp range?
with the info you have I say raise the temp.

Tom, the temp of the wine right now is 60/62F. I do not know the what the manufacture recommended temp range is. I did have a space heater on the carboys when I first inoculated with MLB in an effort to get the wine over 70F to ensure MLF had a good shot at getting started. I kept the heater in the room for about a month. During that time, the wine was always over 68F. I am at work now so I will have to wait until I get home to consult my notes and see which MLB I used and research the temp recommendations.

Also what was the pH and TA of the wine before innoculation. Some of them are more sensitive to acidity levels also (pH). With the extra information we can make an educated guess for you, but without these things, it can be a crapshoot.

Grapeman, we have two batches going: 330 lbs of Merlot grapes and 324 lbs of Cabernet grapes. Both finished at 0.996/0.997 final gravity. pH was 3.3/3.4 for the Merlot and 3.4/3.5 for the Cabernet. TA was on the high side at 0.9% and 1.0% respectfully. It was my understanding that these pH levels were acceptable. I did not consider the TA level. Do these levels sound too high?

I appreciate everyone's input

 

[pkeeler]

pH was 3.3/3.4 for the Merlot and 3.4/3.5 for the Cabernet. TA was on the high side at 0.9% and 1.0% respectfully. It was my understanding that these pH levels were acceptable. I did not consider the TA level. Do these levels sound too high?

Will cold stabilization kill the MLB? I wouldn't think so, might make them dormant. I'm a newbie at wine, but why couldn't you cold stabilize the wine to lower those TA numbers. Then bring the wine back up to MLF temp. and see if it starts again? Your pH numbers look good but the TA numbers are high. How does it taste?

 

[Jenks829]

Will cold stabilization kill the MLB? I wouldn't think so, might make them dormant. I'm a newbie at wine, but why couldn't you cold stabilize the wine to lower those TA numbers. Then bring the wine back up to MLF temp. and see if it starts again? Your pH numbers look good but the TA numbers are high. How does it taste?

I am a newbie at wine also. When grapeman mentioned the TA levels, I was thinking the same as you. Could I CS to reduce the TA and then restart MLF in the spring time. My only concern would be the wine being unprotected by SO2 levels for that long of a time. Even if the low temps did kill the MLB, I would have no issue with re inoculating after the CS.

I did taste some. I don't know how to describe it accurately. Half because I've never tasted in process wine and half because I had 3 or 4 beers before hand. The good news is, it did resemble wine. It had a lot of body and mouth feel to it. I don't know how to detect the softness of the lactic acid.

 

[Jenks829]

So I spoke with the "wine guy" at my LHBS and he advised me to let MLF continue for another week or so and then run a chromatography test again and if I wanted to cold stabilize at that point, I should still have about 4 weeks of cold weather to get that done. In the spring time he said the mlf will pick back up or I could add potassium metabisulfite and Lysozyme to prevent MLF from continuing. Then I could oak, bulk age and bottle.

Right now I am leaning towards CS in about a week and then adding some MLB nutrient to finish MLF in the spring. This is just my beginning thought. I have very low sulfite levels now and I don't want to risk spoilage so I may be talked into the Lysozyme at a later date.