MLF - How To Tell It's Going & 'Typical' Finish Times?

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we5inelgr

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Hi all,

A few questions about malolactic fermentation.

First, some details:
  1. Grapes involved - Cab Sauv, Petite Sirah, Pinot Noir, all fermented to 'dryness' (below 1.000 SG).
  2. Wine racked off lees.
  3. pH of all between 3.6 - 3.7.
  4. SO2 levels all around 5 ppm.
  5. Temp of juice ~72F.
  6. All inoculated (2 days ago) with MBR 41, along with ACTI-ML per instructions (except with ~110% recommended amounts).


Caveats:
I realize there is no 1 single answer that applies to each and every situation...just looking for some generalizations.
I know that there are tests, both expensive (easy w/quick results) and inexpensive (somewhat easy w/varying degrees of time needed). I plan to make that purchase next year. So for now, I'm not looking to have to purchase anything that would be required for testing MLF completeness.

With that in mind, I'm looking to get most ML converted based solely on (a) time and (b) visual clues (if any). For this year, I'm ok if I don't get 100% MLF completed.

I do happen to have some Lysozyme on hand so I can use that at the end (or perceived end) to arrest any ML bacteria that may remain.

The questions:
  1. How can one tell if MFL is occurring or has started?
  2. How long does it take to realize it is in fact occurring (& not stalled or stuck)? Ex. Should I know within a week?
  3. How long does a typical MFL take to complete for a red? Ex. Weeks? Months?

Thanks!
 
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Tiny bubbles is a sign that MLF is going. It could finish as fast as two weeks, or could be longer which depends
 
Without actually testing you'll be guessing. I started doing MLF's this year and did a lot of research. Tho I tested them all. Even when the test showed multiple batches progressing nicely, visually One would have noticeable activity while another had nothing to the eye.
For me I never paid any attention to airlock bubbling since the wine was still releasing CO2.
Having said all that
1. If there does happen to be visual activity they can be in the form of small bubbles rising. Speaking strictly from personal experience I would describe the bubbles as mini torpedos. They shoot up the carboy rather quickly. And it looks as if there's something solid attached to the bubble. It leaves a trail behind it in the wine as it shoots up the CarBoy. And when I look at the neck of the carboy all the way around I'll see a couple other torpedo lines left. They fade away in a minute or so. (I am only assuming these torpedo bubbles I describe are the MLF at work. But I can't say for 100% sure. Just describing my experience)
2. I'm positive there's absolutely no way to tell if it's progressing or sttalled without actually testing. Unless you're one of the lucky few who has an insanely sensitive palette.
3. There is no 'typical' for MLF. Too many variables that make each batch unique. I co-inoculated all mine so far and they finished very quick. First two were about three weeks. And my second 2 showed completion in 12 days. But co-inoculationhas been proven to have faster results. I also let it go another 2-4 weeks after test to be sure. The tests are not 100% conclusive.
Without testing I'd say your best bet would be to try your best to keep the temps up maybe mid 70°s. Stir the light lees into suspension maybe 1x-2x a week. Adding oak helps the bacteria- giving it something to latch onto and not get buried on the bottom. So adding some chips, cubes, or a spiral would help too.
And I think letting it go at least two months before racking and stabilizing would be a good idea. Long as your wine is topped up it will be fine without sulfites until then.
I highly recommend bucking up for the chromatography test kit You can eliminate so much guess work.
Good luck.
 
Thank you all for the reply's and suggestions.

Last night, I finally started seeing some activity in the form of very tiny bubbles on the surface. When I looked closer, I could see the tiny bubbles with the trailing "torpedo" bubbles @Ajmassa5983 talks about, but only in certain bottles and only on the sides.

One thing that became apparent to me after looking closer was that the wine I had in glass containers (1/2 and 1 gallon) were the only ones with the bubbles on the surface. The same wine in my 3 and 5 gallon Better Bottles did not. However, they have far more activity (visually anyway) around the indentations (on the sides) of the bottles with what sort of looks like the head of a Guinness beer after it's been poured, in terms of color and what the bubbles look like and behave like.

So it looks like I don't have to wonder whether MLF has started.

And yeah, I completely understand that testing is really the only way to determine if MLF has finished...and that "visual" chromatography or paper testing is only somewhat accurate at that. Because I've gone way over my budget for this first year vintage (building a cold box, buying initial supplies, equipment, etc) I plan to get the Vinmetrica SC-55 (newer version) sometime next year, as a reasonably accurate way to test for MLF completion.

For this year, now that I can visually see activity, I think I'll let it go until I see no more and then let it sit for another 2 weeks or so after which time I'll add some lysozyme to stop any ML bacteria that may remain.
 
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I don't know if anyone has mentioned this, so I will. I stir gently maybe twice a week, but if it is only once a week, don't worry. By gently, what I do is spritz my plastic spoon, insert upside down, give it one, two, three very gentle, very slow swirls through the wine, move on. I think it just keeps the MLB in suspension a little bit and helps it get done.
 
Thank you all for the reply's and suggestions.

Last night, I finally started seeing some activity in the form of very tiny bubbles on the surface. When I looked closer, I could see the tiny bubbles with the trailing "torpedo" bubbles @Ajmassa5983 talks about, but only in certain bottles and only on the sides.

One thing that became apparent to me after looking closer was that the wine I had in glass containers (1/2 and 1 gallon) were the only ones with the bubbles on the surface. The same wine in my 3 and 5 gallon Better Bottles did not. However, they have far more activity (visually anyway) around the indentations (on the sides) of the bottles with what sort of looks like the head of a Guinness beer after it's been poured, in terms of color and what the bubbles look like and behave like.

So it looks like I don't have to wonder whether MLF has started.

And yeah, I completely understand that testing is really the only way to determine if MLF has finished...and that "visual" chromatography or paper testing is only somewhat accurate at that. Because I've gone way over my budget for this first year vintage (building a cold box, buying initial supplies, equipment, etc) I plan to get the Vinmetrica SC-55 (newer version) sometime next year, as a reasonably accurate way to test for MLF completion.

For this year, now that I can visually see activity, I think I'll let it go until I see no more and then let it sit for another 2 weeks or so after which time I'll add some lysozyme to stop any ML bacteria that may remain.

Congrats on taking the plunge on MLF! Until you get test equipment, you can do what I do: taste the wine. MLF changes the taste from tart and fruity to buttery and smooth. It may take anywhere from a week to a few months.
 
Congrats on taking the plunge on MLF! Until you get test equipment, you can do what I do: taste the wine. MLF changes the taste from tart and fruity to buttery and smooth. It may take anywhere from a week to a few months.

Thanks for the suggestion and info Heather. I'm very much looking forward to tasting this wine throughout the process...and of course when its' done!
 
There is not much, if any, activity during MLF. Directions on MLF say to stir it to keep the bacteria in contact with the wine, but we no longer do this and the MLF finishes just fine. Remember--you have little or no SO2 on the wine and opening it up all the time can lead to oxidation risk. Accuvin has a kit for testing the malic in the wine, but I hate that test. It's not accurate. The best way to test for completion is chromotography test. Look at MoreWines catalog--they sell it.
 
There is not much, if any, activity during MLF. Directions on MLF say to stir it to keep the bacteria in contact with the wine, but we no longer do this and the MLF finishes just fine. Remember--you have little or no SO2 on the wine and opening it up all the time can lead to oxidation risk.

Good points to remember. Thanks!
 
Great thread, WE5INELGR!
I'm glad you started it....so I didn't have to! LOL

I am in the same boat.
I have made lots of wine from buckets and just recently decided to try MLF for the first time.
Like you, I have tiny bubbles now, so it appears to be active, but I do not have any way to test when it is done.
I may fork over the cash for an MLF chromatography at some point, but don't have one yet.

I guess for now, I will just have to taste test every week or two....no complaints here!
 
We are in our first MLF - 4 days in, stirring gently 2x per week, tiny bubbles. Today we will MLF readings today.
 

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