MLF - coinocculation versus post-AF innoculation

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fafrd

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Upon thevadvise of my local wineshop, I coinnoculated last year (MLF innoculation 24h after pitching yeast) and everything worked out well.

Gearing up for this season, I've been doing more research on MLF and it seems most references recommend innoculating at the end of alcoholic fermentation (0 BRIX) or even after racking off of the gross lees (24-48 hours after pressing).

From what I've read, the primary reason to avoid coinnoculation is fear of VA (bacteria consuming sugar).

I'm curious whether most home winemakers are coinnculating or innoculating at 0 BRIX or post-press.

For those who co-innoculate, has anyone ever had an issue with VA?
 
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My preference is to conduct MLF concurrently with AF, it typically continues on for several weeks past the completion of AF. Have not ever encountered any problems doing it this way.
 
I noticed more adding ML after primary than during. Benefitting from not having any gross lees with the ML.
I have only 2 MLf's under my belt, and circumstances forced me to coinnoculate. With some guidance from Johnd I added ML after yeast kicked off and directly with yeast in 2nd batch (via skins).
I noticed many other member's batches with same grapes took much longer to complete. But both of my mlf's finished <30 days. - I assume the low alcohol at 1st helped. Faster might not be better- but it worked well and I plan to continue.
 
I, personally, haven't done it.
When I first started making wine from grapes I saw some posts explaining that the yeast and the malo culture could be fighting for nutrients and such and it was advisable to innoculate the malo once AF is depleted or almost done (typically 1.000 is a good point).

I may try co-innoculating a small batch in a near future to see how it goes though.
 
I, personally, haven't done it.
When I first started making wine from grapes I saw some posts explaining that the yeast and the malo culture could be fighting for nutrients and such and it was advisable to innoculate the malo once AF is depleted or almost done (typically 1.000 is a good point).

I may try co-innoculating a small batch in a near future to see how it goes though.



Good point. Either method seems to have both pros and cons. But I liked how I was able to just bang it all out at once. I'm thinking properly using Acti-ML, opti-malo, fermaid k etc... helped counter the battle for nutrients.
Also, if it does in fact help MLF finish faster, then another benefit is the ability to get some so2 in there sooner for protection. I tested completion just under 30 days but let it go further and finally stabilized after 8 weeks. Much more comforting than 3 or 4 moths.
 
I noticed more adding ML after primary than during. Benefitting from not having any gross lees with the ML.
I have only 2 MLf's under my belt, and circumstances forced me to coinnoculate. With some guidance from Johnd I added ML after yeast kicked off and directly with yeast in 2nd batch (via skins).
I noticed many other member's batches with same grapes took much longer to complete. But both of my mlf's finished <30 days. - I assume the low alcohol at 1st helped. Faster might not be better- but it worked well and I plan to continue.

You mean you noticed more VA when innoculating at the end of AF?

The only downside I've been able to identify against co-innoculation is the potential for VA - if that's not a problem any of us home winemakers typically run into, it's much easier process-wise to co-innoculate.

Anyone actually tried co-innoculation and regretted it due to VA production?
 
I, personally, haven't done it.
When I first started making wine from grapes I saw some posts explaining that the yeast and the malo culture could be fighting for nutrients and such and it was advisable to innoculate the malo once AF is depleted or almost done (typically 1.000 is a good point).

I may try co-innoculating a small batch in a near future to see how it goes though.

That's the conventional wisdom...

So you innoculate into primary at 1.000 before you press? Do you rack off of gross lees?
 
I co-inoculate typically and have not had issues.

Here's a link to a Scott Labs document that goes into more detail:
http://www.scottlab.com/uploads/documents/downloads/318/ML Brochure.pdf

Thanks for that link - I'd not seen that before.

The primary benefit of co-innoculation is to get the bacteria well-established while the environment is especially inviting (low alcohol). So MLF is supposed to finish much more quickly and reliably.

The benefits of post-press innoculation are avoidibg any possibility of VA (no more sugar) and only introducibg MLF bacteria once off of gross lees.

But getting MLF started in alcoholic wine is tougher (though that is how the bacteria has been doing it for centuries within oak barrels ;)).
 
I have co-innoculated my last two batches in the spring. Didn't have VA problem but with my Malbec MLF never kicked off due to low pH. Got it to kick off eventually with k-bicarb adjustment and re-innoculation. With my S Afr Cab Sauv MLF completed nicely.
 
I do about 45 different lots of red each year and have had all kinds of MLF results using CH16 bacteria and various yeasts. I've always added bacteria after primary and sometimes it takes off really well and is finished in a week or two. Sometimes it takes two months. Sometimes it never takes off and I have to heat up the barrels and reinoculate. At the end of the day the results have always been fine, although there's always better barrels than others. Hard to pin it on MLF though.

This year I am going to do a lot of 1/2 regular (post-primary) bacteria inoculation, and 1/2 co-fermentation. I'm hoping I can get quicker, smoother MLFs out of the co-fermentations. I'm in the process of checking my yeasts for compatibility. I'll be sure to post the results later in the season.
 
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I do about 45 different lots of red each year and have had all kinds of MLF results using CH16 bacteria and various yeasts. I've always added bacteria after primary and sometimes it takes off really well and is finished in a week or two. Sometimes it takes two months. Sometimes it never takes off and I have to heat up the barrels and reinoculate. At the end of the day the results have always been fine, although there's always better barrels than others. Hard to pin it on MLF though.

This year I am going to do a lot of 1/2 regular (post-primary) bacteria inoculation, and 1/2 co-fermentation. I'm hoping I can get quicker, smoother MLFs out of the co-fermentations. I'm in the process of checking my yeasts for compatibility. I'll be sure to post the results later in the season.

Lloking forward to your results!
 
At 1.000 or so, I press. Then I wait 24~48 hours and then I rack and finally MLB goes.

'Goes' as in starts (takes-off)?

'Goes' as in 'goes in' (meaning you innoculate after racking off of gross lees)?
 
This is just my hunch, but I think having some sugar left in there when inoculating with MLF would be beneficial to get the bacteria population growing well. And the heat from AF would help the bacteria. I have inoculated at about 2/3 sugar depletion of AF and have had good results, but I don't have enough data points to know for sure what the trends are. I will probably try inoculation one or two days after yeast addition this year. My guess is that it really doesn't matter when you add the MLB as long as you have enough nutrients for all.
 
I have read (but not confirmed independently) that co-inoculation results in slight loss of color and complexity compared to sequential.
 
I have read (but not confirmed independently) that co-inoculation results in slight loss of color and complexity compared to sequential.



I did a lot of reading up on this topic leading up to my first MLF in spring. I will look for these articles and share if I find them.
From the researching I learned:

The accepted standard is inoculating ML after racked off gross lees. Doing it this way is would get the most and best out of what the MLF has to give- from a factual scientific standpoint (I remember the reasoning was multiple items and very detailed on all points) BUT can also not be the most ideal method for home winemakers.
From a logic and reason standpoint co-inoculating is growing more popular. Given a home winemakers limited lab and means, it's a matter of risk and choosing the lesser of two evils.
-adding ML after AF and getting the most out of it, but with a higher risk of not starting/stalling/ or taking a very long time.
-adding during AF giving MLF a higher probability of starting/finishing/ and potentially in a much shorter amount of time. But risk having results that could potentially be 'less than' that of adding malo 'after AF'.

Personally I read that not as "negative" results, but more like "less positive" if that makes any sense. Like donating $100 to charity vs donating $75. Both ways still affect your wine for the better.
I really have no clue how noticeable the difference would be without a controlled taste test. But I figured it would be minimal and maybe not even noticeable to some. I will continue to co-inoculate simply because it worked so well for me.
What is really needed is for someone to divide a batch right from the jump so they can inoculate both ways and logging all the progress and final tasting. But that's a hella amount of extra work for something I believe would be minimal differences.

---I just reread my post and realized I gave no info at all for any of the reasoning. I need to dig that article up.
 
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