Malolactic Fermentation

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fossil112

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Hello,
I've read two different ideals when it comes to MLF.
One respected author states "adding the culture is always called for when acid levels in reds are high (TA>0.7) and two thirds of sugars have been consumed. If TA has been adjusted to ~0.5, you wouldn't need to add malolactic acid".
A second author doesn't clearly specify TA levels, but reference to begin MLF once primary fermentation is nearly complete, Brix=0.

I read the former author first, as my cab sauv TA=0.9 after crushing. So I began MLF at Brix = 7 (original Brix was 21.2).

My cab franc has a current TA=0.5 and Brix=10 (started 21.4). Haven't added MLF here -- debating whether or not I should.
 
Definitely would need to know your ph levels here. But when to add malo differs on who you ask. Meaning it can be done at many different times successfully.
Rule of thumb is mostly all red wines can benefit from MLF. Cab franc is definitely one of em.
Also, you can always just wait until after fermentation and racked off lees to check levels and then add your Malo if desired.
 
My understanding is malo works best once the sugars are consumed. The bacteria could degrade the sugar and create volatile acidity.
 
I post innoculated and co-innoculated mlf in different batches this year, both completed and smell good, the co-innoculation finished quite a bit faster. But i made my co or post innoculation decisions based on ph/ta of the must before fermentation, if the ph/ta matched the parameters for mlf i co-innoculated, if they ph/ta were outside mlf parameters i fermented and tryed adjusting using malic metabolizing yeasts to slightly adjust into the good mlf zone. Right now im dealing with two batches that are very low ph and high acid so im adjusting, fermenting, then most likely tweak again after fermentation before pitching mlf, this chart might help.

6EF333EB-93B5-4EA2-8FE5-2026194FA87E.png
 
Yea that was the theory before. Buts it's actually been proven to work just as well with sugar present. There's a ton of discussions about it on this forum. Here is the most recent thread:

MLF - coinocculation versus post-AF innoculation
http://www.winemakingtalk.com/forum/showthread.php?t=57673

But so you know ph is the level mostly concerned with MLF. Namely a low pH. Because most strains of malo bacteria only will work above ~3.2 range. If your gettin into MLF's then a cheap ph meter (not the test strips) would hugely be of benefit.
With a TA of .50 you likely will be much higher than 3.2 ph so no worries about MLF not starting. I've learned when incoculating malo during AF it's important to properly feed the appropriate nutrients to the yeast as well as the MLb.
 
I just ordered a digital pH reader from amazon yesterday, so should be here on Tuesday.
What I don't understand is why I need to add tartaric acid to get my franc to 0.5, only to begin MLF which will consume it. I'm missing something here.
 
I post innoculated and co-innoculated mlf in different batches this year, both completed and smell good, the co-innoculation finished quite a bit faster. But i made my co or post innoculation decisions based on ph/ta of the must before fermentation, if the ph/ta matched the parameters for mlf i co-innoculated, if they ph/ta were outside mlf parameters i fermented and tryed adjusting using malic metabolizing yeasts to slightly adjust into the good mlf zone. Right now im dealing with two batches that are very low ph and high acid so im adjusting, fermenting, then most likely tweak again after fermentation before pitching mlf, this chart might help.

I love Scott Labs. Thanks for the diagram!
 
I just ordered a digital pH reader from amazon yesterday, so should be here on Tuesday.
What I don't understand is why I need to add tartaric acid to get my franc to 0.5, only to begin MLF which will consume it. I'm missing something here.

Malolactic bacteria converts malic acid to lactic acid, not tartaric acid.
 
Keep in mind that MLF is the process of lactic acid bacteria (oenococcus oeni) converting malic acid bacteria into lactic acid, co2, and some other goodies like diacetyl. The tartaric acid you dump in before MLF will remain after MLF. You dump in malic acid however, and it will get converted to lactic. You definitely don't need to add tartaric or any acid for that matter to get your TA to 0.5g/100ml.
 
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You definitely don't need to add tartaric or any acid for that matter to get your TA to 0.5g/100ml.

Agreed, i wouldnt adjust my ta before mlf for the sake of adjusting ta, i would use tartaric acid or pottasium bicarbonate to adjust my ph into a better position for mlf before pitching if i needed to correct it. Your ph is much more important than your ta. Ph will determine whether or not your mlf will complete or even start, ta is a matter of taste.
 
Agreed, i wouldnt adjust my ta before mlf for the sake of adjusting ta, i would use tartaric acid or pottasium bicarbonate to adjust my ph into a better position for mlf before pitching if i needed to correct it. Your ph is much more important than your ta. Ph will determine whether or not your mlf will complete or even start, ta is a matter of taste.

that's what I'm looking for. I haven't read how the two differ in terms of affecting final product.
Will know pH middle of next week, which should be fine because i'm nearing the end of primary fermentation. At that point, I can adjust pH as necessary.
I also have another bottle of bacteria in the fridge if need be for anything.
 
Good luck. Take as much in as possible. Every single aspect is a never ending pool of knowledge that is never full. From MLF, adding/removing acids, yeast/malo nutrients, and how they all co-exist and affect each other. And when unsure---keep asking questions here like you've done.

Ph meter newbie tip: don't do what I did and ruin your meter from lack of proper use/care knowledge. Hopefully you got liquid buffer solutions 4.01 and 7.01 to calibrate. These are necessary. Also be sure to always store your meter in buffer solution 4.01 or actual ph meter storage solution. If it dries out it can easily get all jacked up.
The 1st one I bought was off Amazon for maybe $15. It calibrated with 4.01 and 6.86 NOT 7.01. (an odd buffer ph. Difficult to find.). Plus they weren't liquid they were granulated packets. Just a big ol hassle.

Ph meter use and care
http://morewinemaking.com/public/pdf/wphmeter.pdf

MLF pdf
http://morewinemaking.com/public/pdf/mlf09.pdf

My winemaking bible- covers pretty much everything. And I refer to this often.
http://morewinemaking.com/public/pdf/wredw.pdf

These are all from Morewine.com. Whoever put these manuals together did a fantastic job. They really wrote in a way that doesn't just tell you what to do, but also why. And explains everything in a way with logic and reason giving examples throughout for clarity.
 
My fault on that - I added an acid blend that contains both malic and tartaric.

The malic portion of that acid blend may very well remain in your wine since some forms of commercial made malic acid will not be metabolized by MLB (I believe I learned that from @ibglowin , a man much smarter than I).
 
If you have a hydroponic shop in the area they will have all sorts of ph meters and the liquid calibration solutions and the storage solutions, paid about $5 each for each solution
 
The malic portion of that acid blend may very well remain in your wine since some forms of commercial made malic acid will not be metabolized by MLB (I believe I learned that from @ibglowin , a man much smarter than I).



But I imagine some of it could be metabolized. So if all you have is acid blend, perhaps better to add before MLB. Might make it difficult to read the chromotography.
 
But I imagine some of it could be metabolized. So if all you have is acid blend, perhaps better to add before MLB. Might make it difficult to read the chromotography.


I had read somewhere, and I should have made a note of that place, if it was reputable or not. Man-made malic acid and that's what is in acid blend cannot be metabolized by MLB. Also, I would worry about the citric acid in acid blend and MLB, doesn't it get metabolized into acetic acid?
 

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