adjusting TA prior to MLF

[GreginND]

That's true. Citric acid also produces diacetyl during MLF. The MLB strain also can impact the amount of diacetyl formation from malic acid.

 

[robie]

it depends on how much Malic is in the Wine, just because you go through MALO it does not ensure there is enough to produce diacetyl in levels that will be detected by our senses.

Very true. An MLF is not even needed unless there is excess malic acid to be converted.

 

[robie]

Interesting about the diacetyl in reds. I thought the majority of reds were put through MLF and only a few whites.

You gave me an idea though. I can order the exact same frozen must, and start MLF at a Brix of 5 for the second wine. Then compare the two finished wines.

What is nice about ordering frozen must is it lessons the risk of native yeast or bacteria begining fermentation. The supplier recommends not adding SO2 at all if MLF is going to be initiated. I added about 10 ppm anyway to be safe. To be perfectly honest, this is only my 3 batch of wine but I do read and research it as much as possible (without being fired from my real job)! It is slightly addicting!

Most of that pre-fermentation dose of SO2, if it is of the proper size) ends up being bound up (no longer considered free SO2) sometime before or during fermentation. If you did pre-dose properly, you should be OK to start MLF at the start of secondary.

I hope we are talking about fresh/frozen grape must and not kit wine must, as MLF should never be done on a kit wine.

 

[joea132]

I assume you mean press, instead of crush.
Yes, some wine makers press at different points in the process, based on factors such as the amount of tannins. If one pesses before fermentation is completed, certainly there will be a new buildup of CO2.

Yeah I meant press, sorry!

 

[spinelli01]

I hope we are talking about fresh/frozen grape must and not kit wine must, as MLF should never be done on a kit wine.[/QUOTE]

Yep. Definitely a frozen grapes and not a kit.

 

[wineman2013]

Very true. An MLF is not even needed unless there is excess malic acid to be converted.

I would disagree with this , all red wines (except kits) should go through mlf to ensure microbial stability and eliminate the risk of spontaneous mlf occurring in the bottle ruining the wine . This is a very common fault at amateur wine comps and just as an important reason for doing mlf as acid reduction and flavour improvement.

 

[wineman2013]

Many of the modern MLB strains are actually selected to produce low levels of diactyl as this is undesirable in red wines , mbr vp 41 is one example
http://www.lallemandwine.com/spip.php?rubrique33&id_mot=23&lang=en

Something to note if working with mega acid hybrid and American reds and whites , you can drop the acid sharpness without your norton or seval blanc tasting like cheese! (Using so2 at crush and cofermenting MLB and yeast also reduce diactyl production) http://www.lallemandwine.com/spip.php?rubrique4<=fr&td=1&univ=23

It's actually pretty easy to do mlf and produce almost no diactyl , so buttery flavours are a stylistic choice you can have or not have at your discretion.
http://www.lallemandwine.com/IMG/pdf_Sensory_MLB_2007_-_USA_ENG.pdf

Some good UC Davis mlf info
http://lfbisson.ucdavis.edu/PDF/VEN124 Section 4.pdf

 

[robie]

I would disagree with this , all red wines (except kits) should go through mlf to ensure microbial stability and eliminate the risk of spontaneous mlf occurring in the bottle ruining the wine . This is a very common fault at amateur wine comps and just as an important reason for doing mlf as acid reduction and flavour improvement.

I was not speaking specifically of reds. What I said is very true for a wine like a chardonnay. For Chardonnays, it depends on whether it is a clod climate .vs. hot climate grape. An MLF done correctly is never going to harm a wine, but it can be unnecessary. I say "done correctly is not going to harm..", because an MLF allowed to go too long or where the malic acid is very low to begin with and allowed to continue too long can harm the wine. The bacteria, if left too long, will start consuming and converting other than malic acid. The result can be considered a flaw at wine contests.

One should test and monitor and MLF, anyway so this would never become a problem.

 

[wineman2013]

My understanding is Mlf should always go to completion , so I'm not sure what you mean by go on too long . Do you have a reference I could read? I'd like to know more.

From what ive read Partial mlf wines are not made by arresting mlf but by blending an mlf wine with an un mlfd wine and stabilizing.

Co fermentations used to be avoided because of the risk of va production but modern strains and the latest Lallmand research , (linked above ) indicate that this risk is minimal , even non existant .

But the main reason for doing mlf on a Chardonnay isn't really an acid reduction thin , it's stylistic . White burgundy and Chablis are grown in the same climate , but one is wooded and mlfd and the other is clean and crisp . All other Chardonnays fall into one of these two styles.
Many warm climate California Chardonnays are mlfd , because some people like butter and wood .

Sometimes hybrid and American white grapes with really high acid levels are mlfd and a low diactyl producer is used and complete mlf is done and sometimes CS is also done to further drop acid but we are talking about grapes with acid levels over 11g/l and not vinifera.

 

[Inferno]

Thanks for the uc Davis and lallmand notes , excellent reading!

http://www.lallemandwine.com/spip.php?article743&lang=en

This one is very interesting.


Buttery aroma
Sequential inoculation with Beta, PN4 Eliminate as much as possible yeast lees Lower temperature during MLF
Quick stabilization with SO2 at end of MLF

Fruit driven-style
Co-inoculation with Beta, Alpha, VP41, new selection (upcoming)
Sequential with Lalvin 31, VP41, new selection (upcoming) Temperature during AF/MLF 18-20°C
Yeast lees contact
Delayed SO2 addition (minimum 1 week)

I would have thought leaving it on the lees and delaying so2 after mlf would have given you more butter not fruit . But lallmands research shows the opposite

 

[robie]

My understanding is Mlf should always go to completion , so I'm not sure what you mean by go on too long . Do you have a reference I could read? I'd like to know more.

From what I've read Partial mlf wines are not made by arresting mlf but by blending an mlf wine with an un mlfd wine and stabilizing.

Co fermentations used to be avoided because of the risk of va production but modern strains and the latest Lallmand research , (linked above ) indicate that this risk is minimal , even non existant .

But the main reason for doing mlf on a Chardonnay isn't really an acid reduction thin , it's stylistic . White burgundy and Chablis are grown in the same climate , but one is wooded and mlfd and the other is clean and crisp . All other Chardonnays fall into one of these two styles.
Many warm climate California Chardonnays are mlfd , because some people like butter and wood .

Sometimes hybrid and American white grapes with really high acid levels are mlfd and a low diactyl producer is used and complete mlf is done and sometimes CS is also done to further drop acid but we are talking about grapes with acid levels over 11g/l and not vinifera.

I am not trying to be argumentative with you on this, just trying to present the subject from my own angle. I do very much enjoy your posts and sincerely hope they will continue; we need your experience. Just keep in mind that the majority of our form members are not UC Davis students, graduates, or professional wine makers. They are newbies (and home wine makers, like me), just trying to gain a little more experience.

You wrote:
Many warm climate California Chardonnays are mlfd , because some people like butter and wood.

That is my point when I say MLF is not always necessary ("required"). In this case, it is NOT necessary to do an MLF in order to bring down the malic acid, since that acid level is likely already going to be low in a warm climate chardonnay. In this case, since malo is likely a very large part of the already low amount of available acid, by reducing it further with an MLF, the wine can ("can", not "will always") become flabby and lifeless, due to the now even lower acid. Tartartic acid likely will need to be added to taste. I didn't say there were not other benefits or stylistic reasons for MLF. Stabilizing with an MLF to avoid future MLF in the bottle is certainly something to consider. (Honestly, I think this is something that is happening to some of our members, as reflected by some of the recent threads.)

You wrote:
My understanding is Mlf should always go to completion , so I'm not sure what you mean by go on too long . Do you have a reference I could read? I'd like to know more.

I did not write that one should stop an MLF before it is completed. When MLF has converted the malic acid, the MLB should be killed/removed and not allowed to continue trying to consume/convert. One thing they will continue to convert is any residual sugar. If I remember correctly, citric acid is another, but don't quote me.

MLB are not always going to roll over and die just because there is no (more) malic acid to consume. If an MLF is allowed to continue past the point where the malic acid is extremely low or gone, the bacteria can and will start consuming and converting other substances. (I looked for the article from which I derived this fact but could not find it.)

I would say you should try an experiment for yourself. As in an environment where some wines are not given a stabilizing dose of added sulfites, do not rack or stabilize the wine after MLF is completed. Leave the MLB on the wine for, say, thee more months, again assuming the wine will survive not being sulfited. From the same batch, when MLF is completed, rack and remove the MLB (filter). Compare the resulting two wines to each other. Even Lallamand on page six of http://www.lallemandwine.us/pdf/article_state_of_art_ml.pdf says to filter the wine after MLF - Significantly reduce bacteria from the system to avoid potential quality degradation. . Of course this is partially because this will reduce the possibility of future MLF in the bottle.

I have enjoyed discussing this with you. If you want to continue this discussion, let's please take it off line to PM, as none of this is really beneficial to the original thread.

 

[Inferno]

In the lallmand article , not adding so2 right away produces a more fruit driven wine with less butter .
One of the substances the MLB eat after mlf appears to be diactyl , so maybe it can be a good thing , depending on what you want .

 

[robie]

In the lallmand article , not adding so2 right away produces a more fruit driven wine with less butter .
One of the substances the MLB eat after mlf appears to be diactyl , so maybe it can be a good thing , depending on what you want .

MLF produces diactyl. Alcohol fermentation reduces it.

 

[GreginND]

MLF produces diactyl. Alcohol fermentation reduces it.

Actually both form diacetyl and both can possibly reduce it. Here is an interesting paper looking at diacetyl concentrations with EC1118 and that showed at least one strain of MLF bacteria can reduce dacetyl.

http://www.ajevonline.org/content/46/4/442.abstract

 

[wineman2013]

http://www.lallemandwine.com/IMG/pdf_WUP_1_-_2012_Diacetyl_-_USA.pdf

In the article inferno originally posted , mt01 is listed as a strain the produces no diactyl and vp41 a strain that is used by many home winemakers because of its direct inoculation ability , tolerance of so2 and adverse conditions and speed of completion is listed as a very low producer.

So if you don't want butter you could pick one of these , let mlf compete , let the wine sit for a couple more weeks to let fine lees contact and the still active mlb with no more malic to eat to metabolise any minor diactyl residue , add your delayed so2 and not have any butter show at all .
Truth be told I've used beta on red wines for years in sequential inoculation , even with New York grapes with high TA , 9g/l plus and even though beta is listed as a high producer , I've never tasted butter in a red wine when using it. However when used on Chardonnay , yes you can taste butter , but in a Chardonnay I'm doing mlf on , it's exactly what I wanted.

The only red wines I've ever tasted with a notable diactyl flavour were American or hybrid grapes with acid levels over 13g/l that were inoculated post AF with a strong producer like beta. But many of these hybrids have kind of unusual flavours on their own , a little butter on that green fox didn't hurt any.

I guess the bottom line for me as a HOMEWINEMAKER is , if I don't want diactyl , I just order vp41 from more wine instead of beta .
How easy is that? They are even the same price
Vp41 has so many advantages its been my default strain for 4 years anyway , even before I knew it was a very low producer of diactyl .


And if you want a buttery Chardonnay , ferment with d47 (idealy in a new barrel , consider cubes) rack leaving as much lees behind as you can , into a carboy or tank when dry , add beta and optimalo . Let mlf go check its progress every two days with paper chromatography , as soon as its done gently rack it off the fine lees minimizing aeration , check the ph and get your so2 up where it should be ASAP.


Result!

 

[blazerpb]

Thank You Wineman 2013. Finally something I can understand.

 

[wineman2013]

Thank you I'm glad you found my public comments of benefit .

Steve

 

[altavino]

scott labs has some guidelines supporting winemans post , how to maximize and on the second page minimising butter

see here
http://www.scottlab.com/uploads/documents/technical-documents/913/Managing Diacetyl.pdf

 

[LoveTheWine]

Please correct me if I am wrong but the best time to check PH is at crushing (Or in your case with frozen juice just prior to pitching yeast) and after MLF. CO2 gas from the fermentation will throw off the pH reading. Even though you have pressed there still may be CO2 gas which can throw off your readings.

I agree with this. One way to get around that problem is to take your sample and shake it up for a while to get the Co2 out and then do your PH test.