2018 Grape Season Underway

Winemaking Talk - Winemaking Forum

Help Support Winemaking Talk - Winemaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Paul that’s a damn healthy looking MLF. Good deal. I’ve got no actual logic to back this up- but it seems like co-inoculation in wine from grapes or juice with active skins seems to fair MUCH better for MLF. I think skins really help it along.
And I really don’t know what to make of this- but figure its worth pointing out. — I did a chroma test 10 days ago with only about 40% of wine showing activity yet all showed close to completion. Now 10 days later activity still very strong in the 40% plus the rest now too. And strong. Pop a bung and surface looks like tiny Mexican jumping beans popping out the surfaces. And I must admit I’ve only stirred up lees once early on. No plans to stabilize for at least another month.

Thanks, very pleased where everything is at this spring with wine.

I agree with your co-inoculation hypothesis. Skins make a difference on many levels it seems.

One of my carmenere/malbec carboys is doing that and the cab/syrah is. But just like AF there might be a period of degassing from MLF even though sometimes there seems to be no visible activity for some and yet MLF completes.

Not going to add any kmeta for a few weeks yet here either.

Now to decide what getting oak and how much and what kind.
 
I’ve got no actual logic to back this up- but it seems like co-inoculation in wine from grapes or juice with active skins seems to fair MUCH better for MLF. I think skins really help it along.

I can’t say that I’ve studied about th effects of the skins, and they certainly provide access to nutrients, and based upon what we know about the environmental factors that influence the MLB, the following coinoculation factors are favorable:

Low pH inhibits MLB - pH is generally increasing during AF and MLF - this is a positive
Low temps inhibit MLB - temps are generally rising during AF - this is a positive
High ABV inhibits MLB - ABV is near zero at inoculation, and increases over time, giving MLB a chance to establish and acclimate as the ABV increase - big positive compared to dumping them into a wine with ABV already in the teens
SO2 inhibits MLB - though yeasts produce it at different rates, like ABV, MLB establish in near zero environment and acclimate to the rising levels.

Just my two cents worth......
 
-
I can’t say that I’ve studied about th effects of the skins, and they certainly provide access to nutrients, and based upon what we know about the environmental factors that influence the MLB, the following coinoculation factors are favorable:

Low pH inhibits MLB - pH is generally increasing during AF and MLF - this is a positive
Low temps inhibit MLB - temps are generally rising during AF - this is a positive
High ABV inhibits MLB - ABV is near zero at inoculation, and increases over time, giving MLB a chance to establish and acclimate as the ABV increase - big positive compared to dumping them into a wine with ABV already in the teens
SO2 inhibits MLB - though yeasts produce it at different rates, like ABV, MLB establish in near zero environment and acclimate to the rising levels.

Just my two cents worth......

Understood. But the couple MLFs I’ve done with just a small amount of skins haven’t done as well as the full grape batches-with all other variables the same. I don’t know. Just seemed like grape skins help it out even more.
And it also seems like having a low abv enviroment helps all the other tolerances. And a 3.2 ph, low temp, or 35ppm So2 are much less an issue when inoculated early AF.
Using active yeast and mlb loaded skins in a 2nd ferment (I’ve done twice now) it’s pretty wild to see how fast both AF and MLF are able to finish too.
 
Last edited:
Using active yeast and mlb loaded skins in a 2nd ferment (I’ve done twice now) it’s pretty wild to see how fast both AF and MLF are able to finish too.

Everything is taking off running and hungry. AF usually takes about 3 days in this scenario.
 
-

Understood. But the couple MLFs I’ve done with just a small amount of skins haven’t done as well as the full grape batches-with all other variables the same. I don’t know. Just seemed like grape skins help it out even more.
And it also seems like having a low abv enviroment helps all the other tolerances. And a 3.2 ph, low temp, or 35ppm So2 are much less an issue when inoculated early AF.
Using active yeast and mlb loaded skins in a 2nd ferment (I’ve done twice now) it’s pretty wild to see how fast both AF and MLF are able to finish too.

I certainly didn’t mean to rule out the potential positive aspects of having skins present, just don’t know anything definitive about it, other than the fact that the skins and pulp have nutritional value.....and that’s a big plus too!
 
Just like native yeast grapes also have naturally occuring MLB although they seem to call it LAB.

https://winemakermag.com/665-the-biology-of-malolactic-bugs

Yessir. During my high ph/MLF/Lysozyme adventure last fall I had the joy of learning ALL about LAB and wine spoilage. Searching “LAB” produces more detailed results. so I assume it is the more accepted scientific term. But I’ll stick with MLB for sake of keeping simple.
Your post reminded me to share something I found a while back. Not tons of info on how bound So2 actually affects MLF but I came across a paper noting “liberated so2”. (I don’t know why but that term made me laugh). Then led me to google ‘corbonyl compounds’ followed by aldehydes and ketones then acetaldehyde and down the wormhole I went. Probably have forgotten 90% of it by now tho. IMG_1527977616.851493.jpg
https://www.extension.iastate.edu/wine/lactic-acid-bacteria-and-wine-spoilage
 
I certainly didn’t mean to rule out the potential positive aspects of having skins present, just don’t know anything definitive about it, other than the fact that the skins and pulp have nutritional value.....and that’s a big plus too!

As long as it wasn’t intentional I can let it slide....this time. :)
I wouldn’t expect anyone to fully agree tho because it’s literally NEVER mentioned. Before my 1st MLF I did lots of reading. More than a Dozen studies of sequential vs co-inoc. They all mentioned everything we already know regarding inhibitors. But another big difference aside from low abv - *I think- is the skins. And Overlooked by all those studies . I am not a professional scientist- I’m just a dude. But I’ll bet donuts to dollars that the presence of skins does a little somethin somethin for the mlb.
I’ve now done 7 separate MLF’s- all co-inoculated. And the only 2 that didn’t quite fully finish were juice buckets with a few handfuls of fresh grapes added- the rest were either full grapes or active skins to a juice pail. Just MY 2 cents worth.
 
The following was taken from a UC Davis paper. It seems that the skins are bringing in nutrients via the solids and old yeast that are in the process of autolysis.

The malolactic conversion is stimulated by autolysis of the
yeast. Extended skin contact and higher solids levels are also stimulatory to the lactic
acid bacteria. In contrast to the yeast, the bacteria require the presence of several
amino acids. That means that they cannot synthesize all 20 amino acids from
ammonia. Strains vary in which amino acids are required. Yeast release amino acids
at the end of fermentation, so amino acid limitation is not usually a problem unless the
bacteria are inoculated and the conversion expected before this release occurs. We
have found that the malolactic conversion occurs more readily pre-yeast fermentation
or after the release of the amino acids (post-fermentation), but is less likely to occur if
inoculated during the active phase of the alcoholic fermentation. Several proprietary
mixes of lactic acid nutrients are available, but if added early in the fermentation may
also stimulate yeast growth and metabolism. Again it is important to time nutrient
additions so that the desired population is the one that is fed.
 
The following was taken from a UC Davis paper. It seems that the skins are bringing in nutrients via the solids and old yeast that are in the process of autolysis.

The malolactic conversion is stimulated by autolysis of the
yeast. Extended skin contact and higher solids levels are also stimulatory to the lactic
acid bacteria. In contrast to the yeast, the bacteria require the presence of several
amino acids. That means that they cannot synthesize all 20 amino acids from
ammonia. Strains vary in which amino acids are required. Yeast release amino acids
at the end of fermentation, so amino acid limitation is not usually a problem unless the
bacteria are inoculated and the conversion expected before this release occurs. We
have found that the malolactic conversion occurs more readily pre-yeast fermentation
or after the release of the amino acids (post-fermentation), but is less likely to occur if
inoculated during the active phase of the alcoholic fermentation. Several proprietary
mixes of lactic acid nutrients are available, but if added early in the fermentation may
also stimulate yeast growth and metabolism. Again it is important to time nutrient
additions so that the desired population is the one that is fed.

Nice find.....hadn’t seen this one!
 
Racking the Pinotage today, hitting with kmeta and a med fr oak spirals.

The blueberry/malbec is at 11 months, opened a bottle yesterday and although pretty good, apparently in my haste to make room for last years fall harvest I didn't degas fully. Going to dumb in carboy today degas and bottle again in a day or two. No sediment in bottles.

Bottling pear/pineapple that is six months old. It is crystal clear and degassed.

Cab/syrah and carmenere/malbec batches I'm going to wait another 4 weeks before kmeta and oak.
 
Racking my Carmenere/PV this weekend. Chromo the other day showed MLF is done (probably has been for a bit, as I coinoculated). Got a fairly significant green pepper essence when I took a big sniff. That's a bit disappointing.
 
I have some hint of green pepper in my PV too. Does that fade?

Thx,
j

Carmenere tends towards "green pepper' from higher pyrazines more than petit verdot, but pv is a Bordeaux grape which I think overall are higher in pyrazines than other grape. It should fade and develop nicely with aging. I have a two year old carmenere that has developed nicely and any "green pepper" is gone now. Only one bottle left.
 
If excessive, there are various oak adjuncts or tannin products that can reduce the perception of green pepper. I guess it's a personal choice, some people argue that a little perception of pyrazines is a good thing, while others don't want any.
 
Racking my Carmenere/PV this weekend. Chromo the other day showed MLF is done (probably has been for a bit, as I coinoculated). Got a fairly significant green pepper essence when I took a big sniff. That's a bit disappointing.

Wouldn’t this be a perfect scenario where adding some oak to the primary would have been beneficial?
But then again- how do you predict when this would be more likely to happen without a crystal ball? Overripe grapes I know of. High pH/low acid maybe. Would brown stems/seeds be considered “overripe” and maybe cause green pepper (or any vegetal aspect)? And what else aside from overripeness?? (Just rhetorical questions. Not trying to derail the thread. Just how my ADD brain tends to work :)
It’s something a lot of us strive for I would assume. To be able to stray from your initial plans layed out- and call audibles based on on the grapes themselves. With so many other concerns on crush day it’s so damn difficult to cover all bases.
 

Latest posts

Back
Top