Riddle Me This, Batman....................

OK, I have a bit of a mystery on my hands. Any sleuthes out there?

Our '08’s are super high in alcohol, and due to this (or so I thought), I have several small lots of wine with stuck ML’s. We have a warm room, so temperature was not an issue. I reinoculated in January, with not much luck (or so I thought). When checking ML’s, I would just take composite samples- trying to take the same amount of wine out of each bbl to check the numbers (via spec). Well, it looked as if everything had stalled, and we were starting to get some VA and stuff, so we just decided to throw in the towel, rack these lots, and put them to bed. Well, we have racked 6 lots since Friday, keeping the new and neutral barrels separate, and I have got some very interesting results. In all of the lots I have checked, now that they are racked together in tank, ALL of the new barrels are actually through ML, and none of the neutral bbls are done. WTF? Up until this point, we were using hot water then ozone to wash our barrels (we just got a steam generator last week), so our barrels should be clean. Was there something horribly inhibiting left over in the neutral barrels? Could there be such high levels of something left over to be that inhibiting? The FSO2’s were all next to nothing, so I can’t imagine that would be a problem. I was wondering if maybe the wine was taking up SO2 from the gassing of the barrel, so Friday I filled a gassed bbl with water and checked it Monday- it was 2.5ppm. I will check it again at other intervals. I am at a loss.
Any ideas?

If things don’t work out, I recommend making a really nice, full bodied Rose out of it.

Funny thing about ML. Never thinks of completing until you throw in the towel and hit it with SO2. I would assume that you killed off whatever was competing with the ML. What was the Alc and the ml strain that was used each time? did you use leuco food?

Same problems with two different Zins, both fairly high alcohol. I decided to rack one lot out of barrels, add more Acti ML and try a different ML strain. Voila - the wine is done ML in a week.
I thought it was the alcohol but I had other lots of similar alcohol levels sail though with the original strain we were using. I have given up trying to understand.

-Bryan

Initially used VP41 one-step which comes with nutrient. Second time used CHR Hansen CH16 with a Lallemand nutrient (don’t tell Lars I mixed his bacteria with a Lallemand product ), prior to reinoc I used yeast hulls to try to clean things up. The alcohols ranged from 15.7-17.4 (!!), with most in the low 16’s. It’s really the new/neutral thing that has me scratching my head.

Sometimes racking will get rid of whatever inhibiting factor is in the wine. Yeast hulls can do this as well.

Were the new and used barrels possibly segregated during the innoculation and been subjected to different innoculation protocols?

Aside from the negligible impact of SO2 from the old barrels, the only difference should have been the presence of some pentose sugars in the new barrels, but I can’t imagine that having any impact?

They were inoculated while still in tank.

I would like to blame it on the winery gnome, but ours has a busted leg and probably can’t climb barrel racks right now.

Maybe the tank innoculation failed and the new barrels had an ambient/ubiquitous population of bacteria that was diverse enough for something to kick? Whereas the clean old barrels would have been sterile.

Here’s a thought. If you had higher than expected EtOH’s, that could be a lot of things, but one option is a lower proportion of nonfermentable sugars. If that’s the case, perhaps there’s enough 5 and 6 carbon unfermentable sugars that are produced in the toasting process that may sustain or kick off the ml cultures. Not sure about ML strains and their efficiency of metabolizing various 5 and 6 carbon sugars though. Hmmm.

Lars would not approve. Im thinking Ch 16 could pretty much get port through ML. Did those wines go dry? If so good work!

All were dry except the 17.4% wine- it’s at about 0.4% sugar.
Lars is coming to Peachy today. Don’t rat me out.

Linda,

ML fermentation as well as primary fermentation always goes better in new wood rather than older wood. I think that new wood has more micronutrients available rather than anything to do with the sugars.

You can use this to your advantage by racking the lot up and back when the new oak is boiling through.
Greg

That’s interesting, Greg. I’ve never noticed primaries going faster in new wood. We do native on chards that typically last until May or June of the year following, and I’ve never seen new wood finish first. I wonder if that is vintage dependent, site specific of something else.

Higher oxygen transfer rate of the new wood makes things easy. How old is the old…? No stirring?

Oldest is about 2003. Some stirring, every 2-3 weeks. Not sure about the oxygen- Oenococcus is microaerophilic, so it seems like normal oxygen transfer through a barrel would be sufficient. I was checking them pretty much weekly, so I was opening the barrels on a regular basis.
I like Greg’s and Jeff’s ideas about the new barrel micronutrients and sugars. I was thinking more in terms of something in the neutral barrels which could have been inhibiting, but the new barrel promotion of ML factor could be it.

Thanks for playing along, guys. I will now mull over what will be the prizes for the best answers.

Hi Linda,

I would agree with Peter’s first assessment. I have found that with “challenged” ML ferments, the residual SO2 in older barrels (both from SO2 in the previous use wine and empty barrel maintenance) is enough to block MLs…

Cheers, Even