PUNCH: Mysterious Mouse

[Richard Hastings]

All: 

Ran across this article on PUNCH recently and wondered what this group might think, especially regarding assertions about THP's resistance to SO2, and whether such occurrences may tend to self-correct given time. 

In addition, the author's comment on the potential for mouse to show up in response to disturbances is interesting:"This lines up with conversations I’ve had with winemakers from all over the wine world, in which mouse is viewed as a temporary phenomenon that is tied to moments of disturbance in the wine: racking, bottling..." 

And Brett, perhaps playing a role in helping resolve mousy flavors? Wow. 

For the record, I've been doing wild ferments for close to a decade now, and some of the above seems to correlate with that experience. Thus, perhaps, my fascination with what the article claims.

I've always addressed mouse as a "fixed flaw," i.e., if I taste it, I toss it...then puzzle over cause and/or blame. 

But is there more to the story? Should, as the author argues, we consider the possibility that mouse – at times, given all best-practice measures – be looked at as "...something the wine is going through – a journey, rather than a destination"? 

What says science? What says experience? 

Cheers, 

Rick Hastings 

[moo...@gmail.com]

Rick,

I've heard John McCarroll discuss this article briefly on the disgorgeous podcast and that it was somewhat controversial. Both he and Kevin are former cider reps in NYC, which they mention a lot on the show so it's worth a listen if you (like me) have been though every episode of every cider podcast you can find and have an interest in natural wine. 

Related to mouse, I believe it was on the Organic Wine podcast that Autumn and Ezra of Eve's discussed moussy cider that took care of itself and the magical disappearing mouse has also come up with several other cider / winemakers he's interviewed on that show (I believe it was mentioned on the episode with Todd Cavallo of Wild Arc Farm). I think another one of the ideas I've heard mentioned is that over-sulfited wines and ciders don't have their mouse problem resolve (maybe related to the absence of brett?). I have no experience, but it sounds like giving mouse time is kind of a working hypothesis amongst natural wine / cider makers and importers.

Matt

[Dave Mitchell]

THP is an interesting one.  I've found, to my detriment, that I'm very cognisant of it's existence.  Its also one I've rarely experienced in cider and natural wine.  In beer and kombucha it is another story.  I come across it in mixed fermented beers and kombucha more than I care to, with lambic and gueuze being an exception. 

It's been pretty clear that THP is related to oxygen and brett and LAB.  When I was at the MBAA conference in Calgary, I briefly talked to Richard Priess of Escarpments Labs about THP.  He confirmed what I suspected was happening.  Fermentation creates a precursor, then in the presence of oxygen it converts to THP, then in the presence of active microbes its gets reduced to a 'flavourless' compound.  This similar to diacetyl and is how I relate it to my colleagues.  It is a bit of a reductive explanation.  At time of the conversation, I believe there were a few variables that we're fully understood in the process.  I haven't really looked much into it since then.  Priess did hypothesis that micro-oxidation (as what you might see with aging in oak barrels) could prevent it being an issue.

Before confirming its formation, THP was a hurdle for me in homebrewing of mixed fermented beers.  I've greatly reduced the THP in my final beers by changing my bottling process by reducing oxygen contact.  It's not been a problem since.

I have found there is a certain point where THP will never disappear where years later it, to my palate, there has been no reduction.  It would be great to know if there any yeast/bacteria strains that are more effective at reducing it.

Do you know which Disgorgeous episode?  I found about the podcast last week but I haven't listened to any episodes.