Feral vs Commercial yeasts

Clark,

I’ve repeatedly heard winemakers say the flavors difference yeast strains impart are inconsequential after a year [1], yet many go on to tout feral/wild/spontaneous/native fermentations. These are at odds. Why risk the ferment if the flavor differences are moot by the time they reach the consumer? Is this just Natural Wine marketing?

Also, thanks to your book’s excellent index, I see this topic was partially covered in a chapter I have yet to reach. Pg 115-116 says that by reducing the size of the inoculum, the resulting delay allows wild yeasts to do their thing an add complexity. I’d like to point out that while this may be true, underpitching the commercial strain would also add complexity. [2]

Thanks for making the time to participate here. I hope you will continue to be active on W-B beyond this week.

Rama

[1] http://www.wineberserkers.com/forum/viewtopic.php?f=4&t=92081&p=1312841#p1312841
[2] https://www.wyeastlab.com/com-pitch-rates.cfm (bottom paragraph)

Crickets. Even Clark Smith won’t touch this one?

Thanks for the Twitter heads-up, Robert. I wasn’t dodging your question, just didn’t realize I hadn’t gotten to it.

This is a pretty controversial topic. T seems some of us have had better luck with feral ferments than others. Joel Peterson and Gideon Beinstock insist that they consistently get complete fermentations with no off-aromas. That hasn’t been my experience. Obviously, when you spin the Microbial Wheel of Fortune, the results are very site-specific. Joel and Gideon are working from the same sites every year, with the capability of an integrated ecology that they’re happy with. So am I, but the sites I’m working with have produced more aggressive aromas and some sticking.

There is also the consideration of biogenic amine production and the carcinogen precursor urea, which I have discussed at length in another thread. I have sometimes employed the low-inoculum strategy you suggest with good results. If I use a low urea strain, it solves the second problem but not the first. I just have to decide if I want microbial complexity or grape flavor purity. It’s an artistic decision, with no pat answer and no right or wrong.

I have seen some discussion of sequential multi yeast inoculation, but have yet to speak with anyone who has tried it.

Do you have thoughts on this, of have you or anyone you trust done trials?