"pp" > wrote in message
om...
> "Lum" > wrote in message news:<uutAc.480> >
> > > Ar a recent talk, a professional winemaker here from BC mentioned that
> > > they were getting higher alcohol levels for the starting Brix than
> > > they used to, often by 1% or even more. She said this was confirmed by
> > > other winemakers from the area. Her hypothesis was that the yeast were
> > > getting more efficient in alcohol production. This could have large
> > > repercussions if that were indeed the case. I'm wondering if this is
> > > happening in other, hotter areas, as well?
> > >
> > > Pp
> > > Vancouver, Canada
> >
> > Some types of wine yeast produce more alcohol than others, so the above
> > situation certainly seems possible. But, I don't understand what the
"large
> > repercussions" would be.
> > Lum
> > Del Mar, California, USA
>
> Well, if the yeast got consistenly more efficient in producing
> alcohol, then the winemaking practice would have to adjust to that
> somehow, particularly in hot areas, otherwise we'd end up with hot,
> unbalanced wines, no? 1% is a lot as an average change.

Going from 12 to 13 percent alcohol would indeed change the general
character of many wines, but making well balanced, high alcohol wines is not
necessarily difficult. Going from 13.1 to 14.1 percent alcohol results in a
big change in the tax due on commercial wine made in the USA. Of course,
the winemaker can control the alcohol content of the finished wine to some
extent by adjusting the starting Brix (one way or another).

> I believe she's been using the same yeast over the years, so it's not
> a change in the type of yeast.

If she has been propagating her own yeast for many years, I would suspect
the yeast has changed. On the other hand, if she is using dry yeast, then I
suspect the additional alcohol is due to some factor other than yeast.

Regards,
Lum
Del Mar, California, USA