In
vino veritas implies that a few drinks will enable us to be honest and the idea appears
to go back a long way in history. We humans have been enjoying alcoholic
beverages for at least eight millennia. That’s not to say we’ve been consistently
truthful for all that time, nor that truth is owned by the drinking classes.
Our
indulgence really comes not from our efforts, but from those of the yeast, Saccharomyces cerevisiae, whose little
cells work tirelessly on our behalf to turn that sugar water into wine; allowing
us to sip a really great wine and acknowledge the miracle. Magical as this may
appear, there is a deeper magic at play. The fruit are seasonal and fall, get
eaten or rot, but one way or another, disappear.
So
where does the hard working yeast go in the winter to re-appear, ready for work
at the correct time a year later? This was the concern of the large Italian-French
team of academics who have tracked down the answer and published their results
in this week’s Proceedings of the National Academy of Science (1). The answer
is that a significant proportion of the yeast is vacationing, sequestered from
the rigors of winter in the gut of social insects.
With honeybees, the
everyday worker insect has a regular turnover of its gut microflora through eating
and this goes on all year, albeit slower in the winter.
However, social wasps have queens, which feed themselves up to a nice degree of
plumpness in late summer and autumn and then hibernate to eventually re-emerge
and start a large colony the following year.
The
yeast cells overwinter in her gut, get spread throughout her new colony and
then distributed around the fruit for our eventual delectation and delight. DNA
analysis of gut contents indicated that this strategy had the additional
benefit of fostering relatively localized strains of the yeast.
This
brings out the warning that if we are careless about our local biodiversity we
will suffer in a loss of local character of our beverages.
- http://www.pnas.org/content/early/2012/07/26/1208362109.full.pdf
