there an art to wine science?
In this short article, I’m going to outline how
mainstream science usually works, and why it is so useful for
answering questions about the nature of the world around us. Then
I’ll discuss why, despite its utility, the scientific process is
of only limited real-world use for wine scientists, giving answers
to just a limited subset of important questions in viticulture and
winemaking. I argue that there’s somewhat of an art to good wine
science, even though this sounds dangerous and even heretical to
most trained scientists.
scientific method is an incredibly useful tool. It helps us
overcome our biases and prejudices, and allows us to answer
difficult questions. It helps us to be objective. It presents a
coherent model of the world around us that assists our
understanding of this environment, and enables us to develop new
technologies that actually work.
of the keys to the successful practice of science is objectivity.
People usually aren’t objective. We are pulled and pushed in
various directions by our inbuilt preconceptions, predilections
and prejudices. Good scientists will step aside and try, as much
as is possible, to be ruthlessly objective about the phenomena
they are studying. The two arms of scientific enquiry are
observation and experiment. Scientists look at what’s there,
formulate hypotheses, and then test those hypotheses by
experiment, trying their hardest to disprove them—this is the
only way they can be sure that they are correct.
scientific community is a remarkable global enterprise, uniting
researchers across the world by a common currency—data published
in peer-reviewed scientific journals (I’ll explain what I mean
by this below). It’s an inclusive club, open to all-comers, as
long as they have good data and are prepared to play by the rules.
gain credibility and status, researchers need to publish their
work in reputable peer-reviewed journals: their publication record
is how they are assessed. There are many thousands of these
journals, and they vary in their scope from broad to very narrow.
Not all journals are created equal: some have much higher
reputations than others. Typically, a scientist (or more commonly,
a group of researchers) will write up their results and then
choose the most appropriate journal to send them to.
will want to have them published in the highest-ranking journal
possible (there’s a sort of ‘pecking order’ of journals),
but they won’t want to send their paper to a journal where it
will be rejected, because of the delay in publication that will
ensue. How do journals decide which papers to accept? This is
where ‘peer review’ kicks in, a process vital to the integrity
of the scientific literature.
journal has a board of editors made up of leading researchers in
the field covered by the journal, and also a larger pool of
scientists willing to act as referees for papers in their chosen
subject areas. A paper coming in will be assessed by one of the
editors: if it is clearly unsuitable it will instantly be
rejected, but if it is potentially good enough, it will be sent
out to two or more scientists for review. They will prepare a
report on the paper, checking that it is correct, is suitable for
the journal it has been submitted to (if it is a high-ranking
journal, are the results exciting, novel and significant?), and
that the science is good. If they recommend it to be accepted,
they might also suggest possible revisions or further experiments.
Then the paper and the referees’ reports are sent back to the
editor, who makes a final decision whether to accept it, accept it
with revision, or reject it. Journals with good reputations are
more fussy than others. Getting your paper into one of the elite
band of leading journals can make your career.
all sounds great, doesn’t it? But if wine scientists restrict
themselves to the scientific method as detailed here, I’d argue
that they’d be of limited use to the wine industry. It’s my
contention that there is more than a little art involved in good
wine science. Let me explain why.
there has only been relatively little peer-reviewed research on
many of the most interesting topics in wine. This is because many
of the key issues for winegrowers are hard to address by good
scientific experiment, for reasons of tractability and cost.
It’s possible to do experiments in the winery, although this is
complicated by the fact that working with very small batches of
say half a ton at a time will introduce its own artefacts, and
microferments with even smaller quantities present further
technical challenges. Also, wineries are busy places at vintage
time, which makes experimentation difficult. In the vineyard
experiments are even more difficult, largely because to get
statistical power you’d need to have lots of randomized plots
which would then have to be managed differently. And add to this
the long time-scales involved in setting up a vineyard from
scratch, and it’s clear that the sorts of experiments needed to
answer some of the most interesting questions in viticulture are
pretty much impossible.
you could also ask the question about the usefulness and
reliability of the wine literature. Peer review itself is a
slightly controversial process because (1) it involves scientists
reviewing the work of their peers who may well be their
competitors, (2) it can take a long time, and (3) because some
consider it not to be as rigorous as it should be: good papers are
sometimes rejected while less good ones get through. To be frank,
it is not unusual for scientists to behave like assholes when they
are reviewing the work of others. Add to this the limits of
reductionistic science (breaking complex problems into little bits
and then observing these little bits in isolation has great
explanatory power, but it can only answer some sorts of
questions), and we end up with a body of peer-reviewed literature
that is only partly helpful—a jigsaw puzzle with half the pieces
is where I would argue that wine scientists need to blend in a bit
of art. They need to ski off piste. To be a good wine scientist
you need to make use of anecdotal evidence and the experience of
wine growers to fill in the gaps. To do this successfully is very
tricky: it involves making judgement calls, weighing up the
reliability and credibility of those you are speaking to, and
assigning confidence to extremely soft data points.
guess I need to explain here what I mean by ‘anecdotal’
evidence. Say over the course of a year you open a lot of bottles
and find perhaps a dozen that are suffering from musty taint. Or
you find that the grapes from one vineyard are considerably better
if you prune the vines short, or turn off irrigation just before
veraison. These observations may cause you to forge strongly held
opinions, but they aren’t data in the strict scientific sense.
Nor are they data when they are combined with the observations of
others whose judgments you trust. Even though the evidence may
seem to you to be unquestionable, what you have is an
not to say that anecdotal report is of no use—far from it. Data
collection is expensive and time consuming, and limited resources
don’t permit experiments on all the interesting aspects of wine
science. Instead, good scientists use hunches and anecdote to
decide where to look and which experiments offer the best chance
of success. And where we still lack data we have to use our
understanding of the science to fill in the gaps by educated
guesswork. This is a common theme in wine science.
course, this sort of approach horrifies many professional
scientists, because it goes against the way they have been trained
to work. It relies on the ‘art’ of the wine scientist in
holding on to what she or he believes to be useful or reliable
information, and rejecting less useful reports, often on the basis
of no more than a hunch. Yes, it has its perils. But I’d argue
that in the fields of viticulture and winemaking, to insist on
peer-reviewed research only puts us into a straight-jacket –
we’re like the drunk searching under the lamp post for his keys,
not because this is where he lost them, but because this is where
the light is. In an ideal world we should try to get solid
experimental data, but in the meantime, wine scientists need to
begin practising a bit of art, too. Some will do it well, some
will do it badly. That’s where the art comes in.