Wine

FRUITFUL WORK

B.C. scientists are raising the bar on wine research, writes SARAH EVERTS

August 30 2004
Wine

FRUITFUL WORK

B.C. scientists are raising the bar on wine research, writes SARAH EVERTS

August 30 2004

FRUITFUL WORK

Wine

B.C. scientists are raising the bar on wine research, writes SARAH EVERTS

TASTING THE FRUITS of laboratory labour is not a typical perk for most scientists. But when Steven Lund sips a delightful cabernet sauvignon, he is, in fact, doing research. Lund is an assistant professor at the University of British Columbia’s Wine Research Centre, and as he savours the ruby red liquid, he’s considering more than its integrated tannins, rich flavour and cassis nuances—or was that a hint of chocolate? Lund is also thinking about the grape’s genetics, wondering exactly which biochemicals signalled the fruit to begin ripening or which contributed to the wine’s bouquet.

Since being established in 1999, the wine centre has examined everything from how yeast ferments wine to which British Columbian soils produce the best grape varieties. In February, Lund and his collaborators received Canada’s biggest wine research award to date: $3.1 million from Genome Canada to sequence the fruit, seed and skin of the cabernet sauvignon grape.

This coup for the Vancouver-based research centre will help launch Canada into the forefront of wine science. Although researchers around the world have sequenced sections of other grape varieties, including chardonnay and pinot noir, no one has undertaken such an exhaustive genetic analysis of a single type of grape. “If we are

really going to advance grapevine genomics, we really need to focus on one single varietal,” says Lund.

Canada may be one of the youngest wineproducing countries in the world, but it takes wine research seriously. In addition to the UBC facility, there’s Brock University’s Cool Climate Oenology and Viticulture Institute in St. Catharines, in the heart of Ontario’s Niagara wine-growing region. “We have all the set-up to produce

OTHERS have

sequenced sections of a grape variety, but no one has tackled such an exhaustive analysis

the best wine in the world,” says Martin Godbout, Genome Canada’s president. “Why don’t we make it with the technology we have today—and the technology is the genomic technology.” Genome Canada, which Ottawa launched in 2000 to fund leading-edge genomics research, selected the UBC facility because of the university’s proven expertise in the field. The same team that sequenced the SARS virus in record time in April 2003 will help Lund

figure out the grape genetics behind a fantastic bottle of wine.

HUMANS HAVE tinkered with the grape for at least 6,000 years. Nowadays, wine researchers analyze the components of vineyard soil; monitor temperature, wind and rainfall using wireless gadgets; and experiment with irrigation and the planting of wildflowers as canopy for their grape vines. Even so, winemaking remains an educated guess. “I do things, all winemakers do things, whose answer can’t be found in a textbook,” says Bruce Nicholson, senior winemaker for Jackson-Triggs, a decade-old Canadian label that produces wine in both Niagara and B.C.’s Okanagan Valley. In fact, after 19 years in the industry, Nicholson says he’s convinced that winemaking is more art than science. “Ten or 12 years ago I would have said it is mostly a science, but I’ve realized that’s not the case,” he adds.

Genomics is aiming to change all that. Earlier this year, geneticists untangled a seemingly straightforward puzzle that had long eluded researchers—wine colour. It was well known that a grape skin pigment called anthocyanin is what tints red wine. But why isn’t it present in white grapes? All grapes— red and white—have two versions of a gene that directs anthocyanin’s production. In

A BRIEF HISTORY OF WINE ‘SCIENCE’

Genomics, it seems, is just man’s latest attempt to graft science on the noble grape. Some earlier approaches:

1750 BC

The Egyptians prescribe wine to purge the body of worms, regulate the flow of urine, treat asthma and act as an enema.

For these purposes, wine is mixed with kyphi, a combination of gums, resin, herbs and spices-not to mention the hair of asses, animal dung and bird droppings.

1000 BC

The Greeks, aware that lead kills bacteria, store wine in lead vessels to aid in preservation. Unfortunately, lead also kills humans. Resin, still found in retsina, is later added as a natural preservative. In Sparta, newborns are dipped in wine in the belief that if they go into convulsions as a result, they have epilepsy.

200 BC

Cato, a Roman politician, suggests flowers soaked in wine as a cure for snakebites, gout and constipation. Strong wine mixed with acidic pomegranates is taken for tapeworms and gripe.

33 AD

Roman soldiers reportedly give wine to Christ on the cross, to act as an anaesthetic.

May, Japanese scientists announced in the journal Science that in white grapes, both genes are mutated. Grapes with two normal genes are so dark they’re almost black. Red grapes split the difference, with one gene mutated, one normal. (Red wine enthusiasts take note: anthocyanin also helps grapes retain tannins—the bitter molecules that give red wine its charming astringency.)

For Lund and his colleagues, the focus is on the complex interplay of genes and the environment. First up: grape ripening. Small pea-size green grapes slowly grow to their full size over 12 to 14 weeks—and then suddenly transform into mature berries in a matter of days. It’s the grape’s equivalent of puberty, and the biochemical transformation can be just as complex. Lund estimates that about 10,000 genes are involved in ripening. As the newly mature grapes age on the vine, sugars accumulate, acids decline, flavour and aroma compounds are synthesized and red grapes acquire their pigment. Lund hopes that once viticulturalists have the genetic blueprint, they will be better able to detect, monitor and direct the onset of ripening before the grapes show it externally. “The whole point is to build not just a high-quality wine,” Lund explains, “but a consistent high-quality wine.”

MANY PEOPLE reel when GMOs (genetically modified organisms) are discussed in the same sentence as food or beverages. But Lund insists that the goal of his research is not to produce genetically engineered wine. If, for instance, Lund found genes in wild grape varieties that could improve flavour, or help grape vines withstand fungal infections or other pests, he would breed the plants traditionally. “If you used GMO

DARK AGES

Monks clarify red wines with egg whites and white wines with fish bladders. Clarification improves taste and shelf life.

MIDDLE

AGES

Cistercian monks in France introduce “cru,” a

system of classifying wine. An impressed Pope Alexander III exempts them from the tithe in 1171-and in 1180 threatens to excommunicate anyone who challenges the law.

1630

In Britain, the switch from woodto coal-fired ovens creates more durable glass-and stronger wine bottles. This,

along with the introduction of cork stoppers, improves wine’s shelf life. But bottle makers can’t produce consistent sizes, so in 1636 Parliament bans the selling of bottled wine: wine is bought in barrels and then stored in bottles.

LATE 1850S

Louis Pasteur determines that fermentation, the process that converts grape sugar to alcohol, is performed by yeast.

1991

The French Paradox: scientists wonder how the French can eat so much fatty food yet avoid heart disease. Red wine is credited and sales spike briefly. S.E.

technology you could speed it up 10 to 15 years potentially,” he says. “But if the consumer doesn’t want it we’re not going to go that route.” Still, researchers haven’t closed the door. “Inserting a grape gene into another grape plant is a lot different from putting a pig gene into a nut plant,” says Lund. “You can’t cross a pig and a nut plant, but you can cross grape vines. If genetic engineering becomes acceptable to the wine drinker, we’ll use the technology.”

So what exactly do wine drinkers want?

It’s a question winemakers are paying more attention to these days. There’s a 15-per-cent global oversupply ofvino, most of it in the bulk category. But market analysis shows drinkers want premium wines, with sophisticated bouquets and complex flavour. Here too, genetics research can play a part. Over 40 different molecules called terpenes are responsible for nuances of grapefruit, ginger, black pepper— and many more—found in wine. Terpene production is directed by grape genetics and is remarkably sensitive to the environment. The subtle difference, for instance, between diffuse sunlight and heavy shade on grapes alters the assembly of the various flavours.

Untangling this intertwining of sunlight and genetics is what Lund calls the more “simple” of his tasks. Knowing which hormones control terpene production might enable viticulturalists to encourage some bouquets but not others. Vintners are still “very much at the mercy of Mother Nature,” says Howard Soon, Caloña Vineyards’ master winemak-

er in Kelowna, B.C. “You can’t predict the hailstorm we had a few weeks back. Or the 40 degrees today.” With genetic knowledge, growers might be able to compensate when too much sun—or too little—threatens to alter the flavour of the grape.

On the horizon is the hard stuff, such as the genetics behind stressing a grapevine. Winemakers have known for centuries that clipping leaves and bunches off a vine or purposefully creating drought conditions produces smaller, more desirable berries with concentrated flavour. But so far, science has not been able to explain in any detail why the

VINTNERS are still

at the mercy of Mother Nature, but with genetic knowledge they might be able to compensate

practice works. Lund hopes to analyze which berry genes are turned on and off when the plant is stressed to determine which stressors have the most impact on flavour and aroma.

A little sun, a little stress—winemakers have long known these are important ingredients in producing a grape worthy of being bottled. And soon the science of grape genetics will help explain how such seeming intangibles work at the molecular level. For those who love wine, it could be the ultimate marriage of art and science. [i'll