Terroir on a 100-Point Scale

Can great vineyards be measured? This Italian thinks so

<i>Terroir</i> on a 100-Point Scale
To understand differences between sites, agronomist Giovanni Bigot examines factors such as how vigorously each vine grows, how much fruit it produces, how many leaves it has and how healthy the grapes are. (Robert Camuto)
Apr 9, 2021

Giovanni Bigot may be on to something.

This 48-year-old agronomist and researcher from northeastern Italy’s Friuli region has developed an intriguing 100-point scale for measuring the potential of vineyards to produce great and unique wines.

In other words, he’s scoring terroir—overlaid with vineyard practices and the overall health of the grapes.

That’s a tall order, to say the least. So I was skeptical.

But Bigot’s system is more than a gimmick with an app (though there is one of those too). There is some real sense to it. The Bigot Index, as he calls it, encompasses more than the usual vintage-quality metrics of seasonal conditions, temperatures and ripeness. By getting into deeper things like biodiversity, vine age and canopy, he makes a direct link between vines, grapes and the resulting wines.

“Everyone says the vineyard is the most important thing,” says Bigot, a tall amateur rugby player who wears a thick beard and ties his hair up in a man bun.

“But why? I want to better understand vineyards in a scientific way,” adds Bigot, who developed the index system as he has worked for prestigious Italian producers such as Piedmont’s Angelo Gaja and Conterno Fantino and Friuli’s Livio Felluga.

I am standing with Bigot in a Piedmont vineyard, specifically his client Giuseppe Caviola’s Bric du Luv vineyard in Montelupo Albese, which grows grapes for Ca’Viola’s flagship Barbera d’Alba Bric du Luv (2015, 93 points, $45).

These terraced vineyards, with sandy lime soils that slope to the southeast, scored 92 points on the Bigot Index in 2020. Just yards away, Caviola has an identically planted vineyard, oriented to the southwest, that has the same soil type, Barbera vines of a similar age and the same organic cultivation practices. But the wines from this vineyard are not as interesting or complex in the opinion of Caviola and wine critics.

“So what makes this vineyard produce great wines and that vineyard only good ones?” Bigot asks.

Excuse me, but here things get necessarily nerdy.

The Bigot Index measures nine factors: overall production per plant, the amount of foliage, the foliage-to-fruit ratio, grape health, bunch formations, annual hydric stress, plant vigor, biodiversity in soils and the age of the vineyard.

These factors can be influenced by the natural elements of terroir (such as elevation, sun exposure and soil composition) and vintage conditions, as well as vineyard management. They also connect in interesting ways. Ideally a little hydric stress is good; too much is a disaster, though old vines resist dramatic changes best. Bigot believes that every vine should have roughly a square yard of leaf surface per pound of grapes. And soils should have at least 20 groundcover species to ensure a good balance of minerals for healthy plant growth and the production of quality yeasts for spontaneous fermentation, which Bigot heartily endorses: “If you are not using indigenous yeasts, you are not using all your potential.”

 Giovanni Bigot and Giuseppe Caviola standing and talking with glasses of wine in hand
Ca’Viola proprietor Giuseppe Caviola, right, says his work with Giovanni Bigot has helped him better understand the nuances that can make a vineyard great versus simply good. (Robert Camuto)

So what is the difference between Ca’Viola’s two vineyards here?

The main difference is Bric du Luv’s vines are of medium vigor because of the soil composition and therefore produce looser bunches; that allows for better circulation of air and more even exposure to sunlight, making for healthier grapes. The neighboring vineyard, by contrast, has highly vigorous vines that produce tighter bunches, which are more susceptible to disease. Additionally, the warmer southwestern exposure means more chance of sunburn on the grapes, resulting in more fruit lesions and hence a more rustic wine.

When it comes to grape health, Bigot looks for all sorts of scarring that can come not only from overexposure, fungi, mildew and disease but also from all manner of vineyard treatments, be they conventional, organic or biodynamic.

“Just because it’s organic doesn’t mean it doesn’t harm grapes,” Bigot says. “Any product not well-applied can harm grapes.”

Bigot looks at vineyards as complex ecosystems impacted by both nature and man. Most of his clients farm organically or biodynamically, but he prescribes no method of growing. His is merely a way of measuring viticultural strengths and weaknesses.

“After that, you have to rely on the gentle hand of the winemaker not to destroy it,” he says.

Bigot grew up in Cormons, near the Italian-Slovenian border, not far from producers such as “orange wine” pioneer Radikon (now a client). Bigot and his family produced wine on 12 organically farmed acres that they sold through their bed-and-breakfast. At university, he studied enology and agricultural science, continuing with post-graduate research on beneficial organisms in vineyards.

After working six years as agronomist for the Collio and Friuli Isonzo appellations, he struck out on his own as a consultant in the mid-2000s and started research on environmental factors that led to the best aromatic expressions in Sauvignon Blanc. Bigot consulted acclaimed agronomy and enology experts in France, Italy and throughout Europe. His published work confirmed his international standing as a Sauvignon Blanc expert and resulted in his first list of vineyard influences on wine quality, with a half-dozen factors.

“In enology research in Italy, they never talk about vineyards. And in viticulture, they only talk about grapes, not wine,” he says. “My idea was to marry the two—to bring together two separate worlds.”

Bigot and his Perleuve consulting company have expanded outside of Friuli to consult across Italy for a total of about 80 clients. Last year, he completed his index with nine factors for gauging vineyards.

At his winery in nearby Dogliani, Caviola praises the Bigot Index, saying, “It has helped me with the understanding of the potential of terroirs.”

“There is little that separates good and great,” Caviola adds. “But there’s a whole world of little differences between the two.”

The Bigot Index is a malleable work. He tweaks parameters according to categories of white, red and sparkling wines, as well as variety. And it’s all based on satisfying today’s tastes for wines that are fresh, balanced and complex.

“At the end of the 1990s, the most appreciated white wines had low acidity and were big and buttery. Now that’s changed,” he says. “If tastes change again, we will have to change the index.”

Bigot clearly has his preferences. No index can perfectly measure everything that influences wine, its flavors and magic. But I think that finding methods to discuss vineyards in ways that are both holistic and scientific can only help us all.

People Vineyard Management Italy

You Might Also Like

Sommelier Roundtable: What’s Your Favorite Valentine’s Day Service Story?

Sommelier Roundtable: What’s Your Favorite Valentine’s Day Service Story?

8 wine pros dished about dates gone wrong, proposals gone right and the bottles that were …

Feb 4, 2023
The Comeback of a Cool Piedmont Red

The Comeback of a Cool Piedmont Red

Grignolino—the “un-Barolo”—takes a place at the table

Jan 18, 2023
Sommelier Roundtable: What Was the Best Wine You Drank in 2022?

Sommelier Roundtable: What Was the Best Wine You Drank in 2022?

11 top wine pros shared which bottles were the highlight of their year

Jan 13, 2023
A New Era for Hanzell

A New Era for Hanzell

Director of winemaking Jason Jardine innovates at this historic Sonoma estate

Dec 15, 2022
The Wine Viking at Home in Sicily

The Wine Viking at Home in Sicily

Peter Vinding-Diers has left his mark from Bordeaux to South America to Hungary. He’s …

Jan 5, 2023
Sommelier Roundtable: What Is Your New Year’s Wine Resolution?

Sommelier Roundtable: What Is Your New Year’s Wine Resolution?

11 top wine pros shared their wine goals and aspirations for 2023

Dec 30, 2022