Agriculture

Marc, yeast, and terroir

Today, the first of a two-part series on the spiritual and environmental nature of wine, and what it can teach us about productive paths for our society as it works to reintegrate itself with the earth. I start with the notion that the world’s crew of über-technical winemakers (UTW) might draw a lesson from the coyotes. Here’s a bunch of grapes picked by the coyotes in October, that have resurfaced recently from under the snow:

Slow Ferment
Note that the juices of these grapes seem to be going into sustaining the skin.  The life hasn’t left this culture yet.

A grape is a living environment. It’s a miniature earth. Basically, it’s a capsule of acid, held within a skin, which is covered by yeasts, fungi and bacteria, that live in a dynamic relationship with each other. Here’s how all that looks over at the Lake Sonoma Winery.

Cross Section of a Wine Grape Source

A miniature planet. The biosphere I’m talking about is on the surface of the skin.This little planet, with its own biosphere, interacts with both the atmosphere and the subterranean processes of water and chemical flow brought to it by the vine’s leaves. 

The yeasts are not just freeloaders here. They protect the grape’s skin by fighting off fungi, and each other, as the grape grows and its acids transform into sugars. At the same time, the skin itself transforms into a complex chemical matrix of flavours, acids and colours. As we know from the technical science of winemaking, these some 200 flavours are transparent to human taste until they have been digested and transformed by yeast. In other words, the wine we taste is the record of a complex, living process, which humans have learned how to transfer from skins to juice — which is preserved by the alcohol the yeast give off while doing their work. (In the natural grape, this alcohol evaporates into the air.) To show you what this all looks like, here’s another grape cluster, that also has come through the winter, but has done so still attached to its vine:

A Story of Transformations

Water plus carbon dioxide makes acid, which later is transformed into sugar, which is then digested by yeast and transformed into alcohol, which evaporates. In the end, the grape is reduced to skin and seed — with its biosphere still intact, ready to bloom into a new season. If our coyote winemaker is to believed, the yeast colonies in the grape’s little biosphere use the grape to maintain the skin through a long, cool process, in which the skin seems to utilize the fluids of the grape itself to maintain its integrity. This little world changes over the winter months in a complex process of transforming chemicals into others — a process akin to the aging of wine.

The story of grapes and wine is the story of yeast, and the story of winemaking is in the control of the yeast’s processes. Different yeasts produce different flavours. I would expect the micro-environments of the grapes, on different parts of the vine, with different exposures to light, drawing from different roots in differing soils, with differing water flows, would produce different yeast communities throughout the vineyard, making the vineyard itself a complex, living system. To recreate the full flavour of a vineyard in a season, it would be necessary to blend these different communities. One Okanagan vineyard that uses and develops these communities is Blue Mountain Vineyard. One of their practices is the return to the vineyard of their marc, the mass of stems and seeds leftover after a wine pressing. In France, five centuries of this practice have led to vineyard environments with their own, site-specific yeast populations, which have led to the unique wines of each wine district. When the French speak of wine terroir, they speak of this living environment. When they drink wine, they drink an entire dynamic environment, the life of which continues in the bottle of wine, as it continues to age in a manner similar to the aging of berries left to their own through the winter. When UTWs from Australia, North America, or Australia, and so forth, speak of terroir, they speak of sun and shade, water and soil, and grumble at the French for being lost in monastic mysticism. No discussion gets wine bloggers so hot under the colour as terroir, and none is so important if we’re going to understand, live on, and celebrate our land. Here’s one man who is supporting this conversation. In contrast to the practice at Blue Mountain, most Okanagan marc goes to the landfill. Talk about poverty of imagination.

Terroir in the Making

What humans put into wine is what they get out on the other end, not only in flavour, but also in their capacity to bond with the land. Anything else is how they bond with each other. I think the first is a respectful approach to a living earth.

A Grape Berry by Another Name

The principles that make the earth a living planet, apply on a much smaller scale to grapes. Technical approaches that divide such a dynamic system produce technical products. It works the other way, though: by creating and drinking technical products, we discourage attention to a living earth.

Humans are like yeast. We are catalysts on the living surface of a dynamic sphere. Unlike yeast, however, we get to determine the products we want, and the dynamic field in which we live. I want to live in a living one.

Tomorrow: Off to the Rhine. An inspiring history of the spiritual nature of a terroir.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.