Making wine Part 6–Harvest, winery decisions

Good wine is made in the vineyard. The winemaker’s job is to allow fruit the grape grower delivers to express itself.

Harvest is moment of truth. In higher quality wine, grapes are harvested at night or in early morning when the grapes are plump and past the stress of afternoon sun. The grape farmer has spent the previous weeks ascertaining the harvest date and securing skilled laborers or mechanical harvesters to bring in the grapes.

Harvest grapes too early, you get tart, thin-tasting wines with too much acidity and not enough richness or mature grape flavors.

Harvest too late, you get grapes that lack balancing acidity and are overly ripe, producing “flabby” wines.

Harvest goes well. Now decision making shifts to the winemaker. Do you de-stem the grapes—separating berries from attached stems? Stems—and seeds—provide tannins and other character to the wine. Or do you go with whole cluster fermentation where there is no de-stemming? Whole cluster can add complexity by increasing spice and herbal flavors, emphasize fruit and tannin structure, and smooth out high acidity. Vintners can de-stem part of the harvest, whole cluster another part.

You also can choose carbonic maceration. Carbonic maceration is done with whole clusters in a carbon dioxide-rich tank, eliminating most of the oxygen. In carbonic maceration, fermentation occurs inside the grape. Resulting wine is very fruit-forward with low tannins. It is ready to drink very quickly, but lacks structure and tannins for aging. Beaujolais nouveau is best known wine using this technique. Beaujolais nouveau is at its best less than two months after bottling.

No matter what technique you use, the juice now is ready for fermentation. Another big decision presents: what yeast do you use to start conversion of grape sugar into alcohol and turn grape juice into wine?

Natural yeast is that which is available in the vineyard and winery. Natural yeasts are more challenging because the winemaker concedes control to whatever Mother Nature provides. Many winemakers believe natural yeasts produce more complex aromatics and better reflect terroir.

Commercial yeasts give winemakers more control over fermentation. This usually results in very consistent wines vintage after vintage—a plus for large production facilities, but not as attractive to people who prefer artisanal efforts.

Next week: Let the fermentation begin.

Last round: A day without wine is like… Just kidding. I have no idea what that day would be like and no desire to find out.