Which traditional winemaking technique in Portugal’s Douro Valley has been temporarily suspended due to the Covid-19 pandemic?
A. Fermentation in open-topped tanks
B. Use of native yeasts—all grapes now treated with sulfur before entering winery
C. Hand-sorting grapes prior to crushing
D. Foot-treading grapes prior to fermentation
Treading grapes by foot was standard in the Douro Valley of Portugal for centuries until electricity came to the region (in the 1970s!). After that, standard grape crusher/destemmers were used. However, some grapes in the region are still trodden by human feet—especially grapes intended for vintage Ports. (I have fond memories—and pictures I’ll never reveal—of stomping grapes at Quinta do Vesuvio until 2:00 a.m.) But this treasured tradition requires crews to stand arm-in-arm down the length of lagares (la-GAR-ays), shallow stone or cement troughs (about 2 feet/0.6 meters high), as they march through the slippery mass of newly harvested grapes. As the method is clearly incompatible with social distancing, this year all Port producers must rely on modern equipment instead. Symington Family Estates, owner of Quinta do Vesuvio, has suspended foot-treading at the property for the 2020 harvest – believed to be the first time Vesuvio has done so since the winery opened in 1827. “We very much hope that we will return to foot-treading at Vesuvio as soon as it is safe and responsible,” says Rob Symington. Why cling to a costlier and more labor-intensive method? As it happens, the human foot is ideally suited to crushing grapes. Treading breaks the grapes, crushes the skins, and then mixes the skins with the juice for good flavor and color extraction—all without smashing the seeds, which contain tannin that is especially bitter-tasting. In the shallow lagares, the surface area of skins to juice is high, allowing color and flavor to be extracted extremely quickly. This is desirable because in Portugal, temperatures usually climb over 35°C (95°F) during harvest, precluding the languorous 6 to 12 days of maceration that wines in cooler climates enjoy. Also, since Port is a sweet wine, winemakers must arrest fermentation early in the process before all sugar is converted into alcohol—up to a week before a dry wine will conclude on its own. That leaves Port producers with about 48 hours in which to extract the maximum color and flavor from their grapes, not a week or two.