Juice turns into wine

As the sun was setting and our legs grew tired, the yeasts on the crushed grape skins and in the air were getting ready to get to work. If you ask me, fermentation is one of the great wonders of our natural world: yeasts feast on the sugar in grape must and turn those sugars into alcohol and CO2. Which yeasts get to work and how they get into the juice is dependent on the winemaking style. In conventional winemaking, cultured yeast strains are used – that is, yeasts that are selected and come in a pack (much like yeasts you can buy in a supermarket to make bread). Those yeasts are then added to the grape juice and become the dominant yeast strain in the vessel. This results in a predictable fermentation and allows a degree of control over the outcome. Spontaneous fermentation, by contrast, means that there is no intervention by the winemaker. Whichever yeasts are floating in the air, in the winery and on the grape skins, are the yeasts that will get to work, colonize the must, fight for the sugars and do the fermentation. Naturally, this means that the outcome is less certain. It may take longer for the fermentation to complete and because of the variety of wild yeasts that exists, competing yeast strains may give a slightly different aroma profile.

To power their work, yeasts need nutrients. Cultured yeasts typically need to be fed during fermentation. It is exactly as it sounds: someone hangs over a tank and drops a mixture of nitrogen, amino acids, vitamins and minerals in the fermenting must. I was that person at Corazón del Sol where I worked during the day. Within seconds of dunking the food in the tank, the must would start bubbling as yeast cells were rising up to eat. Wild yeasts however do not need to be fed. Because when grapes are healthy and untreated, the must contains everything the wild yeasts need to complete a fermentation. Yeasts and grapes have evolved together and this results in a perfect symbiosis between grapes, yeast cells, acids, minerals and vitamins. We wanted our wines to reflect that wonderful ecosystem and spontaneous fermentation with wild yeasts is one of Nova Radix’ core winemaking principles.

By the next morning, NR1, our white wine, was already fermenting. Our red wine was split in two tanks: one filled with whole bunches of grapes that we did not crush so the grapes could start fermenting from within the berries and one filled with crushed bunches that would ferment in the same way as our white wine. Both tanks started fermenting a couple of days later – without any issue, because the fruit was so intact and the vineyard so pure that the wild yeasts had everything needed to do their magic.

The ability to turn one thing in a better thing is a skill Argentinians share with yeasts. When you live in an economy with hyperinflation, where 1000 pesos today may be  worth only 750 pesos tomorrow, it is safer to rely on the intrinsic value of goods than on the cash in your wallet. That is why it is not uncommon to see barrels be traded for an hour of work, gas for bread, the use of a forklift for a lab analysis, and of course, wine for everything. It is one of the biggest lessons I learned: when man-made systems crumble, do not despair but follow nature’s lead and create a mutually beneficial ecosystem with those around you to turn life’s juice into life’s wine.