We hear of the conversion of water into wine at the marriage in Cana as of a miracle. But this conversion is, through the goodness of God, made every day before our eyes. Behold the rain which descends from heaven upon our vineyards, and which incorporates itself with the grapes to be changed into wine; a constant proof that God loves us, and loves to see us happy! — Ben Franklin
To take wine into our mouths is to savor a droplet of the river of human history. ― Clifton Fadiman
A long, long time ago near the dawn of civilization, someone likely found a jar of fruit juice past its prime. He drank it and probably felt slightly buzzed.
Wine would transform society, including religious life. The Israelites, for example, offered a fermented drink daily to God along with their burnt offerings. And followers of Christ have reverently shared in the cup of wine to remember the sacrifice of Christ’s blood.
Without much understanding of the science until the last couple hundred years, people used trial and error to develop the art of winemaking. Archeologists believe winemaking to be an almost 7,000-year-old tradition. Patrick McGovern, known as the Indiana Jones of ancient fermented beverages, used chemical analysis to date residue inside jars found in the Zagros Mountains in eastern Iran to 5400 B.C. He believes the ancestor of all modern grapes was located somewhere in the region. He calls it the Noah Hypothesis, named for Noah’s priority to plant a vineyard (Gen. 9:20) after landing on Mt. Ararat after the Flood.
Wine needs grapes, of course. But the magic ingredient was too small for humans to see or even know about for thousands of years.
Crushed grapes—seemingly dead, inedible, rotten even—spring back to life again after being left in jars for a long time. To the naked eye, little bubbles appear out of nowhere. Bubbling and churning, liquids previously idle and still become something else entirely.
“Early winemakers must have marveled at the seemingly miraculous process of fermentation,” McGovern writes on his lab webpage.
Fermentation in bread probably was used before wine, according to archeology. In the Bible, leavened bread was made by using a piece of dough already left to rest naturally, incorporating the yeasts and bacteria in the air (a similar process to making sourdough bread). Interestingly, in parts of the Roman Empire—and probably in Jesus’ lifetime—the must of grapes or the foam skimmed from beer was sometimes used to leaven bread.
However, while ancient people knew how to leaven bread or ferment wine, they had never seen yeast.
In the 16th century, Antoni van Leeuwenhoek, now known as the father of microbiology, was the first to observe yeast. He didn’t know what its purpose was. But by Samuel Johnson’s 1755 Dictionary of the English Language, the world knew: it’s “the ferment put into drink to make it work; and into bread to lighten and swell it.”
And yet, scientists of that day did not understand yeast to be alive, thinking it was a chemical compound. Eventually, more powerful microscopes enabled scientists to watch yeast multiply, fermenting sugars into alcohol.
Seeking to help the French wine industry figure out why some wine turned bitter instead of fermenting properly, Louis Pasteur performed experiments in the 1850s that led him to conclude that yeast had to be alive to produce wine. Pasteur defined fermentation as respiration without air because the process occurs without oxygen.
The “magic” of fermentation occurs inside this tiny one-celled microorganism. It took chemists almost 100 years to identify the first chemical reaction that occurs during fermentation. Over the years, numerous scientists demystified the mystery of fermentation, sleuthing how many reactions there were and in what order they occurred. In 1940, the whole of their research clearly explained step-by-step the process now known as glycolysis. We now know that the complete glycolytic pathway within yeast cells actually takes ten chemical reactions to produce alcohol.
When grapes are crushed, yeast already present in the grapes begins to ferment. (Modern winemaking sometimes uses cultured yeast, which is more predictable.) In one or two weeks, yeast cells feed on the sugar in the fruit, converting glucose into energy, which the yeast uses to reproduce. In the process, it lets off carbon dioxide. After pressing the grapes, any bacteria still present will continue to ferment into a lactic acid in a slow three to six months of additional aging.
Fermentation also occurs in yogurt, kimchi, and bread when bacteria (instead of yeast) convert sugars into lactic acid. Its role in ancient life (and modern life!) was vital: It allowed foods to be preserved beyond their typical shelf life. Grapes last for a few days. Wine is meant to last for a season. Most wines taste best when drunk within a few months of harvest, up to about one year. But for centuries wine has had a reputation for getting better with age. As far back as the Roman Empire, the finest wines aged for decades.
Wines hundreds of years old still brim with life. In 2010, a Finnish diver took a swig of champagne from a shipwreck at the bottom of the Baltic Sea. The shipwrecked wine outdates some of the oldest wine in private collections by decades and is nearly two centuries old. The cork on the bottle popped open from the change in pressure while it was being moved. The divers rushed it to sommelier Ella Grussner Cromwell-Morgan.
“There was a freshness to the wine,” she reported. “It wasn't debilitated in any way. Rather, it had a clear acidity which reinforced the sweetness. Finally, a very clear taste of having been stored in oak casks.”
I find it remarkable that we can not only drink grape juice that started to “go bad” in Napoleon’s day, but that it tastes great, too. I thought about it as I dipped my bread into the wine cup this week. I’ve often thought about how the church has celebrated Communion for 2,000 years. But this time I thought about the antiquity of the wine, too. What would it have meant to those disciples in the Upper Room? Surely, they understood that wine goes through a mysterious transformation, but we can now describe that process. What new meaning can we find? What might they have thought if they knew that yeast—the fungus deliberately left out of their Passover bread—was what had changed the grapes to wine?
As Jesus offered the bread and wine, he knew all there was to understand about wine. He told them, “This is my blood of the covenant, which is poured out for many for the forgiveness of sins.” Did they think the momentary life of a grape transformed into a drink that abides? Did they think about the mysterious life bubbling and breathing inside crushed grapes?
I’ve thought much about Jesus’ blood. But when Jesus held the cup, what was it about the wine he wanted me to notice? Like Christ’s death itself, it’s a bit much to consider all of its implications at once. So I thank God for it all and let its mysteries gladden my heart.
Rebecca Randall is The Behemoth’s science editor.
