By Tim Bean

When Congress passed Prohibition in 1920, Americans called upon their natural ingenuity to skirt around its sweeping restrictions. “Medicinal” liquor, bootlegged liquor and moonshine, and speakeasies were just a few of the methods used, but the most ingenuous had to be the wine bricks sold by California vineyards.

Wine bricks—compressed cakes of concentrated grape juice—provided an imperfect solution to the California vineyard owners staring down the bankrupting barrel of the 18th Amendment. These vineyards spent decades cultivating and breeding specific grape strains for wine, but Prohibition had made their art illegal overnight. Owners did not want to abandon their vineyards, since the eventual failure of Prohibition was obvious only a few years after its passage. Vineyard owners needed enough income to maintain their signature crops for the amendment’s eventual repeal.

Wine bricks varied in size and were often sold by third-party companies, like Vine Glo and Vino Sano, which purchased them from California vineyards. The Volstead Act (the nuts and bolts of Prohibition) allowed families to manufacture up to 200 gallons of nonintoxicating fruit juice without penalty. This meant the wine bricks could be freely bought and sold. Making grape juice from these compressed cakes was as simple as dropping them into water and stirring.


This created another problem: how did consumers turn the grape juice into wine? It wasn’t illegal to sell the wine bricks, but it WAS illegal to knowingly sell supplies for wine-making. It was also illegal to teach consumers how to make wine. Slapping instructions on these cakes proved intent for both of those restrictions.

Instructions: After dissolving the brick in a gallon of water, DO NOT place the liquid in a jug away in a cupboard for twenty days, and DO NOT store it in temperatures above seventy degrees, because then it would turn into wine. 

~Actual caution label on California wine brick

The solution was elegant and utterly ridiculous. On paper, the companies intended only to sell grape juice and did not want buyers “accidentally” making wine from these bricks. To prevent this, companies printed the details of fermenting the grape juice to make wine, as a warning label. The companies’ real intent was obvious, but this tongue-in-cheek tactic was enough to remain within the law.

Section 29, Volstead Act

Although originally intended to provide a simple sustenance income for American vineyards, many became wealthy from their sale. This boon was a direct result of the absolute failure of Prohibition. The National Bureau of Economic Statistics discovered that while alcohol consumption in the US fell 70% immediately after Prohibition’s passage in 1920, it increased steadily as the years went on. By the time Congress passed the 21st Amendment, America’s alcohol consumption was unchanged, possibly because the country perfected its clandestine drinking methods.

Today, California vineyards (which originated as personal gardens of Spanish missionaries to provide wine for Mass) are the fourth largest producer of the world’s wine, and Napa Valley one of the state’s most popular tourist destinations. There is little doubt that the oldest and most prestigious of these vineyards might have faded into history, if not for wine bricks.

If you’re enjoying this story, check out Mysteries of the Midwest, a collection of our most popular stories out of America’s Heartland, available on Amazon now in paperback and e-book.