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As a kid, Ross Flom often watched his Norwegian grandmother make coffee. Before brewing, she would add a raw egg — shell and all — to the grounds.

They also made coffee this way at the Lutheran church in Flom's hometown in southern Minnesota.

"As a child I was offered a cup of this brown hot water-looking concoction and quickly passed on the opportunity," Flom said. "To this day I have never had a cup of coffee — with or without the egg."

"Is this tradition local to Minnesota? Scandinavian tradition?" Flom, who now lives in Cedar City, Utah, asked our reader-driven reporting project, Curious Minnesota.

To find out, we first turned to Jim Zieba, the state's resident egg coffee expert. For decades, he has spent the last twelve days of summer brewing egg coffee in the kitchen of the Salem Lutheran Church Dining Hall at the Minnesota State Fair. It's boiled, he said, not percolated, a whole egg and its shell added to the grounds beforehand to bind them and smooth out the taste.

Lighter in color than a regular cup of joe, it's called "Swedish Egg Coffee" on the big sign with a blue coffee pot above the dining hall. But when Swedes come to Zieba's dining hall at the fair, they tell him they've never heard of it.

"It originated more with the Swedish immigrants to the United States in the 1800s. It was always a staple at the many Lutheran church potluck dinners, and is sometimes called 'church basement ladies coffee,'" explained Zieba. "I'm not aware of the exact chemistry, but I know that coffee tends to be slightly acid, and eggs are alkaline, and the two cancel each other out, so you end up with a brew that is very smooth, and not at all bitter. The egg also clarifies the coffee."

Growing up, Zieba's Swedish grandmother and aunts always prepared egg coffee, he said. "But it involves tending to it. And when my mother got her new Silex automatic coffee maker, that was the end of egg coffee in our household," he said.

Scandinavian origins

Egg coffee likely emerged from habits that were once common in rural Scandinavia centuries ago, explained coffee writer Asser Christensen, who is Danish.

"The concept of egg coffee, particularly a specific Scandinavian variety, is virtually unknown in contemporary Denmark, Sweden and Norway. It is no longer part of our culture," he said. "However, in the 1700s and 1800s, it was common for farmers in rural parts of Scandinavia to use various substances to clarify their coffee."

In those days, coffee was a luxury, he said. So farmers would reuse the same grounds for several days. The resulting "murky" brew led them to seek out ways to clarify it.

"While there are accounts of eggs being used, it is more likely that dried fish skin and ground deer antlers were even more prevalent," Christensen said.

Scandinavian immigrants likely brought those unconventional filtration methods to the U.S. and kept it up because they felt it was part of their cultural identity, he said.

"Meanwhile, Scandinavian coffee drinkers back home felt no nostalgia for egg coffee," he said. They embraced filtered coffee pots and never looked back.

"Like many old Scandinavian food traditions, while it is forgotten in the mother countries, it continues to be practiced in Minnesota as a way to honor those who brought us here," said Patrice Johnson, author of "Land of 10,000 Plates: Stories and Recipes from Minnesota."

Although it became a Minnesota tradition, egg coffee was also popular in other parts of the Midwest where Scandinavian immigrants settled (as evidenced by the "Norwegian egg coffee" still sometimes served at the Grand Forks Sons of Norway lodge.)

More than two dozen church dining halls — many serving egg coffee — once filled the grounds of the State Fair. Today there are just two church halls at the fair, and only Salem keeps the now-faded immigrant tradition of egg coffee alive. When the Minneapolis Tribune profiled Salem Lutheran's hall in 1959, the pastor was in charge of the coffee.

"We make egg coffee. Only way," congregant Signie Johnson told the paper.

Twenty-six years later, Salem Lutheran Church Dining Hall waitress Olive Hughes told the Minneapolis Star and Tribune that it was their egg coffee that drew early-morning crowds: "They'll walk clear across the fairgrounds to get a couple cups of it. Even before they eat, they'll drink two or three cups."

At that time, the price was 25 cents and bought unlimited refills.

While the price has gone up to $3, not much has changed with Salem's recipe through the years. Zieba said they once used traditional white porcelain enamel pots, but switched to stainless steel since "that's what the health department wants nowadays."

'A lordly drink'

Before automatic drip coffee makers took over in the 1970s, egg coffee was popular at home, at church and in many drugstore counters, diners and cafes in Minnesota. The Swedish immigrant fellowship hall called Gustavus II Adolphus Hall that once stood on E. Lake Street in Minneapolis was also known for serving egg coffee.

In 1960, Minneapolis Tribune columnist Charles Guthrie gave the beverage high praise: "Whenever entertaining a large group, we employ a 30-cup enamel pot and stir an egg into the coffee before consigning it to the steaming vat. This invariably makes a lordly drink."

As it turns out, current Star Tribune food and drink reporter Joy Summers also loves egg coffee. She has called a cup of Zieba's brew from the Salem Lutheran Church stand "hand-held paradise."

Summers learned how to make it from her Iron Range grandma. "She would always show me, 'You have to mix in the egg just until the grounds glisten.' So it's very much that grandmotherly-type cooking where there aren't measurements. It's a sensory experience," she said.

Here's how she explained the science behind the brew in 2016: as the mixture boils, the egg white, a clarifying agent, separates into proteins that then bind to impurities and other macromolecules, pulling out acrid and bitter flavors. The grounds and egg clump together into "a raft" that will sink to the bottom.

Egg shells were not included in her family, said Summers, who also advised that basic grounds (like Hills Bros. or Folgers) work best.

There is at least one place you can find egg coffee year-round in the Twin Cities, said Summers. At Myriel in St. Paul, chef Karyn Tomlinson, known for pairing her Minnesotan and Scandinavian heritage with her French culinary know-how, serves a cup with dessert. (In a review of the restaurant, the Washington Post called the drink "velvety.")

In the spirit of curiosity, I tried a cup on a recent evening — and found that it was, indeed, smooth, maybe even "velvety." Smooth enough, at least, for me to forgo my usual splash of milk and drink it black.

How to make egg coffee

Here's the recipe for egg coffee that Zieba uses during the fair:

Fill a 40-cup pot with cold water and bring it to a rolling boil.

Put two cups of coffee grounds in a saucepan and mash in one egg. Mashing in the egg in the shell is optional, and I include the shell just to avoid handling the egg whites and yolk. Reduce the heat on the boiling water and dump in the coffee grounds.

Allow the brew to come to a rolling boil for about 30 seconds.

The timing is not critical, and the brew will foam heavily at first, then thin out. At this point the heat is removed and the grounds allowed to settle. A cup of cold water poured on top will speed settling of the grounds.

If you aren't expecting a crowd, here's his suggestion for a smaller pot:

For a ten to twelve cup brew, whip up an egg in water to about the consistency of French toast batter.

Measure out three or four tablespoons of coffee and saturate the grounds with about a fourth to a third of the batter.

Store the remainder in the fridge for future brews. Then dump the grounds in the boiling water and start your brew. Adjust the heat to prevent boiling over. Then remove from the heat and allow the grounds to settle.

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