If you love tiki, you love orgeat, the sweet and lightly floral almond syrup that serves as a staple ingredient in famous drinks such as the Mai Tai, Fog Cutter, and Eastern Sour. Despite its critical role in some of the most classic cocktails, orgeat can cause confusion for even experienced drinkers. To sort out orgeat’s origin story, VinePair spoke with cocktail expert Martin Cate, owner of San Francisco’s famed tiki spot Smuggler’s Cove, and the author of “Smuggler’s Cove: Exotic Cocktails, Rum, and the Cult of Tiki.”

Cate says that orgeat — pronounced or-ZHAT — is actually the French word for barley, making it a name that ties into the origins of this ingredient. For many centuries, the French would make barley syrup after harvesting the crop as an effective way of storing calories and nutrition through the winter. Cate says that barley syrup isn’t so enjoyable on its own, which is why somewhere from the 17th to 19th centuries, the French started adding almonds to the concoction to give it a more pleasant flavor.

Eventually, the proportion of almonds to barley became so unbalanced that orgeat just became an almond syrup, and the barley was completely phased out. In today’s iteration, orgeat is slightly floral thanks to the use of orange flower or rose water.

Get the latest in beer, wine, and cocktail culture sent straight to your inbox.

“Today, people are making all kinds of orgeats with different nuts,” says Cate. “There’s a macadamia nut orgeat. In my bars, we have an ‘oat-geat’”

Even before the arrival of tiki culture, orgeat was occasionally used in cocktails predating Prohibition. Jerry Thomas even used it in his famous Japanese Cocktail in the 19th century. But according to Cate, this ingredient always had a role in the development of tiki thanks to Trader Vic, the creator of the Mai Tai, and a trailblazer of tiki culture.

During his childhood in Northern California, Victor Jules Bergeron’s parents owned a grocery store, and since they were both French and French Canadian, orgeat was something that the family sold. When Victor started making tropical cocktails under the name “Trader Vic,” he incorporated orgeat into his concoctions because it was a flavor he knew well. “It’s a very happy accident because it just so happens that this is an ingredient that works spectacularly well with rum and lime juice,” says Cate. “It’s very complementary to add that nuttiness to rich rums.”

Cate especially recommends using orgeat in a Daiquiri, which can always benefit from a hint of nuttiness. “I think orgeat is such an important part now of the vintage tropical drink canon that you’ve just gotta have some,” he says. “It’s really flexible, and overall, it’s a pretty critical ingredient.”