Oleo saccharum (ole-o-saka-rum)
David Wondrich's seminal book on punch makes two very important points about the convivial cocktail fore-runner:
1. Well-made punch has nothing to do with Kool-Aid, sherbet or ginger ale, and 2. It's impossible to make most punches well without oleo-saccharum.
Oleo-saccharum's uses aren't limited to the punch bowl. The aromatic base syrup is also an important component of cocktails that call for a citric edge.
To make oleo-saccharum (the phrase translates as "oil sugar," but everybody uses the Latin), bartenders muddle lemon zest with very fine sugar. At least, they usually use lemons: Oranges, limes and other citrus fruits work, too.
The mixture has to rest for at least an hour, so advance planning is essential.
"This process is admittedly time-consuming and to some degree a laborious one," Wondrich writes in a passage quoted by Portland bartender Jeffrey Morgenthaler, who's devised a vacuum-sealed shortcut.
The Gin Joint (The Swap Meet, made with meyer lemon oleo, gin, basil, lemon juice and cane sugar, $7.)
Although the word "oleo-saccharum" doesn't always make the menu, look for the syrup wherever punch is served. Local bars with punch programs include Husk and Edmund's Oast.
Unfortunately, you're on your own. You'll need lemons, sugar and plenty of time. But if you want to purchase a taste of what oleo-saccharum does for a drink, the syrup figures into Bittermilk's bottled mixers. The locally made compounds are sold at stores, including Caviar & Bananas, Charleston Beer Exchange and Two Boroughs Larder.