4.92 oz mixed with ice, 1.23 oz of it pure alcohol
Melt
Shaken: +20 % of the pre-batch, +0.98 oz of water
Served
4.92 + 0.98 = 5.9 oz in the glass
Strength
1.23 ÷ 5.9 = 20.8 % ABV as served
Ethanol
1.23 oz × 29.57 ml × 0.789 g/ml = 29 g · about 201 kcal from the alcohol alone
IN THE GLASS
VANILLIN
FROM RUM + BRANDY OAK · from oak barrel aging
Formula
C₈H₈O₃
Mass
152.15 g/mol
IUPAC
4-hydroxy-3-methoxybenzaldehyde
Bourbon's fingerprint, extracted from the charred American oak the law requires for aging. Same molecule as the vanilla bean's signature, so a well-aged bourbon legitimately tastes like vanilla. Chemistry, not metaphor. Cognac, aged rum, tequila reposado all extract vanillin from oak too. Different barrels, same molecule.
Lemon's defining note: technically a mix of two geometric isomers (geranial and neral) that read as the same aroma to the nose. Lemon peel, lemongrass, lemon verbena, and Indian chai all carry it. In cocktails it's what a lemon twist contributes that lemon juice can't: the volatile expressed from the oil glands, not the acid from the pulp.
The grape-candy / Welch's-grape-juice aroma. Concord grapes carry it in concentrations no European wine grape (Vitis vinifera) approaches; American Vitis labrusca grapes, native to the northeastern US, hold methyl anthranilate as a signature. The "foxy" note in North American grape juice and artificial grape candy both come from the same molecule. Also used as the standard bird repellent on commercial fruit crops; birds find it intolerable.
Rum, brandy, gin, two citrus juices, orgeat and a sherry float. Three spirits, all in meaningful quantities, carry the strength. The sherry float is the finish: nutty oxidative aromatics that anchor the otherwise fruity top. Trader Vic printed it in his 1947 Bartender's Guide.
PROVENANCE
Victor Bergeron created the Fog Cutter at Trader Vic's in Oakland in the mid-1940s. Vic's own quip was that after two of them nobody would see the fog at all, a nod to its considerable ABV. Three spirits in one glass was unusual at the time; the sherry float was Vic's signature finishing technique. The drink fell out of standard repertoire as the tiki era faded in the 1970s; Beachbum Berry's 1998 Grog Log restored it. Now a craft-tiki standard.
