So, why do servers “flame” things like Bananas Foster at the tableside? Obviously, for the tips. Greek waiters long ago realized the connection between pyrotechnical displays and gratuities, which is how saganaki came into being. It all started in Chicago back in 1968 when the owner of The Parthenon, a legendary Greektown restaurant, first thought to merge kasseri cheese, brandy, flame and a loud shout of “Opa!!!” into one grand food-theatrical gesture. The thing caught on like, er, wildfire, and today waiters the world over dash through dining rooms trailing plumes of flame, leaving naught in their wake but the scent of burning eyebrows.
This is not to say there aren’t practical reasons for dousing food in flaming alcohol. Alcohol is an excellent solvent, and when it’s applied to certain flavorful compounds, causes their molecules to disperse, sending them flowing over our taste buds in rivers.
The sheer volatility of alcohol (i.e. it’s ability to throw off molecules into the surrounding air) also plays an important role in the flambé experience. Yes, it’s the alcohol vapor that’s responsible for the flames in the first place. However once the flames die down, there’s still quite a bit of liquid alcohol left in the pan. About 75% of what went in, in fact. That alcohol continues to evaporate once the dessert hits the plate, only now it isn’t evaporating alone. It’s taking small amounts of other sauce components with it, which is to say it’s creating aromas, and aromas are critical to the overall sensation of flavor.
Of course the fire has a big impact in its own right, caramelizing the sugars and in the process bringing molecules into being that taste all sorts of different ways, from bitter to sour to fruity.
Thus when that tuxedoed waiter lights up his pan of bananas and brown sugar — FOOM! — there’s more going on than mere showmanship. Flavors are being added, yes, but they’re also being altered, amplified, even created. A pretty impressive alchemical feat is what it is. Who says showbiz is all flash and no substance?