By Andrea Elmore
Flambéing is a dramatic cooking technique in which a dish with alcohol is set alight at the table, but does it change the flavor, or is it all for show? What actually happens to food when a spirit is added and ignited?
Christine Hansen, a senior Viticulture and Enology major, set out to answer these questions when she began researching flambé her sophomore year at Cornell. Hansen's two years of research have turned into a senior thesis, and this past spring, Hansen was one of six undergraduates selected to present her research at the American Chemical Society in San Diego as part of the Ag & Food Division's Undergraduate Symposium.
The road to this research began four years ago, when Hansen was a freshman in Cornell's College of Engineering.
"During my freshman year, I took my first viticulture and enology course and loved it," admitted Hansen. "I transferred into the major and have never looked back!"
During a class on wine and grape analyses in Hansen's sophomore year, assistant professor Gavin Sacks presented a lecture on measuring ethanol in wine and spirits.
"He offhandedly suggested that it would be an interesting undergraduate project to find out what—if anything—is actually happening when the flambé technique is used," she said.
She approached Sacks after the lecture to express her interest.
"I was surprised at first that she had called my bluff," said Sacks. "But the more I thought about it, the more it seemed like a good question to consider. Previous research had shown that a small amount of ethanol is removed during flambé. It wasn't clear if flambé was otherwise changing the flavor of a dish, but it's worth knowing since it's a potentially dangerous technique."
In her experiments, Hansen prepared a caramel sauce, similar to what is used in Bananas Foster, using flambé. As a control, she also prepared a sauce which was heated but not ignited, and a third sauce which was neither heated nor ignited. The sauces were then subjected chemical and sensory analysis.
"Surprisingly, the ethanol content of samples that were ignited—as in flambé—were nearly identical to those that have just been heated," said Hansen. "While there are small differences in the final ethanol concentration, almost all of the ethanol and water loss can be explained by evaporation and not the actual ignition."
Hansen also investigated the claim of some cookbooks that browning reactions, important to the flavor of grilled meat and roasted coffee, may occur during flambé. Using temperature probes, she determined that although the temperature of the flame in flambé can reach >1300 °F, the temperature of the food surface never exceeds the boiling point of water, which is too cool for browning reactions to occur. She found no chemical evidence of browning.
Finally, a sensory panel could generally not distinguish between an ignited sample and a heated sample.
"Christine's research suggests that the major contribution of flambé is to look spectacular," said Sacks. "The other changes that occur, like the removal of ethanol, can be assigned to heating alone. If the show is unnecessary, for example if flambé is being performed in the kitchen rather than tableside, there may be safer ways to remove ethanol from the spirit during cooking."
Hansen will be graduating this May with a major in Viticulture and Enology and a minor in Food Science, and next fall Hansen will be putting her research experience to good use as she pursues a master's degree in Food Science at Cornell. Aside from honing her lab technique and presentation skills, her research taught her some valuable lessons.
"My undergraduate research made me realize that things don't always go as planned—it's actually rare," she said. "It is important to be persistent."
Andrea Elmore is undergraduate coordinator for the Viticulture Enology program housed in the food science department at Cornell.