Imagine walking into a friend's kitchen and smelling some mouth-watering beef marinating on the countertops. And it ends up being some of the best beef you've ever had. When you ask your friend what her secret is, she says, red wine.
When you cook with alcohol, it binds to the fat and water molecules alike. Some flavors--such as herbs--are fat-soluble, meaning they dissolve best in fat; most other ingredients in the sauce are water-soluble. This means that in your friend's marinade, a cup of wine can dissolve all the flavor compounds to the meat more effectively than a water-based sauce would.
Plus, like high heat or salt, alcohol breaks down proteins in meat, a process known as "denaturing." So the wine in your friend's marinade helps tenderize the beef.
A common misconception about cooking with wine and spirits is that it all entirely "burns off." When you cook with wine--or any spirit--it doesn‘t all disappear.
Alcohol‘s molecules are volatile: they evaporate rapidly, which is why we often smell it so intensely. And since alcohol boils at 173 degrees Fahrenheit, versus water‘s boiling point of 212 degrees, the alcohol in your pot evaporates much sooner than water.
In fact, reduction, dilution, and a long cooking time are some of the best ways to reduce the percentage of alcohol left in your dish.
Thanks to Susan Ebeler of the University of California for reviewing this episode's script.
If you want to keep thinking about science and food, w e recently covered some of the science behind making butter, we explained why imitation grape flavor might taste weird to you, or you could learn more about why food might taste better if you had a meal while facing a mirror.