Ah, the first new Good Eats of the season (Fall that is, Good Eats seasons start in the summer technically). This is the 3rd show Alton has done dedicated to deep frying. In this episode, he shows the viewer how to make tempura. Tempura has its origins in Japan. It is basically battered coated deep fried vegetables and/or seafood. A liquid batter is used, not a dry batter like bread crumbs or corn flakes. Alton said that although simple sounding, cooks are intimidated by tempura. It is something that is easy to make, but can be hard to make well. Alton provides 3 steps to making good tempura.
1. The food must be prepped perfectly
Alton suggests a high surface to mass ratio for the foods, so they cook quickly. He likes to use green beans, flat leaf parsley, shrimp, Tilapia, and sweet potatoes in his tempura.
2. The oil must be the right temperature
To fry the tempura, Alton chooses the Cast Iron Dutch Oven as his vessel of choice. They are cheap and versatile. I use my Lodge Dutch Oven all the time. He does not recommend using an electric deep fryer, because they are hard to clean and do not maintain temperatures well enough. Make sure to use a deep fry thermometer to help maintain 375 degrees (adjust your burner up and down to help maintain temperature). As for the oil of choice, he uses vegetable oil. You just need an oil that has no flavor of it's own and has a high smoke point. Canola oil would probably be the one I would use here.
3. The batter must be light, crisp, flavorful, but not greasy
The typical batter is simply water, wheat flour, and 1 egg. The problem with this is gluten. What is good for yeasty breads is not so good for tempura. In order to get a nice light, crisp, flavorful, and not greasy batter you need to limit the production of gluten. Alton does this by trading out all-purpose flour for low protein cake flour and some rice flour. Less protein, less gluten. He also substitutes the water for club soda and vodka. The club soda adds bubbles which aerates the mixture, making a lighter batter. Those with aversions to alcohol could just go with the club soda.
I had never heard of tempura before so this was a very informative episode. The best thing I got out of it was an idea to change my favorite fried cod recipe. I am going to try using lower protein flour and club soda in my recipe in order to make a light more crisp batter. That is what I like about Alton Brown, he can inspire the way you cook, not just what you cook. If he didn't explain why he changed his liquid and flour type, then I wouldn't have been inspired to alter my cod recipe. Thanks Alton!