What’s a Great Way to Get a Fish Fried? Give It a Shot of Vodka

FRYING fish is not exactly a new idea, but people do come up with new ways to do it. Some are more practical than others. At last year’s Madrid Fusión, the annual gathering of the world’s restaurant avant-garde, the Spanish chef Dani García demonstrated a method that couldn’t have been simpler:

Take a small whole turbot untouched by a knife, dredge it in a mixture of bread crumbs and flour, and drop it directly into hot oil. The skin puffs out away from the body, insulating the interior from the high heat, so you get an ideal result: moist, tender flesh and crisp, flavorful skin.

There is one small problem. The technique works only if the skin is perfectly intact. The slightest nick quickly turns into a major breach, oil pours through, and the fish ends up overcooked and sodden. Which is what usually happens. Despite his access to pristine fish, Mr. García estimated his success rate at around 10 percent.

A more reliable innovation comes from Heston Blumenthal, chef at the Fat Duck near London.

Mr. Blumenthal recently undertook a series for BBC Two television and a book, both called “In Search of Perfection,” in which he updated classic British foods. His beer batter for fish and chips, developed with the Fat Duck’s research manager, Christopher Young, is unusual in two ways. It’s squirted as a foam from a soda siphon — the sure sign of a post-Ferran Adrià preparation — and half of its liquid is vodka. The siphon makes things easier if you have more than a few batches to fry, but even without a siphon the vodka is an excellent trick.

Batter creates an artificial skin around the food being fried, a skin made of flour and just enough liquid to hold the flour and spread it out. The batter clings to the fish, insulating it from the direct heat of the oil and transmitting a more moderate heat, so the flesh cooks gently without becoming dry and fibrous. (The batter dries out in its place.)

The oil temperature for frying is well above the boiling point of water, so it vaporizes the water in the batter — hence all the bubbling — and creates a dry, crunchy, golden, flavorful crust. But crusts can also end up tough and chewy, or weak and crumbly.

Toughness develops when the proteins in wheat flour have a chance to form the elastic gluten network that’s great in a bread, but not as the container for a moist, tender morsel of fish. A powdery crust results if there’s too little gluten — or some other protein, like egg — to hold the flour’s starch particles together. Air bubbles in the batter make the crust lighter and more delicate, which is why some recipes call for whipped egg whites, baking powder or yeast.

The Fat Duck’s batter is made with all-purpose flour, as well as some rice flour, whose proteins don’t form an elastic gluten, and baking powder. The liquid is half beer and half vodka. The ingredients are mixed, then charged with carbon dioxide in a soda siphon and refrigerated.

The siphon keeps the batter fully carbonated, to be dispensed fresh and bubbly as needed, and produces a very porous coating that’s especially crunchy — with each bite you crush many thin layers of crust. But I usually dispense with the siphon and settle for the bubbles produced by the beer and the baking powder during the frying.

The key to the Fat Duck batter is the alcohol, which does a couple of very useful things. It dissolves some of the gluten proteins in the wheat flour, so no elastic network forms and the crust doesn’t get tough. (You’ll notice when you combine the ingredients that the mix becomes mushy rather than sticky.) Alcohol also reduces the amount of water that the starch granules can absorb, and boils off faster than water, so the batter dries out, crisps and browns quickly, before the delicate fish inside overcooks. The crispness lasts through the meal, and revives well the next day in a hot oven.

The batter proportions aren’t crucial. I’ve found that rice flours vary in coarseness, with stone-ground brands producing a rough crust compared with the finer Japanese-style “sweet” rice flour. (It’s used to make sweets, but doesn’t taste sweet.) When frying oysters, I like to replace some of the rice and wheat flours with buckwheat, even though it shades the crust toward a dark gray with gold highlights.

The batter thickens with time as the starch absorbs moisture, so adjust it as you go to the consistency of pancake batter, with more beer, vodka or both.

Even with nicked fish you’ll bat close to a thousand.

March 7, 2007

Copyright 2007 The New York Times Company