Marlene Parrish - What Einstein Told His Cook 2

IT’S BITTER BEING GREEN

At times, I find a cucumber that is bitter. Why?

Does the compound that causes the bitterness have any health implications? Could it be dangerous?

Cucumbers have been cultivated for thousands of years, and like many food plants, they have been improved by cross-breeding to accentuate the better and eliminate the bitter.

Old recipes often include a de-bittering step, such as soaking the slices in salt water. (I doubt that that works anyway.) But modern varieties are rarely bitter except in the skin, which can be peeled off.

Part of the flavor of cucumbers is due to slightly bitter compounds called cucurbitacins. But when a cucumber has had a hard life back on the plant, such as a long spell of hot, dry weather or a battle with insects or disease, the amount of cucurbitacins builds up defensively in the flesh as well as in the skin. The bitterness is Nature’s way of saying, “Don’t eat me or you’ll be sorry.” Alkaloids, for example, a class of mostly toxic chemicals found in plants, all have a bitter taste. But the amount of cucurbitacin you’re likely to find in a cucumber certainly won’t kill you. If you come upon a bitter cuke, chalk it up to the luck of the draw and move on to some others that may have had a less stressful youth back on the farm.

Today’s rarely bitter cucumbers are often sliced and salted, not to remove bitterness but to crisp them up. Sprinkle salt on sliced cucumbers in a bowl, top them with a layer of ice cubes, and put them in the refrigerator for an hour or so. The salt will draw water from between the fruit’s cells, firming up their structure. Wash the excess salt off before using.

While a coating of solid salt will draw water out of cucumber slices and crisp them, soaking them in salt water has the opposite effect: they will soak up water and become softer, or wilted. That’s because osmosis draws water from a less salty environment into a saltier one. When the cucumber cells are in contact with solid salt, some of its water will be drawn out. But when they are in contact with a rather dilute salt solution, some of the solution’s water will be drawn into the cells. (For further details, see “Osmosis,” chapter 4.)

Cucumber skins aren’t completely impermeable to moisture, so the fruit will eventually dry out and shrivel if not protected by a moisture-proof coating. Cuke moguls therefore spray their product with an FDA-approved, edible wax to prolong their produce-counter lifetimes. The smaller, warty-skinned pickling cucumbers are not waxed because in pickling it is essential that the pickling liquor penetrate the vegetable. So-called English cucumbers, being long and thin with consequently large surface areas, must be protected by more than a wax coating and are usually wrapped in plastic film.

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SPILLED MILK

What is it about soy milk that makes it boil over?

One of my recipes requires cooking the soy milk.

I found I was able to accomplish this without having it boil over as long as I only simmered it.

What is the chemistry behind this?

Ihave often wondered how they milk those little soybeans, haven’t you?

Sorry. Soy milk is made by soaking, boiling, grinding, and pressing the liquid out of soybeans. The liquid is called “milk” because it is white, but it bears as little relationship to cow’s milk as does milk of magnesia.

Soy milk is a tempting alternative to cow’s milk because it is higher in protein, lower in fat (and calcium), and free of cholesterol and lactose, which millions of lactose-intolerant people are incapable of digesting properly. When fortified with calcium and vitamins, it can be used as infant formula for the estimated 7 percent of babies in the United States who cannot digest cow’s milk.

Nevertheless, soy milk is far from a substitute for natural milk, either in flavor or in many culinary applications. For one thing, the soybean-crushing process releases an enzyme, lipoxygenase, that catalyzes the oxidation of the beans’ unsaturated fatty acids into unpleasant-tasting compounds. While that doesn’t seem to bother Asian consumers, the enzyme must be deactivated for most Western palates by heating the “milk” to a temperature near its boiling point for 15 to 20 minutes.

Which takes us back to the stove.

Plants contain various sugar-related chemicals called glycosides that serve a wide range of functions. Some of the glycosides in soybeans are called saponins (from the Latin sapo , meaning soap) because they foam up into suds when boiled. They are the source of your boiling-over problem. But heat destroys the saponins, so a period of gentle heating will slowly eliminate the foaming tendency. That’s why you can get away with simmering soy milk but not with boiling it, unless you simmer it first.

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Not-Very-Indian Pudding

Imagine soft polenta that tastes like gingerbread. That’s Indian pudding.

The eighteenth-century New England colonists referred to the New World’s maize as “Indian corn,” and a pudding containing cornmeal eventually became known as Indian pudding. Of course, Native Americans didn’t have soybeans, and neither did the colonists, but vanilla soy milk is an effective stand-in for the milk used in recipes for one kind of Indian pudding.

When ice cream is melted and stirred into the pudding, it is just as good as, and maybe better than, the milk or light cream that is usually called for in recipes for Indian pudding. The recipe is also delicious made with cow’s milk and cow’s-milk ice cream. The leftover pudding will thicken overnight, and it is delicious cold or hot. Try it for breakfast.

4 cups (1 quart) vanilla soy milk

1/3 cup yellow cornmeal

1 tablespoon unsalted butter

½ cup dark molasses

1 teaspoon ground cinnamon

½ teaspoon ground ginger

½ teaspoon salt

½ cup vanilla soy ice cream, melted

Vanilla soy ice cream for serving

1.Place a rack in the lower part of the oven. Preheat the oven to 300°F. In a small bowl, mix 1 cup of the soy milk with the cornmeal. Let stand.

2.In a medium saucepan, slowly heat 2 cups of the soy milk over medium-high heat until bubbles form around the edge of the pan. Gradually stir the cornmeal mixture into the hot soy milk. Reduce the heat to medium and cook, stirring, for 10 minutes. The mixture will be thin.

3.Add the remaining 1 cup soy milk and the butter, molasses, cinnamon, ginger, and salt, and stir just until the butter is melted. The mixture will be thin.

4.Turn the pudding into an ungreased 1½-quart casserole. Bake, uncovered, for 2 hours. The pudding will have a slightly dark film on the top.

5.Remove the pudding from the oven. Stir in the melted ice cream, combining it thoroughly until the pudding is smooth. Return the pudding to the oven and bake, uncovered, for 30 minutes longer.

6.Let the pudding cool on a wire rack for 2 hours. It will thicken as it cools, and a light skin will form. Just before serving, stir in the skin, then spoon the pudding into dessert dishes and serve slightly warm with a scoop of vanilla soy ice cream.

MAKES 8 OR MORE SERVINGS

ODE TO TOFU

There seem to be a dozen forms of tofu in my supermarket. I know that tofu is made from soybeans, but how do they make so many kinds?