What Einstein Told His Cook (3 page)

My point is this: In raw cane juice you have a mixture of sucrose plus all the other components of cane that end up in the molasses. When the molasses components are removed, will someone please explain to me how the remaining pure sucrose suddenly becomes evil and unhealthful? When we eat the more “healthful,” browner sugars, we’re eating just as much sucrose along with the molasses residues. Why isn’t the sucrose evil in that form?

A SUPERFINE GLASS OF TEA

To sweeten my iced tea quickly, I added powdered sugar. But it turned into gummy lumps. What happened?

G
ood try, but you used the wrong sugar.

Ordinary table sugar is “granulated,” meaning that it consists of individual granules or grains, each of which is a single crystal of pure sucrose. But when pulverized into a fine powder, sugar tends to pick up moisture from the air and cake. (Techspeak: sugar is hygroscopic.) To prevent this, the manufacturers of powdered sugar add about 3 percent of cornstarch. It’s the starch that gummed up your tea, because it won’t dissolve in cold water.

What you should have used is superfine or ultrafine sugar, which is not a powder in the strict sense. It consists of tinier crystals than those in ordinary granulated sugar, and it therefore dissolves more easily. It’s used by bartenders because it dissolves quickly in cold mixed drinks and by bakers (it’s sometimes called baker’s sugar) because it blends and melts faster than ordinary granulated sugar.

ROCK SALT SÍ, ROCK SUGAR NO!

My brown sugar has turned into rock. What can I do to soften it?

T
hat depends on whether you need to use it right away. There’s a quick fix that gives temporary results—long enough for you to measure some out for a recipe—and there’s a more time-consuming but longer-lasting fix that will restore your sugar to its original, manageable form.

But first, what makes brown sugar turn hard in the first place? Loss of moisture. You didn’t reseal the package tightly enough after opening it, and it dried out to some extent. It’s not your fault; it’s almost impossible to reseal an opened box of brown sugar completely. So after you use some, always repackage the remainder in an airtight (more exactly, a vapor-tight) container such as a screw-top jar or a plastic food storage box with a tight lid.

The brown sugar sold in stores consists of white sugar crystals coated with a thin film of molasses, the thick, dark liquid left behind when sugar-cane juice is evaporated to allow crystals of pure sugar—sucrose—to separate out. Because the molasses coating has a tendency to absorb water vapor, fresh brown sugar is always very soft. But when exposed to dry air, the molasses loses some of its moisture and hardens, cementing the crystals together into lumps. You then have a choice: either restore the lost water or try somehow to soften the hardened molasses.

Restoring the water is easy, but it takes time. Just seal the sugar in a tight container overnight along with something that gives off water vapor. People have recommended everything from a slice of apple, potato, or fresh bread to a damp towel or, for no-nonsense types, a cup of water. The most effective setup is probably to put the sugar in a tight-lidded container, cover it with a sheet of plastic wrap, place a damp paper towel on top of the plastic wrap, and seal it all up. After a day or so when the sugar becomes soft enough, discard the towel and plastic wrap, and reseal the container tightly.

Many food books and magazines inform you that brown sugar hardens because it loses moisture, which is true, and then go on to tell you to heat it in the oven to soften it, as if the oven somehow restores moisture. It doesn’t, of course. What happens is that the heat softens, or thins, the molasses “cement,” which then re-hardens as it cools.

Some brown sugar packages recommend placing the hardened sugar in the microwave oven along with a cup of water. The water isn’t there to hydrate the sugar, though, because in the couple of minutes it takes for the heat to do its job, water vapor from the cup doesn’t have enough time to diffuse through the mass of sugar and hydrate it. The water is there only to absorb some of the microwaves, because microwave ovens shouldn’t be operated in an empty or nearly empty condition (see p. 258). If you’re zapping at least a cup or so of sugar, you probably don’t need the water.

A chef of my acquaintance puts brown sugar out in his restaurant kitchen every day and it dries out rapidly. When it becomes very hard, he puts a few drops of hot water on it and massages it with his hands until it returns to its original texture. That’s fine for the pros, but massaging sugar probably isn’t the average home cook’s idea of fun.

Speaking of molasses, a former Peace Corps volunteer once told me that many years ago in Mhlume, Swaziland, they used to pave dirt roads by spraying them with molasses from the local sugar refinery. It dried out and hardened very quickly, taking a few months to wear back down to the dirt.
(Note to my city’s Public Works Department: Maybe if you used molasses instead of lowest-bidder asphalt, our roads would last longer.)

Finally, if all else fails there is always Domino’s Brownulated or free-flowing sugar, which pours like a dream and never turns into a brick. Domino’s manufacturing trick is to break down some of the sucrose (Techspeak: hydrolyze it) into its two component sugars: glucose, aka dextrose, and fructose, aka levulose. (Some sugars have multiple names.) This mixture, called invert sugar, holds onto water tightly, so hydrolyzed brown sugar granules don’t dry out and cake. Brownulated sugar, however, is intended for sprinkling on oatmeal and such, not for baking, because it doesn’t measure out the same as the ordinary brown sugar that cookbooks specify.

BEET ME WITH A CANE

What’s the difference between cane sugar and beet sugar?

M
ore than half of the sugar produced in the U.S. comes from sugar beets, misshapen, whitish-brown roots that resemble short, fat carrots. Sugar beets grow in temperate climates, such as in Minnesota, North Dakota, and Idaho in the U.S., and in much of Europe, whereas sugar cane is a tropical plant, grown in the U.S. mainly in Louisiana and Florida.

Beet sugar refineries have the more difficult task because the beets contain many bad-tasting and foul-smelling impurities that must be removed. The impurities survive in the molasses, which is inedible and fit only for animal feed. For that reason there’s no such thing as edible brown beet sugar.

Once refined, cane sugar and beet sugar are chemically identical: they’re both pure sucrose and therefore should be indistinguishable from each other. Refineries don’t have to label their sugar as cane or beet, so you may be using beet sugar without knowing it. If it doesn’t say “Pure Cane Sugar” on the package, it’s probably beet.

Nevertheless, some people who have long experience in making jams and marmalades insist that cane and beet sugars don’t behave the same. Alan Davidson, in his encyclopedic
Oxford Companion to Food
(Oxford University Press, 1999), says that this fact “should cause the chemists to reflect, humbly, that they are not omniscient in these matters.”

Touché.

A sugar beet.
Courtesy of the American Sugarbeet Growers Association.

THE CLASSES OF MOLASSES

My grandmother used to talk about sulphured molasses. What is it?

T
he “sulphur” in sulphured molasses is a good starting point for understanding several interesting aspects of food chemistry.

Sulphur is the old-fashioned spelling for sulfur, a yellow chemical element whose common compounds include sulfur dioxide and sulfites. Sulfur dioxide gas is the choking, acrid odor of burning sulfur and is reputed to pollute the atmosphere in Hell, probably because volcanoes belch sulfurous fumes from the nether regions of our planet.

Sulfites release sulfur dioxide gas in the presence of acids, so their action is the same as that of sulfur dioxide itself. Namely, they are bleaching agents and are anti-microbials. Both properties have been used in sugar refining.

Sulfur dioxide has been used to lighten the color of molasses, the dark, sweet byproduct of sugar refining, and to kill its molds and bacteria. The molasses is then said to be sulphured. Virtually all molasses produced today is unsulphured, however. Sulphured molasses is not to be confused with Great-Grandma’s sulphur and molasses, a spring tonic that supposedly “purified the blood” after a hard, cold winter. She mixed a couple of teaspoons of gritty, powdered sulfur into some molasses and fed it to as many children as she could catch. The sulfur is harmless because it isn’t metabolized.

Sulfur dioxide gas is used to bleach cherries white, after which they are dyed a Disneyesque red or green, then flavored with oil of bitter almonds, packed in syrup, and christened
maraschino
, after the liqueur whose flavor these garish creations are striving to imitate.

Sulfites counteract oxidation. (Techspeak: sulfites are reducing agents.) “Oxidation” most commonly refers to the reaction of a substance with oxygen in the air, and it can be quite a destructive process. Witness the rusting of iron—a pure example of what oxidation can do, even to metals. In the kitchen, oxidation is one of the reactions that make fats turn rancid. Assisted by enzymes, oxidation is also what makes sliced potatoes, apples, and peaches turn brown. Dried fruits are therefore often treated with sulfur dioxide to keep that from happening.

But oxidation is a more general chemical process than the simple reaction of a substance with oxygen. To a chemist, oxidation is any reaction in which an electron is snatched away from an atom or molecule. The electron-deprived “snatchee” is said to have been oxidized. In our bodies, such vital molecules as fats, proteins, and even DNA can be oxidized, making them unable to fulfill their critical jobs of carrying on our normal life processes. Electrons are what holds molecules together, and when an electron is snatched away, these “good” molecules can break down into smaller, “bad” molecules.