What Einstein Told His Cook (13 page)

In addition to its tartness, citric and other acids retard the browning of fruits by enzymes and oxidation. It is obtained from citrus fruits or fermented molasses and is used in Middle Eastern and Eastern European dishes, commonly in borscht. You can find it by the name
sour salt
in kosher markets or in the ethnic foods section of the larger supermarkets, or as
lemon salt
in Middle Eastern markets.

Citric acid is not alone in its sourness, by any means. All acids are sour. In fact,
only
acids are sour, because of their unique property of producing so-called hydrogen ions, which make our taste buds shriek “sour” to our brains. The strongest acids in your kitchen are vinegar and lemon juice. But sour salt, being 100 percent citric acid in crystalline form, is much more sour than vinegar, which is only a 5 percent solution of acetic acid in water, or lemon juice, which contains only about 7 percent citric acid.

Citric acid is unique in that it contributes sourness virtually without any other flavor, whereas the assertive flavors of lemon juice and vinegar must be factored into the overall balance of any dish. American chefs could well benefit by experimenting with sour salt in dishes that need a touch of tartness without any accompanying lemony or vinegary flavors.

A BAD RAP FOR THE TARTARS

What is cream of tartar? Is it related to tartar sauce or steak tartare?

N
ot at all. The words
tartar
and
tartare
come to us from two different directions.

“Tartar” or “Tatar” was the Persian name for Genghis Khan’s horde of Mongols who stormed through Asia and Eastern Europe in the Middle Ages. The Tartars were viewed by Europeans as being, shall we say, culturally challenged, or at the very least politically incorrect, inasmuch as they wore the whole skins of animals and often ate their meat raw. One of our contemporary, semi-barbaric delicacies was therefore given the name steak tartare: ground or minced raw beefsteak mixed with chopped raw onion, raw egg yolk, and salt and pepper, with
ad lib
touches of Tabasco, Worcestershire, Dijon mustard, anchovies and capers. (James Beard ventured to civilize his with cognac.)

Tartar sauce is mayonnaise with chopped pickles, olives, chives, capers, and such mixed in. It is traditionally served with fried fish. Classic tartar sauce may contain vinegar, white wine, mustard, and herbs, so it may have been dubbed “tartar” because of its potency and pungency. In fact, the French refer to a variety of highly seasoned dishes as
à la tartare
. The Tartars apparently take the rap for almost anything that’s raw, pungent, or crude.

The “tartar” in cream of tartar is quite another story. It comes to us via old Latin from the Arabic
durd
, meaning the dregs or sediment that form in a cask of fermenting wine. Today’s winemakers use the word
tartar
specifically for the brownish-red, crystalline deposits left in the bottoms of casks after the wine has been drawn off. Chemically, it is impure potassium hydrogen tartrate (aka potassium bitartrate or potassium acid tartrate), a salt of tartaric acid. “Cream of tartar” is the fancy name given to the white, highly purified potassium hydrogen tartrate that’s sold in food stores.

The tartar that forms in wine casks comes from the tartaric acid present in grape juice. Tartaric acid is what gives wine about half of its total acidity. (Malic acid and citric acid contribute most of the rest.) The salt called tartar was known long before its parent acid was discovered, and when tartaric acid was ultimately nailed down by chemists they named it after the tartar in the wine casks. It’s a case of the parent chemical being named after its offspring.

The most common use for cream of tartar in the kitchen is for stabilizing beaten egg whites. It accomplishes this trick because it is somewhat acidic, even though it is a salt. (Techspeak: It lowers the pH of the mixture.) A stable egg-white foam depends on the coagulation of its several kinds of proteins, among which the best foam producers are known as globulins. The right acid conditions make the globulin proteins lose their mutually repulsive electric charges, thus making it easier for them to coagulate in the bubbles’ walls and make them stronger, like balloons made of stronger rubber.

Quite a few books mistakenly state that cream of tartar is tartaric acid instead of its salt, potassium hydrogen tartrate. That’s an easy error to make because, as I’ve said, cream of tartar is slightly acid even though it is a salt.

JEKYLL AND HYDE IN A BOTTLE

Why does vanilla extract smell so good and make food taste so good, yet taste so awful from the bottle?

V
anilla extract is around 35 percent ethyl alcohol, which has a harsh, biting flavor. Whiskeys and other distilled beverages contain even more alcohol, of course (usually 40 percent), but they are lovingly produced by time-honored flavoring and aging processes that soften the harshness.

“Pure vanilla extract,” in order to be labeled as such, must be extracted from real vanilla beans. But the chemical that gives the beans most of their great flavor and aroma is vanillin, and chemists can make vanillin a lot more cheaply than the vanilla plant (an orchid) can. Synthetic vanillin is used commercially to flavor baked goods, candies, ice creams, and such. It’s identical to the natural chemical, and is the main ingredient in imitation vanilla flavoring.

Real vanilla extract is so much more complex than just plain vanillin, however, that it doesn’t pay to buy the imitation stuff, especially since you use so little of it and it keeps forever. More than 130 distinct chemical compounds have been identified in true vanilla extract.

Even better for some applications is a whole vanilla bean, obtainable for a few dollars in an airtight glass or plastic test tube. The bean should have a flexible, leathery texture, rather then being dried out and hard. (The vanilla “bean” is not a bean, by the way; it’s a pod. Beans are seeds, whereas pods are fruits that contain seeds.) The vanilla flavor and aroma are mostly concentrated in the pod’s seeds and especially in the oily liquid that surrounds them, so for the most intense flavor as a recipe ingredient, slit the pod lengthwise with a sharp knife and use the seeds, scraping them out with the back of the knife blade.

The pods are also aromatic and flavorful, however, and should not be discarded. Bury them in granulated sugar in a tightly sealed jar for a few weeks, shaking the jar periodically. The sugar becomes infused with the flavor of vanilla and is great in coffee or for flavoring baked goods.

PERCHANCE TO ENHANCE

What is MSG, and does it really “enhance flavors”?

I
t certainly does sound mysterious that these innocent-looking fine, white crystals with no really distinctive taste of their own should be able to boost the inherent flavors of such a wide variety of foods. The mystery lies not in whether MSG really works—nobody doubts that—but in
how
it works. As is the case with so many ancient, stumbled-upon practices, a lack of scientific understanding hasn’t stopped people from enjoying the benefits of MSG for more than two thousand years.

What makes MSG’s reputation as a flavor enhancer so hard to swallow is that the terminology is somewhat misleading. Flavor enhancers don’t enhance the flavors of foods in the sense of improving them; that is, they don’t necessarily make things taste better. What they seem to be doing is intensifying, or magnifying, certain flavors that are already present. The food processing industry likes to call them potentiators; I call them flavor boosters.

At this point, I’m obliged to acknowledge the debate about its effects on sensitive individuals.

Everyone has heard of Chinese Restaurant Syndrome or CRS, an unfortunate and politically incorrect label that was applied in 1968 to a diffuse collection of symptoms, including headaches and burning sensations, reported by some people after consuming their selections from column A and column B. The culprit behind CRS appeared to be MSG, which is short for its chemical name, monosodium glutamate (gluTAMate). And thus began a thirty-year battle over its safety.

In one corner sits the National Organization Mobilized to Stop Glutamate, whose uncomplicated solution to the problem is expressed in its acronym. According to NOMSG, glutamates in their many guises (see below) are responsible for at least twenty-three afflictions, from runny noses and bags under the eyes to panic attacks and partial paralysis.

In the other three corners, predictably, are the manufacturers of prepared foods, who find MSG and similar compounds to be enormously valuable in enhancing the consumer appeal of their products.

The official referee is the FDA who, after many years of evaluating data, remains convinced that “MSG and related substances are safe food ingredients for most people when eaten at customary levels.” The trouble is that all people are not “most people,” and the FDA is still struggling to regulate the labeling of glutamate-containing foods so as to be most useful to all consumers.

Monosodium glutamate was first isolated from kombu seaweed by a Japanese chemist in 1908. The Japanese call it
aji-no-moto
, which means “essence of taste” or “at the origin of flavor.” Today, 200,000 tons of pure MSG is produced every year in fifteen countries. It is sold by the carload to manufacturers of prepared foods and by the ounce to consumers as Ac’cent and Zest.

Monosodium glutamate is a salt of glutamic acid, one of the most common amino acids that proteins are made of. The flavor-boosting properties reside in the glutamate part of the molecule, so any compound that releases free glutamate can perform the same trick. The monosodium version is merely the most concentrated and convenient form of glutamate.

Parmesan cheese, tomatoes, mushrooms, and seaweed are rich sources of free glutamate. That’s why a little bit of any of these ingredients can give a big boost to the flavor of a dish. The Japanese have traditionally made use of seaweed’s glutamate in subtle, delicate soups.

Our sense of taste involves some very complex chemical and physiological reactions. Exactly how glutamates fit in has been hard to pin down. But there are a couple of ideas that have been kicking around.

It is known that different-tasting flavor molecules stick to the receptors in our taste buds for different lengths of time before detaching. One possibility, then, is that glutamates make certain molecules stick around longer, and therefore taste stronger. Also, it is probable that glutamates have their own distinct set of taste receptors, separate from the receptors for the traditionally quoted quartet of sweet, sour, salty, and bitter. To further complicate matters, quite a few substances other than glutamates have “flavor enhancing” properties.