What Einstein Kept Under His Hat: Secrets of Science in the Kitchen (7 page)

Ingested alcohol is absorbed uniformly into all water in the body; about 80 percent of the absorption takes place in the stomach and 20 percent in the small intestine. The BAC will therefore depend on how much water a person’s body contains: the more of that water is in the form of blood, the lower the concentration of a given amount of alcohol and the lesser the physiological effects. Again, everybody’s different, but on average, males are 58 percent water by weight and females are 49 percent, while blood is 80.6 percent water in both men and women.

Engaging in a bit of calculator calisthenics using these numbers and the fact that the density of blood is 1.06 grams per milliliter, I find that for each 10 grams of pure alcohol absorbed by a 170-pound male, his BAC will go up by 0.019. For a 120-pound female, ten grams of pure alcohol will raise her BAC by 0.032. That means that to reach the legal BAC of 0.080 for a DUI citation, a 170-pound male need drink 42 grams of pure alcohol and a 120-pound female need drink only 25 grams.

In round numbers, that translates to (name your poison):

• 80-proof spirits (40 percent alcohol):
5 ounces for a 170-pound male and 3 ounces for a 120-pound female.

• Wine (at 13 percent alcohol):
14 ounces for a 170-pound male and 8 ounces for a 120-pound female.

• Beer (at 5 percent alcohol):
37 ounces for a 170-pound male and 22 ounces for a 120-pound female.

These estimates are very rough, not only because people differ so much but because the calculations assume prompt and complete absorption of the alcohol, without accounting for delayed absorption caused by eating while drinking, or for the liver’s continuous processing of the alcohol, or for the elimination of alcohol in urine over the course of the party. It’s all a rather complex input/output system. Nevertheless, for a very conservative, ballpark estimate, keep track of the number of ounces you consume, and take the amounts above, adjusted for body weight and food consumption, as your probable “drunk threshold.”

Of course, you’ll want to stop long before that. But admittedly it’s hard to count ounces while singing “Auld Lang Syne” with a lampshade on your head. What you can do, however, whether you’re male or female, big or small, a heavy or “social” drinker, is this: Every half-hour on the dot, conjure up a virtual out-of-body experience and observe your own behavior from an objective distance. The moment you see or hear yourself entering stage 2, or at most stage 3, cut yourself off at the bar, eat more food, and go home with your reputation intact.

I have heard about all sorts of treatments for removing red wine stains from tablecloths and clothing. The things I hear about most often are club soda and salt, but I’ve tried both without success. There must be a way that really works. Do you know it?

....

U
pon learning that I have a Ph.D. in chemistry, innumerable acquaintances have asked my expert advice on profound scientific questions such as yours. (For this I spent twenty years in school?)

But okay. I hereby abandon my role of writing about the food and drink that go into our mouths in favor of addressing what misses our mouths and winds up in parts unintended.

The moment a klutzy guest upsets a glass of red wine onto the hostess’s tablecloth, there inevitably arises a chorus of cries from all assembled: “Get some club soda!” “Pour white wine on it!” “Get vinegar!” “Cover it with salt!” All well-meaning but useless. As far as salt is concerned, its only value is to soak up the excess liquid by capillary action, which sand would accomplish just as well. But there shouldn’t be any excess liquid anyway if you have blotted the stain immediately, an essential first step in treating any stain.

As for the three touted liquids—club soda, white wine, and vinegar—the irony is that they are all acidic and may actually intensify the stain. Here’s why.

The pigments in grape skins, belonging to a family of food coloring chemicals known as anthocyanins, behave as acid-base indicators (see p. 13). That is, they are red in acidic media and pale purple in alkaline media. Adding an acidic liquid to the already acidic wine stain does nothing except perhaps to dilute the stain, which plain water would do.

I have always been suspicious of the club soda remedy, which is touted more highly than any other. I just couldn’t see any chemical reason for it to work, so I decided to test it. (The trouble with this world is that people go around telling other people what works for this or that, without anyone ever doing a careful experiment to see if it’s true.)

First, I treated a fresh wine stain on white cotton with plain carbonated water, or seltzer, known to chemists as carbonic acid. Being acidic, it did nothing to diminish the red color of the wine stain.

Then I tried the legendary club soda, which is carbonated water with a small amount of added sodium bicarbonate (baking soda) and in some cases also a small amount of sodium citrate. Both of these chemicals reduce the acidity, but I found that the club soda was still slightly acidic and didn’t change the red color. It did zilch. So much for the many members of the Club Soda Club.

Well, what does work? A few years ago, researchers at the University of California, Davis—professor of enology (wine chemistry) Andrew L. Waterhouse and his student Natalie Ramirez—tested a variety of formulations, both commercial and homemade. Several commercial “wine stain remover” products failed miserably. But depending on the type of fabric and the age of the stain, generally good results were obtained with a 50–50 mixture of 3 percent hydrogen peroxide and a certain brand of liquid dishwashing detergent.

There is no need to mix up such a concoction and keep it around for emergencies; it doesn’t keep well anyway. But the hydrogen peroxide in the Davis tests gave me an important clue, because peroxides are bleaches, although much less potent than chlorine bleach, which might remove not only the stain but all the color in the fabric as well. Peroxides are what the detergent makers call “color-safe bleaches.” They oxidize the colored chemicals to colorless forms.

I decided to test several new products containing sodium percarbonate, a so-called addition product of sodium carbonate (washing soda) with hydrogen peroxide, which have come onto the market since the Davis experiments were done. I found that they work miraculously well on red wine stains.

I tested three of the percarbonate products that were available in my supermarket: Oxi Clean, Clorox Oxygen Action, and Shout Oxy Power. I sprinkled them (they’re all white powders) on wine-stained white cotton, sprayed them liberally with water to wet the powders and let them sit for about ten minutes.

As I watched, the highly alkaline sodium carbonate turned the stains blue, and then the hydrogen peroxide took over and bleached the blue color out almost completely. (Shout Oxy Power worked somewhat faster than the others.) I then threw the fabrics into the washing machine, percarbonate and all, and washed them with detergent. Not a trace of stain was left in any of them!

So check the ingredient labels on cleaning products in the supermarket. If you see “sodium percarbonate,” buy it and keep it handy. It’s good for many other stain-removal jobs.

Save the club soda for your scotch.

A craven disclaimer: Stain removal can be challenging and not always predictable, depending on the exact nature of the staining substance, the age of the stain, and the type and color of the fabric. My tests were done on fresh merlot stains on plain white cotton. Never use any stain-removal technique—including the one above—without first testing it on an inconspicuous part of the tablecloth or garment.

Chapter Two

Down on
the Farm

....

T
HE FARM IS
where it all begins. The earth. The land. The soil.

Some nine thousand years ago, when we humans began to supplement our hunting-and-gathering existence with animal domestication and agriculture, we planted the seeds (to use a fitting metaphor) of modern farming. Although we still hunt and gather on the seas (see Chapter 6), the main source of virtually all human food is agriculture, farming the Good Earth to raise both crop and stock.

There are many kinds of farms. The greatest number by far raise grain (see Chapter 5), such as the rice, corn, and wheat that sustain nearly all of the world’s population. Others grow fruits (Chapter 4) and members of the catchall category we call vegetables (Chapter 3). Still others raise livestock for their meat (Chapter 7), their milk, or their eggs.

This chapter focuses on the last two: the products of dairy farms. There, the two fundamentals of animal existence, the life-initiating egg and the life-sustaining milk of mammals, are obtained from domesticated animals. We either consume them as is or transform them mechanically, chemically, or biologically into products such as butter and cheese and then incorporate them into hundreds of dishes throughout the world’s cuisines.

You will not find here the answer to a mystery that has haunted me for years, because I haven’t been able to find an answer: Why do we speak of dairy and eggs as if there were an obvious connection between them, as there is between fruits and vegetables or between meat and fish? A quick glance at the animals involved should convince even the most casual observer that cows and chickens really have little in common. The farmer has yet to be born who goes out in the morning to collect cow’s eggs and to milk the chickens.

Nevertheless, I shall perpetuate the “dairy and egg” association by treating them both within the same chapter.

I always used skim milk until recently, when fat-free milk became more available. I didn’t like the fat-free milk as much, however, and my visiting grandson wouldn’t touch it. So I bought some low-fat milk. That made me wonder: What’s the difference between these products? True skim milk was blue-white, and the edge around the glass was translucent. Why can’t I have my good old skim milk back again?

....

W
hen a billboard asks, “Got milk?,” we may be tempted to reply, “Can you be more specific, please? Are you asking about raw milk, pasteurized milk, homogenized milk, aseptically packaged milk, whole milk, skim milk, 2 percent milk, 1 percent milk, fat-free milk, evaporated milk, condensed milk, or buttermilk?”

If cows ever knew how we humans monkey around with their God-given, natural product, they’d jump over the moon.

But first, do you think you know what milk
is
? According to the U.S. Code of Federal Regulations, Title 21, Volume 8, Chapter I, Part 1240, Subpart A, Section 1240.3(j), Release 13, milk is “the lacteal secretion obtained from one or more healthy milk-producing animals, e.g., cows, goats, sheep, and water buffalo, including, but not limited to, the following: lowfat milk, skim milk, cream, half and half, dry milk, nonfat dry milk, dry cream, condensed or concentrated milk products, cultured or acidified milk or milk products . . .” and on and on for eighty-eight more words.

(Bureaucracy? What bureaucracy?)

Now that we know what we’re talking about—always a good idea—let’s first tackle the fat problem. I’ll stick to the “lacteal secretion” of cows (genus
Bos
) only, assuming that you know what they are without the help of a zoologist or the U.S. Code of Federal Regulations.

Our contemporary American society appears to have concluded that the 8 grams of fat in an 8-ounce glass of typical whole milk constitutes a serious threat to our survival as a civilization. Hence, our markets offer us a dizzying variety of milks with ever-diminishing fat contents.

In simpler times, one could obtain “skimmed milk” or “skim milk” by allowing most of the fat globules to rise to the top of a bottle of whole, un-homogenized milk and skimming off what we called “the cream,” as if milk and cream were two distinct products with nothing in between. But today, both milk and cream come in a variety of fat contents.

Our supermarkets’ dairy sections offer us a confusin’ profusion of choices—a broad spectrum of fat contents in milk products produced, according to the U.S. Code of Federal Regulations, Title 21, Volume 8, etc., etc., “by modifying the chemical or physical characteristics of milk, cream, or whey by using enzymes, solvents, heat, pressure, cooling, vacuum, genetic engineering, fractionation, or other similar processes, [or] by the addition or subtraction of milk fat or the addition of safe and suitable optional ingredients for the protein, vitamin, or mineral fortification of the product.” But you knew all that, right?

So what’s a consumer to do?

Fortunately, what the dairy industry hath given, the government hath taken away. The U.S. Food and Drug Administration (FDA) has lumped the fat contents of milk and cream into only four categories of milk and six of cream, including two sour creams. Table 1 lists these products by the label names the FDA permits the manufacturers to use, as of a January 1998 regulation. The corresponding traditional names are shown in parentheses.

The numbers of fat grams and calories shown in the table are taken from the USDA’s Nutrient Database for Standard Reference, a compilation of the average compositions of virtually all foods. Individual brands, however, will vary somewhat.

Note that even though there are 9 calories in a gram of fat, the number of calories in a given milk product is not necessarily nine times its number of grams of fat; there are calories also in its proteins and carbohydrates. Also, because the various kinds of milk differ in more ways than fat content, the number of calories per cup won’t necessarily be additive or subtractive in line with the amount of fat.

From the table we see that eliminating virtually all the fat from whole milk reduces the number of calories per cup only from 149 to 86, saving you a mere 63 calories. On the other hand, substituting a cup of one kind of cream for another can make as much as a 500-calorie difference.

One cup of heavy whipping cream, incidentally, makes two cups of whipped cream, halving one’s guilt-by-volume. The second cup is pure, no-calorie air.

We perpetrate even greater crimes on milk than relieving it of its fat-induced richness. For example, we remove about 60 percent of the water from whole milk, put it in cans, and call it evaporated milk (19.1 grams of fat and 338 calories per cup). All of the milk’s fat is retained, except in the inevitable low-fat and no-fat versions of evaporated milk. For example, evaporated skimmed milk (or is it skimmed evaporated milk?) contains 0.5 gram of fat and 200 calories per cup. Sweetened condensed milk (26.6 grams of fat and 982 calories per cup) is evaporated milk mixed with about 45 percent sugar.

And so it goes. Your precious skim milk still exists, albeit hidden behind any one of several modern aliases.

LA CRÈME DE LA CRÈME

What’s the difference between all the kinds of cream I see in my grocer’s dairy case: heavy cream, whipping cream, light cream, half-and-half, etc.?

....

C
ream is made from milk by boosting the percentage of milk fat (also called butterfat, because it is made into butter) beyond the percentage the cow put into it. That is, some of the watery, non-fatty part of the original milk (the “skim milk”) is removed to increase its “richness”: its smooth, unctuous mouth feel.

How? Well, gravity will do the job automatically if one lets whole, un-homogenized milk stand for a while. Since fat is lighter (less dense) than water, it will float to the top, and the fat-rich portion—the cream—can be poured off.

But dairies separate the globules of fat much more quickly and efficiently from the rest of the milk by using centrifuges or so-called cream separators—machines that spin the whole milk around at thousands of revolutions per minute as if it were laundry in the spin cycle of a washing machine gone berserk. The heavier (more dense), watery skim is forced outward more strongly than the fat and migrates toward the outer portions of the bowl-shaped container, while the less dense fat globules linger nearer the center. A stack of conical vanes collects products of various densities, that is, products with various percentages of fat.

The U.S. Department of Agriculture (USDA) regulates the labeling of creams of various fat contents. Heavy cream, sometimes called heavy whipping cream, is literally the
crème de la crème
, because it contains the highest percentage of butterfat: from 36 to 40 percent. Lighter whipping creams may contain from 30 to 36 percent butterfat, but anything less than 30 percent won’t whip. Light cream, sometimes called coffee cream, contains 18 to 30 percent butterfat.

Half-and-half is supposedly half milk and half cream, but that’s not to be taken literally; its butterfat content depends on how heavy or light the “cream” half is. Half-and-half can run from 10.5 to 18 percent butterfat.

Because the label wordings can still vary within the USDA regulations, just select your cream in the market by looking at the fat content printed on the container.

A small, hand-cranked cream separator. The cream comes out of one spout (at left) and the milk comes out of the other.
(Courtesy Hoegger Goat Supply.)