What Does Marinate Overnight Mean In a Recipe?

I’m with you. Why overnight? Are we to believe that daylight somehow interferes with the marinating process? What if it’s only two o’clock in the afternoon when we arrive at the critical point in the recipe? How early can “overnight” begin? If we do leave it overnight, must we proceed with the recipe the moment … Read more

Why and How Does Brining Make Meat, Poultry, and Fish Juicer?

Brining, soaking meat, fish or poultry in a solution of salt in water, is far from new. Surely, at some time in maritime history, someone discovered, accidentally, perhaps?, that meat that had soaked in seawater was juicier and had better flavor when cooked. How does brining work? What does a bath in salt water accomplish, … Read more

How Is Meat Like Ham and Fish Preserved Without Refrigeration?

Meats don’t spoil because they’re “cured,” which is a catch-all term for any process that inhibits bacterial growth, even at room temperature. But hams can be bewildering. How are they cured? Are all hams salted? Smoked? Do you have to soak them? Cook them? There is no single set of answers to these questions because … Read more

Why Do Bones Make Soup, Stew, and Stock Taste Better By Adding Flavor?

Dem bones are an essential ingredient in making a soup, stock, or stew, every bit as essential as the meat, vegetables, and seasonings. Their purpose may not be obvious, however, if we think of them as hard, nonreactive mineral matter. Yes, their structural material is mineral: calcium phosphates, to be specific. But calcium phosphates don’t … Read more

What Does Prime Beef Mean and Where Does Prime Rib Come From?

USDA Prime is indeed the finest and most expensive grade of beef. But we have all at one time or another been subjected to a $5.95 (salad bar included) slab of tough, dry “prime rib” rimmed with vulcanized-rubber fat that clearly deserved to be stamped “USDA Inedible.” Is there some misrepresentation going on here? Not … Read more

Why Is Ground Beef Dark On the Inside But Bright Red On the Outside?

A freshly cut meat surface isn’t bright red; it’s naturally purplish because it contains the purplish-red muscle protein, myoglobin. But when myoglobin is exposed to oxygen in the air, it quickly turns into bright, cherry-red oxymyoglobin. That’s why only the outer surface of your ground beef is that nice, bright red color that we generally … Read more

People Just Love To Eat Meat and Fish

We humans are an omnivorous lot, with teeth and digestive systems well adapted to eating both plant and animal foods. But animal rights activists notwithstanding, it’s an undeniable fact that in our society, meat and fish are most often the center of the plate, the star players in our main dishes. Of the virtually unlimited … Read more

Why Are Hominy Grits Made With Lye When It’s Corrosive?

Yes, but it has been thoroughly washed out before the grits ever get near your breakfast plate. The word lye is related to the Latin for wash, and originally referred to the strong alkaline solution obtained by soaking, or washing, wood ashes in water. (The alkaline material in wood ashes is potassium carbonate, and because … Read more

How Toxic Are the Eyes of a Potato?

Not as dangerous as some well-meaning friends who spread scary stories. But there is a small grain of truth to the story. When potatoes were introduced into Europe in the second half of the sixteenth century, they were suspected of being either poisonous or aphrodisiac or, an intriguing thought, both. (What a way to die!) … Read more

Why Are Potatoes With Green Skin Toxic and Unsafe To Eat?

It’s not green because it’s unripe; potatoes are ready to eat at any stage of growth. And they’re not flaunting the green because they’re a traditionally Irish food. The green color is Mother Nature’s Mr. Yuk sticker, warning us of poison. Potato plants contain solanine, a bitter-tasting member of the notorious alkaloid family, a group … Read more

Where Does Vinegar Come From and What Is Vinegar Made of?

Vinegar has been known for thousands of years. No one even had to make it in the first place, because it actually makes itself. Wherever there happens to be some sugar or alcohol lying around, vinegar is on the way. Any chemist will tell you without a moment’s hesitation that vinegar is a solution of … Read more

Why Does Lasagne and Spaghetti Eat Holes In Aluminum Foil?

Yup, your lasagne is actually eating holes in the metal. (No reflection on your cooking.) Aluminum is what chemists call an active metal, easily attacked by acids such as the citric and other organic acids in tomatoes. In fact, you shouldn’t cook tomato sauce or other acidic foods in aluminum pots because they can dissolve … Read more

How Does MSG Enhance Flavors In Food and How Is MSG Made?

It 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 … Read more

Why Does Vanilla Make Food Smell and Taste So Good, But Tastes So Awful From the Bottle?

Vanilla 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 … Read more

What Is Sour Salt and Where Does Sour Salt Come From?

Sour salt is misnamed. It has nothing to do with table salt or sodium chloride. In fact, it isn’t a salt at all; it’s an acid. They’re two different classes of chemicals. Every acid is a unique chemical having properties that distinguish it from all other acids. But it can have dozens of derivatives called … Read more

What Is Baking Ammonia and What Is Baking Ammonia Used For?

Ammonia itself is an acrid-smelling gas, usually dissolved in water and used for laundry and cleaning purposes. But baking ammonia is ammonium bicarbonate, a leavening agent that when heated breaks down into three gases: water vapor, carbon dioxide, and ammonia. It isn’t used much anymore , if you can even find it, because the ammonia … Read more

How Does Aluminum Cause Alzheimer’s Disease?

Sodium aluminum sulfate and several other aluminum compounds are listed by the FDA as GRAS: Generally Regarded as Safe. About twenty years ago, one study found increased levels of aluminum in the brains of deceased Alzheimer’s victims. Ever since then, suspicions have been circulating that aluminum, whether in food or water or dissolved from aluminum … Read more

How Is Baking Soda Different From Baking Powder?

It’s all in the chemicals. Baking soda (aka bicarbonate of soda) is a single chemical: pure sodium bicarbonate, whereas baking powder is baking soda combined with one or more acid salts, such as monocalcium phosphate monohydrate, dicalcium phosphate dihydrate, sodium aluminum sulfate, or sodium aluminum phosphate. Now that I’ve warmed the hearts of chemistry fans … Read more

Does Heavy Cream Weigh Less Than Light Cream?

Heavy cream contains a higher percentage of milk fat (usually called butterfat, because butter can be made from it) than light cream does: 36 to 40 percent fat in heavy whipping cream versus only 18 to 30 percent in light cream. And, if you’re interested, the heavy cream can contain up to twice as much … Read more

How Do Those Nonstick Nonfat Cooking Sprays Work?

There is no such thing as a nonfat edible oil. Fats are a family of specific chemical compounds, and an oil is just a liquid fat. Nor do the sprays have to contain a substitute for oil, because, are you ready?, they are oil. Those handy little cans, so great for coating baking pans and … Read more

What Is the Best Way to Dispose of Used Cooking Oil and Fat?

While edible fats and oils are ultimately biodegradable, they can gum up the works in a landfill for years. They’re not as bad as petroleum oils, however, which are digestible by only one or two species of bacteria and stay around essentially forever. Small amounts of fat can be absorbed in a couple of paper … Read more

What Are the Smoke Points of Common Vegetable Oils?

I don’t think you mean boiling point, because in spite of the poetic and sadistic appeal of the expression “boiled in oil,” oil doesn’t boil. Long before it becomes hot enough to think about bubbling, a cooking oil will decompose, breaking down into disagreeable chemicals and carbonized particles that will assault your taste buds with … Read more

How Do They Get Corn Oil Out of Corn?

They use a lot of corn. Corn is indeed a low-fat food, containing about 1 gram per ear until you slather it with all that butter. But it is by far the biggest crop in the United States, grown in 42 states to the tune of more than 9 billion bushels per year. Nine billion … Read more

Why Does European Butter Taste Better Than American Butter?

European butter has more fat. Commercial butter is 80 to 82 percent milk fat (also called butterfat), 16 to 17 percent water, and 1 to 2 percent milk solids (plus about 2 percent salt if salted). The United States Department of Agriculture (USDA) sets the lower limit of butterfat content for American butter at 80 … Read more

What Is Clarified Butter Used For?

Clarifying butter gets rid of everything but that delicious, artery-clogging, highly saturated butterfat. But when we use it in sautéing instead of whole butter, we avoid eating the browned proteins, which could also be unhealthful because of possible carcinogens. Name your poison. Some people think of butter as a block of fat surrounded by guilt. … Read more

How Come the Amounts of Fat on Food Labels Don’t Add Up?

All fats fall into three categories. Saturated, polyunsaturated, and monounsaturated fats. I had never noticed the funny arithmetic you mention, but as soon as I received your question I ran to my pantry and grabbed a box of Nabisco Wheat Thins. Here’s what I saw in the Nutrition Facts panel for the amounts of fat … Read more

Where Does Partially Hydrogenated Vegetable Oil Come From?

Oils are hydrogenated, that is, hydrogen atoms are forced into their molecules under pressure to make them more saturated, because saturated fats are thicker, more solid and less liquid, than unsaturated fats. The hydrogen atoms fill in hydrogen-poor gaps (Techspeak: double bonds, which are more rigid than single bonds) in the oil molecules, and that … Read more

What Makes Fats Turn Rancid?

Free fatty acids. That is, fatty acid molecules that have been broken off from their fat molecules. Most fatty acids are foul-smelling and bad-tasting chemicals, and it doesn’t take much of them to give a fatty food an off flavor. There are two main ways in which the fatty acids can become disconnected: the fat’s … Read more

What Is the Difference Between Fats and Fatty Acids?

Most of us just don’t know the difference between fatty acids and fats. And there is indeed a difference. Every molecule of fat incorporates three molecules of fatty acids. The fatty acids may be either saturated or unsaturated, and they thereby impart those qualities to the fat as a whole. First, let’s see what a … Read more

Why Is Freshly Ground Salt Better Than Granulated Salt?

Freshly ground salt is better for the people who sell those fancy salt mills and combination salt-and-pepper grinders in so-called gourmet shops. The idea seems to be that if freshly ground pepper is so much better than the powdered stuff in cans, then why not use freshly ground salt as well? That’s a delusion. Unlike … Read more

Why Is Kosher Salt Better Than Regular Table Salt?

Kosher salt is misnamed; it should be called koshering salt because it is used in the koshering process, which involves blanketing raw meat or poultry with salt to purify it. Kosher salt may be either mined or taken from the sea; nobody seems to care. Its crystals, however, must always be coarse and irregular, so … Read more

How Is Sea Salt Better Than Regular Table Salt?

The terms sea salt and regular salt or table salt are often used as if they denote two distinctly different substances with distinctly different properties. But it’s not that simple. Salt is indeed obtained from two different sources: underground mines and seawater. But that fact alone doesn’t make them inherently different, any more than water … Read more

How Does Salt Tenderize Meat?

Salt tenderizes meat only to a slight extent. If you read further down the ingredient list of meat tenderizers, you’ll find papain, an enzyme found in unripe papayas. That’s what really does the job. All that salt is there primarily to dilute and spread out the relatively small amount of papain in the product on … Read more

What’s So Special About Those Expensive Popcorn Salts and Margarita Salts Sold In Supermarkets?

Chemically speaking, absolutely nothing. They’re plain old salt: sodium chloride. But physically speaking, they’re either finer-grained or coarser-grained than ordinary table salt. And that’s all. The number of specialty salts on the wholesale market is astounding. Cargill Salt, Inc., one of the world’s largest salt producers, makes about sixty kinds of food-grade salt for food … Read more

What Is Salt?

Beneath the surface of Hutchinson, Kansas, and thousands of square miles of its environs lies an enormous deposit of a precious rock-like mineral called halite. There, several huge mining operations extract almost 1 million tons per year, and that’s less than one-half percent of the world’s annual halite production. What do we do with all … Read more

What Is White Chocolate Made Of?

White chocolate is simply the fat from the cacao bean (the cocoa butter) mixed with milk solids and sugar. It contains none of those wonderful, though inauspiciously brown, cocoa-bean solids that give chocolate its unique character and rich flavor. If you choose a white-chocolate-topped dessert to avoid chocolate’s caffeine, bear in mind that cocoa butter … Read more

What Is the Difference Between Dutch Process Cocoa and Regular Cocoa?

To make cocoa, unsweetened chocolate (solidified chocolate liquor) is pressed to squeeze out most of the fat, and the resulting cake is then ground to a powder. There are several types of “regular” cocoa powder, depending on how much fat remains. For example, “breakfast cocoa” or “high-fat cocoa,” as defined by the FDA, must contain … Read more

Where Does Corn Syrup Come From and How Is Corn Syrup Made?

I know what you’re thinking. The corn that you bought at the farmers’ market the other day wasn’t really “as sweet as sugar,” as the vendor promised, was it? “Sweet corn” does indeed contain more sugar than “cow corn,” but even in the new sugar enhanced and super sweet varieties it’s precious little compared with … Read more

How Does Two Cups of Sugar Dissolve In One Cup of Water?

Why don’t you try it? Add two cups of sugar to one cup of water in a saucepan and stir while heating slightly. You’ll see that all the sugar will dissolve. One of the reasons is very simple: Sugar molecules can squeeze into empty spaces between the water molecules, so they are not really taking … Read more

What Is Sulphured Molasses and How Is Sulphured Molasses Made?

The “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 … Read more

What Is the Difference Between Cane Sugar and Beet Sugar?

More 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. … Read more

What Is the Difference Between Raw Sugar and Refined Sugar?

What health-food stores call raw sugar isn’t raw in the sense that it is completely unrefined. It’s just refined to a lesser degree. From the dawn of history, honey was virtually the only sweetener known to humans. Sugar cane was grown in India some three thousand years ago, but it didn’t find its way to … Read more

What Does Entropy Mean and Where Does Entropy Come From?

There’s no such thing as a stupid question. This is perhaps the most profound question in all of science. Nevertheless, it does have a fairly simple answer ever since a genius by the name of Josiah Willard Gibbs (1839–1903) figured it all out in the late nineteenth century. The answer is that everywhere in Nature … Read more

Why Doesn’t Soap Work In Sea Water or Salt Water?

It’s one of life’s little ironies. Sailors do hard, often dirty work, yet with all that water around they can’t bathe or wash their clothes with soap. Not with ordinary soap, anyway. There is a special soap called “sailors’ soap” that works in salt water. But first let’s see why the ordinary stuff doesn’t. It … Read more

Why Is One Side of Aluminum Foil Shinier Than the Other?

It’s because of a time and space-saving shortcut that’s used in the final stage of the manufacturing process. Aluminum, like all metals, is malleable; that is, it will squish when enough pressure is applied. That’s in distinction to most other solid materials, which will crack under pressure. So metals can be rolled out into extremely … Read more

Why Do Smoke Alarms Contain Radioactive Material: Americium-241?

What you have is an ionization-type smoke detector. It detects smoke by the fact that smoke interferes with air’s ability to conduct a tiny electric current. Under ordinary conditions, air doesn’t conduct electricity at all; it’s an excellent insulator. That’s because the nitrogen and oxygen molecules in the air have no electric charge of their … Read more

Why Does the Two Potato Clock Need Two Potatoes?

For the same reason that your flashlight needs two batteries. A set of zinc and copper metals will move electrons with only so much oomph. That’s because there’s only a certain amount of difference between the electron-holding powers of zinc and copper. But if you need more electron-moving force, to light a bulb, for example, … Read more

How Do Kids Jump Over Things On Their Skateboards?

An ollie, is named after its inventor, Allen Ollie Gelfand. Gelfand was one of a number of southern California surfers in the late 1950s who just couldn’t wait for good surf to come up and decided to surf the sidewalks. That’s what started the skateboard craze. An ollie is a jump into the air without … Read more

Why Are New Tires So Much Noisier Than Old Tires?

One obvious factor is that your old tires may have been pretty smooth, and smoother tires will be quieter. Tire noise depends on the tread pattern, the roughness of the road and the roundness of the tires. Really, tires can be out-of-round, and the high spots will thump on the road during every revolution. But … Read more

Why Does Rubber Stretch?

If there is one statement that will make you a passionate believer in molecules, it’s this: Rubber stretches because it is made of stretchy molecules. A rubber band stretches because each of its molecules, all by itself, is built like a miniature rubber band. Rubber molecules are shaped like long, skinny worms, all coiled and … Read more

How Does an Eraser Erase Pencil Marks?

It doesn’t work like a chalkboard eraser, which wipes an accumulation of chalk off a smooth surface. Paper isn’t that smooth and a pencil mark isn’t all on the surface; most of it is embedded among the paper fibers. If you look at a pencil mark under a microscope, you’ll see that it’s not continuous; … Read more

Why Can You Smell When It’s Going To Rain?

It’s not the rain itself that you smell, but just about everything else. Almost everything smells a little stronger when it’s about to rain. Stormy weather is usually preceded by a drop in atmospheric pressure, or what the TV weather people like to call “barometric pressure.” (Is that what you feel when you’re struck by … Read more

Why Does Warm Air Hold More Moisture Than Cold Air?

It’s usually more humid in the summer because there’s more water vapor available. I don’t mean that the oceans, lakes and rivers somehow expand in the heat. (Well, maybe a tad.) More precipitation? Perhaps. But it’s not the amount of water itself; the humidity can be quite low over the middle of the ocean. What … Read more

Why Does a Hair Dryer Have To Both Heat and Blow?

This is one of those questions that seems so natural that we forget to ask them. But that’s what I’m here for: to make you wonder about things you take for granted, and then to replace your complacency with the smugness of knowing. The water in your hair or clothes must first be converted from … Read more

What Does 100 Percent Humidity Mean and Does It Mean Rain?

Chicken Littles who fear drowning in air are forgetting that “humidity” is purely relative. Everybody goes around talking about “the humidity” as if it’s something absolute, but it’s really the relative humidity that they’re talking about, relative to some maximum, but still small, amount of water vapor in the air. And mind you, that’s vapor, … Read more