November 5, 2012
The Science of Good Cooking: Tips From America’s Test Kitchen
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Christopher Kimball on the set of America’s Test Kitchen with Bridget Lancaster. Photo by Daniel J. Van Ackere
In 1983, Christopher Kimball, founder of Cook’s Magazine, received a letter from an irate grandmother unhappy with his presentation of recipes and cooking. “You don’t cook from your heart,” she wrote. Kimball responded in the affirmative. “Yes,” he said, “I cook from my head.”
That approach helped Kimball, a slim man never without his bow tie and glasses, build an empire of inquisitive, science-based cooking with his magazine now named Cook’s Illustrated and PBS shows America’s Test Kitchen and Cook’s Country. Based out of a 2,500-square-foot kitchen outside of Boston, the magazine and television programs offer a tirelessly scrupulous approach to solving the kitchen’s persistent problems: Why does food taste better hot (science)? Does marinating really tenderize meat (no)? How do you get extra fluffy rice (rinse in water)? Kimball says, “The objective is to figure out why bad things happen to good recipes.” Accompanied by his even more fastidious science advisor, Guy Crosby–”working with Guy is like working with a Talmudic scholar”– Kimball tests dozens of different methods for each recipe, all so you don’t have to.
Which is fortunate, because as it turns out, “The science of cooking is actually much more complicated than particle physics or anything else that I’ve discovered,” according to Kimball.
In a world of stylized cooking shows with frequent exclamations of “Yum-o!” Kimball, 61, would appear out of synch. To him, cooking with your heart is as useless an expression as cooking with your pancreas. His delights are in trial and error, mastering the how and why. Stubbornly rigorous, Kimball is still far from a perfectionist. He says, “You never see Martha Stewart start a show saying, ‘This cakes looks terrible!’” But Kimball regularly includes failed recipes on his shows to show how common it is and how easy to overcome.

With scientific explanations of 50 cooking phenomena plus recipes, The Science of Good Cooking prepares the home chef for any challenge
In the recently released book, The Science of Good Cooking, Kimball and company (he works with a staff of more than three dozen) guide the reader through 50 concepts of cooking and more than 400 tested recipes. Perhaps a little more ambitious than physicist Richard Feynman’s Six Easy Pieces, the 50 concepts touch on everything from temperature to tools as a way to enhance not just the recipes in the book, but any dish you attempt in the kitchen.
Some of the tips offered and mysteries explained:
Don’t marinate meat, brine it: Counterintuitive but scientifically proven; salt makes meat juicy. According to the pros, “Salting poultry allows us to reap the benefits of brining as it breaks down proteins and helps to retain moisture within the meat.” The process even makes the skin crispier. Win-win. This is because, when the salt is first applied, through the process of osmosis, water is drawn out of the meat to the surface. But over time as the salt migrates inward, the expelled moisture returns as well, drawing water from the skin to plump the meat and dry the skin. Mouth watering yet? The same actually goes for dried beans, which should be brined instead of soaked. The pros recommend kosher salt but not all kosher salt is the same. “Because of its more open crystal structure, a teaspoon of Diamond Crystal actually contains less salt then a teaspoon of Morton kosher salt.” The book offers this handy conversion: 3 teaspoons of Diamond Crystal=2 1/4 teaspoons Morton.
Serve warm dishes at 98.5 degrees: Scientists, concerned with culinary satisfaction as they are, discovered tiny proteins in our taste buds that allow our sense of taste to be heightened with increased temperature (obviously to a degree, burning your tongue does not enhance flavor). The seemingly optimal temperature is somewhere around 98.5 degrees, depending on the food. Plus, “Much of our perception of flavor comes from aroma,” and, as the book points out, heated molecules are in an excited state more likely to reach our waiting noses. As a caveat, since some dishes are meant to be served cold (revenge not mentioned), the writers say you should flavor cold dishes more aggressively with seasoning.
Rest dough to cut down kneading time: “Kneading is the most enjoyable part of the breadmaking process,” the writers admit. But, they warn, over-kneading is a common sin that leaves the bread with less flavor and poor texture. You’ll know you’ve arrived at this sad place when your dough goes from a “wheaty tan” to a “grayish white.” The text explains that the point of kneading is to break down existing bonds and form stronger, straighter gluten sheets. But overknead, especially with electric mixers and you introduce both heat and air into your dough. The trick: autolyse, a technique first developed in the 1970s. Essentially all you have to do is rest your dough before kneading. The rest process actually takes care of some of the kneading work for you as enzymes go to work breaking down the mess of coiled protein to prepare for those nice gluten sheets later to come. According to the book, “Doughs that were given the 20-minute respite took an average of about five minutes less kneading.”
Fry foods between 325 and 375 using a mix of old and new oil: Nothing is worse than soggy fried chicken. Likewise, nothing is better than perfectly crisp fried chicken. The difference may be a matter of degrees. Most food is fried somewhere between 325 and 375 degrees (French fries, for example, are perfectly crisped at 325 degrees). It’s important to maintain this temperature (one of the reasons you fry in small amounts because dumping a large quantity of food into the pan lowers the overall temperature, warn the writers). Dropping a piece of battered shrimp into hot oil causes the surface moisture to escape in a burst of steam. That allows oil to move in. Too hot and too much moisture is lost meaning too much oil moves in, making the food greasy. But just right and the oil crisps the surface while allowing the meat to cook as well. And as a super secret way to make your food even crisper and more golden, the book recommends saving a cup of used oil to mix with fresh oil. Turns out, oil goes through five different stages while frying (beginning with “break-in” and “fresh” and ending with “degrading” and “runaway”) and right in the middle is the “optimum” oil. Mixing helps you avoid the first batch flop many of us have experienced.
Add milk to scrambled eggs, frozen butter to omelets: If you want scrambled eggs, most of us know to throw in a bit of milk or butter while scrambling. That’s because the lipids in the dairy coat the proteins in the egg (11 percent in the whites and 16 percent in the yolks) and slow down the process of coagulation, a.k.a. when the proteins are denatured and unfurl, releasing much of the water in the mixture. Adding fat helps keep some moisture in and fluff up the final product. But the same does not go for omelets. “While scrambled eggs should be fluffy, an omelet is more compact,” the authors write. While milk works for scrambled eggs, it can add to much moisture to an omelet. The chefs recommend frozen bits of butter instead, which melt more slowly and disperse more evenly. And it turns out you can go ahead and salt the eggs before you even cook them up. Because salt affects the electrical charge on the proteins, it weakens the bonds between them, preventing overcoagulation. Bring that up at your next brunch.
This is just a glimpse into the world of America’s Test Kitchen, where they don’t just find the right fry temperature, they find the individual smoke points of every oil (from coconut to peanut to canola). Precise and tested advice mixed with irresistible-sounding recipes for creamy parmesan polenta, crunchy baked pork chops and Boston cream cupcakes makes for a guide both the experienced home cook and the nervous beginner will enjoy.
“We’re not about gourmet food,” says Kimball. “We just want people to cook at home.”
Even Kimball admits, though, that are some kitchen conundrums he can’t solve. When asked if he’d found a way to really engage his own four kids with the science of cooking he said, “The only thing I’ve proved is they only want to cook with marshmallows and chocolate.”
February 6, 2012
Bedtime Reading From Beatrix Potter: Amateur Mycologist
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One of world’s largest and oldest living organisms also happens to be one of its least-respected. Nicholas P. Money’s most recent book, Mushroom, is something of a corrective and an enthusiastic outpouring for all things fungal—from a 2,400-acre colony of Armillaria ostoyae in Oregon to the supermarket’s white button mushrooms (Agaricus bisporus) right on down to the stuff that makes dandruff (Malassezia). In a testament to his passion, Money criticizes an amateur collector who’s removed a giant bolete the size of her head. “Why do people view mushrooms as so different from other living things?” he says. “Imagine, a meeting of the local Audubon Society that ended with the janitor tossing a sack of songbird eggs in the Dumpster.” Or whaling for research purposes.
Amateur mycologists foster a rare scientific partnership with professionals (a claim that perhaps only astronomers can boast of). Amateurs pioneered the study of mycology and the often-inseparable practice of mycophagy. One of these amateur mycologists was Beatrix Potter. She made careful observations of fungi and lichens, and her watercolors illustrate the 1967 British book Wayside and Woodland Fungi. Potter studied spore germination and wrote a scientific paper, but after being repeatedly snubbed—both for radical botanical views and because she a woman—she turned her attention elsewhere. Money writes:
Potter was, nevertheless, a pioneering mycologist, one whose intelligence and inquisitiveness might have been channeled into a career in science had she possessed the Y chromosome required for most Victorian professions. Fortunately, her considerable artistic talents gave her other outlets for her ambition.
Would The Tale of Peter Rabbit have been conceived had it not been for the biases of Victorian era science? Maybe not. In the paper “Bamboozled by botany, Beatrix bypasses bigoted biology, begins babying bountiful bunnies. Or Beatrix Potter [1866-1943] as a mycologist: The period before Peter Rabbit and friends,” Rudolf Schmid suggests that “her exclusion from botany has been said to have a direct analogy to Peter Rabbit being chased out of Mr. McGregor’s garden, that is, the garden of botany.”
Curiously, though, fungi rarely appear in Potter’s tales, and then mostly as a decorative or whimsical addition. Field mushrooms sprout in The Tale of Squirrel Nutkin; Agaricus campestris is a species squirrels collect, and elsewhere Potter noted their “nasty smell” and “good flavour.” The species also laid the groundwork for cultivated mushrooms and Heinz ketchup. It’s certainly one of the more subtle depictions of food in a genre rift with delightful donkey picnics and a champagne toast between mice.
As many hundreds of times as I’ve heard the story of Flopsy, Mopsy and Peter Cottontail, I never read it as a tale of enthusiasm for the natural world. Yet, at a time when animals are apparently falling out of favor in picture books (at least among Caldecott-award winners), I thought these observations made by an amateur naturalist were a testament to looking, you might say, where no one else had—towards the lowly fungi.
February 1, 2012
Where Jet Engines, Football Fans and Eggs Collide
A quiet whisper contains less than a nanowatt of power. A human shout is a little more than a microwatt, and when you get 68,000 screaming fans inside Indianapolis’ Lucas Oil Stadium—one of the NFL’s louder indoor stadiums—the Super Bowl represents a big game and an incredible source of sound. And all those shouts add up to real power.
In Sound and Sources of Sound, Anne P. Dowling writes: “The total energy radiated by the combined shouts of the Wembley cup final crowd during an exciting game being about that required to fry one egg!” Really? Well, American football fans probably outdo British soccer fans; anecdotal reports suggest that indoor stadiums can reach up to 117 decibels. Still, the question remains: Does the Super Bowl create enough power to fry up a dozen eggs?
I called Mark Sheplak at the University of Florida. He’s a mechanical engineer who has modeled how much power could be harvested from the acoustic liner of an airplane engine. (He’s found that the take-off of many commercial flights can generate the same amount of noise as roughly equal all the human shouts in the world, and this intense concentration of waste noise can be enough to power on-board acoustic monitoring systems.) “I don’t know if there would be enough sound in a stadium to get anything,” he says. “It would have to be really, really loud.”
Before we go much further, it’s also worth pointing out that an egg is a heterogeneous substance. “The various kinds of proteins do not all coagulate at the same temperature,” Herve This writes in Kitchen Mysteries. “One forms at 61°C another at 70°C, and so on….” The combination of cook time and temperature ultimately yields different textures and viscosities (which César Vega writes about extensively in the new book The Kitchen as Laboratory). For the sake of simplicity, let’s forget about any energy lost in cooking—heating a pan or allowing flames to escape around a pan—and take a wild guess at the power required to heat the yolk of a chicken egg to 85°C at sea level. (Engineers and food scientists, please feel free to weigh in). Let’s call it 30 watts to fry an egg: Five minutes of intense screaming.
The bigger problem here is that all these screaming fans are spread out over 1.8 million square feet and, to cook an egg, you would need to concentrate and harvest those sounds and convert them to heat. “You’re usually not terribly efficient,” Sheplak told me, “usually less than one percent efficiency of harvesting that energy. You need to be in a situation where it’s really loud. You can’t have a perpetual motion machine.”
So what might sound like a deafening cacophony during Sunday’s game might actually amount to only a single fried egg, if that. Perhaps thinking about how sports fans might actually cook an egg with their vocal cords demonstrates something else entirely: the pervasive use of the “fried egg” as a scientific analogy.
January 20, 2012
Meringue Chemistry: The Secrets of Fluff
Chefs began whipping up meringue sometime in the early 1600s. The light-as-air confection is made by whipping egg whites and is used in a variety of desserts, such as Pavlova, macaroons and baked Alaska. It’s a delicacy that’s delightfully counter-intuitive. While most other foods get smaller and flatter as they’re beaten and smashed, egg whites are comparatively resilient and fluff up and expand under similar duress.
This past weekend I had a few egg whites left over after making another dish and thought I would try my hand at them. If these things were made by Renaissance chefs in the days before electric hand mixers, surely I could manage to whip some up myself. Unfortunately, mine were a flop—literally. The egg whites never puffed and peaked like they were supposed to; they sat in flat, unappetizing pats on my baking sheet. How could something seemingly so simple fail so spectacularly? Turns out there’s a lot of chemistry to consider when making meringue.
Although egg whites are 90 percent water, the relevant molecules are protein. Proteins are made up of amino acids, some that are attracted to water, others that are repelled by water. One you start beating the whites and introducing air, the water-loving bits cling to the water, the water-repelling bits cling to the air. The more you beat, the more bubbles with a protein coating are created and the more the whole shebang fluffs up. However, bubbles and proteins divided against themselves will not stand, and the foam will collapse without a little stabilizer. One way of doing this is to introduce an acid such as vinegar, lemon juice or cream of tartar, which encourages the proteins in the egg white to bond together. Another ingredient that adds structural integrity, in addition to providing flavor, is sugar, which works like a glue that holds the foam together.
But why don’t we want to use the yolk? This part of the egg contains fat, which interferes with how the proteins line up and coat all those bubbles that are supposed to bulk up your meringue. If the bubbles aren’t properly protected, your meringue will never have much body. This is also why chefs are discouraged from using plastic bowls for this purpose as they have a tendency to retain oils. So perhaps I wasn’t as careful as I ought to have been when separating my eggs and a bit of stray yolk made it into my whites. I’m also in the habit of using my hands to separate eggs. And even though I washed my hands beforehand, perhaps residual oils sabotaged my baking venture. So even though my first try didn’t go so well, tell us about your meringue adventures (or misadventures) in the comments section below.
January 13, 2012
A Closer Look at What You Eat
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San Francisco-based photographer Caren Alpert has captured mouth-watering shots of food, stylish portraits of chefs and glimpses of chic restaurant interiors for clients such as Bon Appetit, Saveur Magazine and the Food Network. But, beginning in 2008, she branched out from her editorial and catalog work to experiment in fine art.
Alpert has taken magnified photographs of foods, from Brussels sprouts to Lifesavers, using a scanning electron microscope at her alma mater, the University of Arizona. Titled “Terra Cibus,” meaning “nurturing from the earth,” the series, recently exhibited at the James Beard Foundation in New York, provides viewers a new, and often bizarre, look at familiar foods.
I spoke with Alpert about the project:
Can you describe the process of preparing the samples and getting the shot?
I choose the foods out here in San Francisco. I sort of curate them if you will. I decide what I want to shoot. I overnight them to the lab in Arizona. They go through a dehydration process and then a metal coating process. Depending on what the food is, the length of dehydration can yield a better result and different metals used in the coating can yield a different result. That is the preparation process.
With a scanning electron microscope you are photographing the surface of a subject or a specimen—in my case, food. I am basically photographing the electrons bouncing off of the surface.
What have been the most interesting foods under the microscope?
The sugar and the salt for sure. I like the kiwi seeds. I love the pineapple leaf (below).
Have you gotten a sense of which foods are photogenic under the microscope and which are not?
I am getting better. But I wouldn’t say I am dead on 100 percent of the time.
I read that you tried a tortilla chip and it was boring looking. Have there been other duds?
Interestingly, it has been difficult to photograph meats and proteins. Bacon, for example—I thought it would be more interesting than it was at first pass. I am trying to find the best way to photograph foods like that, that are higher in fats.
What sort of editing do you do?
The machine captures in black and white only. We do a post-processing treatment back at the studio where we infuse the color of the original foods as best we can.
After photographing a shrimp tail, you went to a scientist at the Monterey Bay Aquarium to inquire about its feathery texture. Do you often take your photographs to outside experts?
Certainly when I am stumped, yes. I am trying to involve more information about what we are looking at. The shrimp tail was quite surprising. Because the Monterey Bay Aquarium is a local gem for us, it was nice to be able to call on them, and they were very receptive to helping out. They were also very surprised to see the image. That is the part of the tail where you hold it and bite it off and then you throw the tail back on your plate. It is right there at that sort of cartilagey intersection.
What have you learned about food from these photographs?
How an unprocessed food or an organic food intakes water or air, you see a lot of that. Processed foods are very sharp and spiky, whereas unprocessed or more organic foods sort of have a repetitive pattern.
Has working on this series changed your own eating habits in any way?
No. Probably the biggest shock—but it hasn’t been enough to change my eating habits—is the French’s fried onions, which you sprinkle over your string bean casserole. They are really irregular and very violent looking compared to some of the others. You would think after seeing it, it would be enough to make you not want to eat them. But they are sort of a guilty pleasure. I snack on those occasionally.
Is healthy eating part of the goal? What do you hope viewers take away from the photographs?
I hope the viewers think about their own choices everyday or how they influence others around them. I got an email a few months ago from a man who said he and his two kids were on my website trying to guess all the foods. Then they would go back to their kitchen cupboards or refrigerator drawers to see if they had any of those foods at home. I think if it can encourage dialogue like that it is really interesting and successful.
I sort of like to encourage the viewer to look at it more aesthetically. I think people are so floored. “Oh my gosh, that is my lunch sandwich or that is my chocolate cake or that is my morning blueberries.” People are just fascinated. They are taken with the beauty of some foods and not others, of course. I got another email from a young woman in Spain who said that she and her boyfriend were fighting about images as art. She thought the images were beautiful and artistic, and he thought, oh, anyone can do that. They were having an argument about what makes art. That’s awesome, you know? It is really encouraging people to think about the parameters they put around those definitions.
More images can be seen at www.carenalpertfineart.com. Prints are available for purchase directly through the photographer.



























