Salt, Fat, Acid, Heat

by Samin Nosrat

  Browning and Flavor

  Continue heating proteins in the presence of carbohydrates, and a remarkable thing happens: the Maillard reaction, heat’s most significant contribution to flavor. Compare bread to toasted bread, raw to seared tuna, boiled to grilled meat or vegetables. In each case, the browned version is much richer and more delightfully complex in flavor, a result of the Maillard reaction.

  This transformation reorganizes aromatic compounds into entirely new flavors. In other words, in browned versions of a food we can experience flavors that don’t exist in the pale version! In Acid, I described the ways in which the Maillard reaction can produce sour flavors in a food. Any food that undergoes the Maillard reaction—browned meats, vegetables, breads—can also develop savory aromas such as floral, onion, meaty, vegetal, chocolatey, starchy, and earthy flavors in addition to the flavors of caramelization. Because surface browning is often accompanied by dehydration and crispness, it can also leads to the contrasts in texture, as well as flavor, that so delight our palates. My very favorite French pastry of all time, the canelé, is the pinnacle of this sort of juxtaposition: its tender, custardy center is enveloped by a dark, chewy crust altered by caramelization and the Maillard reaction.

  Browning begins at around 230°F—well past the boiling temperature of water and the coagulation point of proteins. Since the temperatures required to achieve this kind of tasty browning will dry out proteins, beware. Use intense heat to brown the surface of meats and quickly cook tender cuts such as steaks and chops through. After browning a tougher cut such as brisket, on the other hand, use gentle heat to keep its interior from drying out. Or do the opposite and cook it through with gentle heat. Then, once the meat is tender, increase temperatures to brown the surface.

  Browning is an invaluable flavoring technique, but it must be done with care. Heat that’s uneven or too powerful can take food straight past golden delicious to charred. But sear a steak too timidly, and you’ll overcook it before it has a chance to brown.

  Learn to take browning fearlessly to the edge, because that’s where the deepest flavors lie. Try another little experiment: make two half-batches of Salted Caramel Sauce. Stop cooking one half when you normally would, but cook the other a few shades darker. Drizzle both, side by side, onto vanilla ice cream and taste to understand how much more flavor a few moments on the stove can yield. Or, next time you plan to braise short ribs or chicken legs, brown half of the meat in the dry heat of the oven, and the other half on the stove to see how the different forms of heat in each method yield different results (for a hint, read on to Roasting).

  As with all good things, including salt, you can take browning too far. The next time you dare to call burnt bacon or nuts “crisp,” think of the time one of my cooks at Eccolo did so, only to spot Alice Waters seated at the bar, gingerly picking the too-dark hazelnuts out of her salad. Having just served a culinary legend a dish he’d known was unsatisfactory, he went into the walk-in refrigerator, lay down on the floor, and cried. Though I felt terrible for him when I found out, all I could do was laugh and encourage him to learn from his mistake. Most of the time, you don’t need anyone else to tell you things aren’t right; be your own Alice Waters.

  Temperature’s Effects on Flavor

  It’s tempting to think that cooking begins with the click of the gas burner or the turn of the oven dial. It doesn’t. Cooking begins much, much earlier, with the temperature of your ingredients.

  To begin with, the temperature—that is, the measure of heat, or of its absence—of an ingredient will affect how it cooks. Food at room temperature cooks differently than food straight from the fridge. The same food will cook evenly or unevenly, quickly or slowly, depending on its temperature at the start of cooking. This is particularly true for meat, eggs, and dairy, whose temperamental proteins and fats are deeply affected by temperature swings.

  Take, for example, the chicken you’re thinking about roasting for dinner. Slide the chicken directly from the fridge into the oven, and by the time enough heat penetrates to cook the legs through, the breast meat will have overcooked, resulting in tough, dry meat. But let the bird come to room temperature on the kitchen counter before roasting and the bird will spend a shorter time in the oven, limiting the opportunity for overcooking.

  Because the chicken is so much more dense than the hot oven air, the twenty-five-degree difference in the temperature of the bird when you start cooking it—the approximate differentce between fridge and room temperature—is substantially more important than a twenty-five-degree difference in oven temperature. You could cook a room-temperature bird at 400°F or 425°F and not see much of a change in cooking time or result. If you cook a cold bird, the cooking time will increase dramatically and dry, tough breast meat will be apparent from your first bite. Let all meats—except for the thinnest cuts—come to room temperature before you cook them. The larger the roast, the earlier you can pull it out of the fridge. A rib roast should sit out for several hours, while a chicken needs only a couple, but when it comes to tempering meat, any time is better than none at all. Get in the habit of pulling out the meat you plan to cook for dinner right when you get home from work (and salting it, too, if you haven’t already), and you’ll learn that time can do some of the work of good cooking even better than the oven can.

  And just as cooking doesn’t begin when the flame is lit, nor does it end when the flame dies out. The chemical reactions generated by heat develop momentum, and they don’t stop the second you turn off the flame. Proteins in particular are susceptible to carryover—continued cooking that results from residual heat trapped within a food. Use this knowledge to your advantage, knowing that roasts carry over five to ten degrees Fahrenheit on average after they are removed from heat, and that some vegetables, such as asparagus, do too, as well as fish, shellfish, and custards.

  Apart from affecting how food cooks, temperature also affects how it tastes. For example, some tastes, when warm, trigger pleasure responses in our brains.

  Many of food’s most aromatic molecules are volatile, meaning that they can evaporate into the surrounding air. The more of a food’s aromatic molecules we can breathe in, the more powerful our experience of its flavor will be. Other flavor molecules are liberated for us to taste as heat degrades the cell walls that confine them. By increasing their volatility, heat sets a greater number of aromatic molecules free, allowing them to permeate the environment more fully. The smell of a tray of warm chocolate chip cookies can fill a room, whereas cookie dough, still clinging to its aromatic compounds, neither smells nor tastes as compelling.

  Sweet, bitter, and umami tastes are more intense and send stronger signals to the brain when food is warmer. As any college student can tell you, the same pint of beer, while delicious chilled, will be unpalatably bitter at room temperature. Or try a bite of cheese straight from the fridge. It won’t taste like much. Let the cheese come to room temperature. As it warms, its fat molecules relax, releasing entrapped flavor compounds. Taste the cheese again, and you’ll perceive new dimensions of flavor that weren’t available before. Fruits and vegetables, too, taste different at various temperatures. Volatile compounds in some fruits, such as tomatoes, are so delicate that the cold of the refrigerator can make them less available—making a good case for storing and eating them at room temperature.

  There’s a case to be made for serving food warm or at room temperature rather than blazing hot. Researchers posit that excessive heat impairs our ability to enjoy the flavor of food. Besides burning our taste buds, hot food is harder to taste. The perception of taste decreases when a food’s temperature rises beyond 95°F. While some foods, such as many pasta dishes and fried fish, suffer if they’re not served immediately after coming out of the pan, most others are more forgiving.

  Over the years, I’ve grown to prefer serving warm and room-temperature food at gatherings. Try throwing a dinner party where you don’t serve anything hot. Prepare marinated roasted or grilled vegetables; sliced roast
ed meats; grain, noodle, or bean salads; frittatas and hard-cooked eggs. Besides tasting better, hosting a dinner this way is also a lot less stressful than trying to herd guests and rush a soufflé to the table!

  The Flavor of Smoke

  Smoke, that wispy consequence of heat, conveys a powerful flavor to food. Most of smoke’s flavor is in its aroma, and it’s one that triggers ancestral memories of the earliest kind of cooking: over fire.

  Made up of gases, water vapor, and small particles resulting from combustion, smoke is a by-product of burning wood, which is why I always choose to grill over live fire rather than gas, even though it takes more time and effort. If all you’ve got is a gas grill and you want to impart some smokiness to your grilled meats and vegetables, you can use wood chips. Just soak and drain a couple of handfuls—I love the flavors of oak, almond, and fruit woods—in a disposable aluminum baking pan and cover with foil. Poke several holes in the foil to allow the smoke to escape. Turn on some, but not all, of the burners, place the pan over an unlit spot, and close the lid. Begin cooking once you catch the first appetizing whiffs of smoke. Close the lid to bathe your meat and vegetables in smoky flavors, which result from a series of chemical reactions, including browning. Heat transforms the flavors of wood into the marvelous flavors of smoke, which include aromatic compounds similar to those found in vanilla and cloves. When food is exposed to smoke, it absorbs the sweet, fruity, caramel, flowery, and bready flavor compounds. You’ll see—nothing else compares to the flavor of true wood smoke.

  USING HEAT

  At the heart of good cooking lies good decision making, and the primary decision regarding Heat is whether to cook food slowly over gentle heat, or quickly over intense heat. The easiest way to determine which level of heat to apply is to consider tenderness. For some foods, the goal is creating tenderness, while for others, it’s preserving innate tenderness. In general, foods that are already tender—some meats, eggs, delicate vegetables—should be cooked as little as possible to maintain their tenderness. Foods that start out tough or dry and need to be hydrated or transformed to become tender—grains and starches, tough meats, dense vegetables—will benefit from longer, more gentle cooking. Browning, whether for tender or tough foods, will often involve some form of intense heat, meaning that sometimes you have to combine cooking methods to get the different results you’re after on the surface and within. For example, brown and then simmer meats in a stew, or simmer and then brown potatoes for hash to ensure browning and tenderness in both cases.

  A Note on the Oven

  Baking, the most precise endeavor in the kitchen, is powered by its most imprecise source of heat: the oven. Humans have never had much control over exact oven temperatures, whether in the first ovens, which were little more than pits in the ground heated by wood fire, or in today’s luxe gas-powered models. The only difference is that when ovens were still powered by live fire, no one believed that he or she could control temperature with the turn of a dial. Because the truth is, no one can.

  Set the average home oven to 350°F, and it’ll heat up to about 370°F before the heating element shuts off. Depending on how sensitive the thermostat is, the temperature might drop down to 330°F before the heating element switches on again. Open the oven door to check on the cookies, and cool air will rush in as hot air escapes, dropping the temperature even more. Once the thermostat is triggered, the temperature will head back to 370°F, with the cycle continuing until the cookies are done. The amount of time the oven actually spends at 350°F is negligible. If your oven is miscalibrated—and most are—then 350°F could mean anywhere from 300°F to 400°F, before the heating cycle even begins. It’s all mind-bogglingly imprecise.

  Don’t let the oven’s willy-nilly nature scare you. Instead, be bold: don’t rely on the oven dial. Paying attention to the sensory cues that indicate how food is cooking is far more valuable than minding an arbitrary number. I internalized this lesson the first time I worked the wood-fired spit at Eccolo. I was still a young cook when I arrived back in California, after my travels to Italy and beyond. Constantly doubting myself, I made it easy for the cooks with whom I shared the kitchen to doubt me, too. None of them ever seemed insecure about working the spit, but I was terrified. What did they know that I didn’t?

  Most nights, we roasted skewers of chickens on the spit, over burning oak and almond wood. I had so many questions: How would I know where to build the fire? How would I know how much wood to add, and when? How would I know if the fire was too hot, or cool, and when the chickens were done cooking? How could they expect me to cook anything properly on this crazy contraption when it had no controls, dials, or thermostat?

  Sensing my impending meltdown, the chef, Christopher Lee, took me aside and patiently explained that even though I’d never used a spit, I was prepared. Hadn’t I roasted hundreds of chickens over the years? Didn’t I know that it takes about 70 minutes for a chicken to roast in the oven? Didn’t I know that I could tell when a chicken was cooked when the juice at the thigh ran clear when pricked? I had, and I did. He showed me how heat reflected off the walls of the rotisserie oven just like it did in a gas oven, how it was hotter in the back and cooler in the front just like in an oven, and to treat the birds as if I were roasting them in a big, black box—something I could do with ease. Soon, I realized that spit-roasting looked a lot more complicated than it actually was, and it quickly became my favorite way to cook.

  Relinquish the false sense of control an oven offers, just like I did at the spit. Instead pay attention to how your food is cooking. Is it rising? Browning? Setting? Smoking? Bubbling? Burning? Jiggling? When you read recipes, think of temperatures and cooking times as strong suggestions, rather than fixed rules. Set your timer for a few minutes less than a recipe might suggest, then use all of your senses to check for doneness. Always remember the qualities you seek in your food. Adjust course constantly and accordingly to achieve them. This is what good cooking looks like.

  Gentle Heat versus Intense Heat

  The aim of cooking with gentle heat is always the same: tenderness. Use gentle cooking methods to allow delicate foods—such as eggs, dairy, fish, and shellfish—to retain their moisture and delicate texture. Let gentle heat transform the dry and tough into the moist and tender. Choose among intense heat cooking methods (apart from boiling, which is intense in its own way) when seeking to brown food. When carefully applied to tender meats, intense cooking methods lead to brown surfaces and moist, juicy interiors. For tough meats and starchy foods, combine these methods with gentler ones, in order to achieve the desired browning on the outside and allow low heat to do its gradual work within.

  Gentle Cooking Methods

  • Simmering, Coddling, and Poaching

  • Steaming

  • Stewing and Braising

  • Confit

  • Sweating

  • Bain-marie

  • Low-heat Baking and Dehydrating

  • Slow-roasting, Grilling, and Smoking

  Intense Cooking Methods

  • Blanching, Boiling, and Reducing

  • Sautéing, Pan-frying, and Shallow- and Deep-frying

  • Searing

  • Grilling and Broiling

  • High-heat Baking

  • Toasting

  • Roasting

  Cooking Methods and Techniques

  Simmering

  Since the boiling point of water is such an important kitchen landmark, I’d always assumed boiling to be the most straightforward cooking method: just drop food into a pot of bubbling water and pull it out when it’s done. Then one day, after about a year in the kitchen, as I turned my hundredth pot of boiling chicken stock down to a simmer, a lightbulb went off: when it comes to cooking food in liquid, cooking food through at a rolling boil is the exception rather than the rule.

  I realized boiling is called for only when cooking vegetables, grains, and pasta; reducing sauces; and hard-cooking eggs. I could bring everything else—and I mean everything�
�to a boil and then swiftly reduce it to a simmer to cook through, whether I was cooking over a live fire, on the stove, or in an oven. Since simmering water is gentler than boiling water, it won’t jostle delicate foods so much that they fall apart or agitate tougher foods so much that overcook on the surface before cooking through completely.

  Beans. Braises. Paella. Jasmine Rice. Chicken Vindaloo. Pozole. Quinoa. Stews. Risotto. Chili. Béchamel sauce. Potato gratin. Tomato sauce. Chicken stock. Polenta. Oatmeal. Thai curry. It didn’t matter—this applied to everything cooked in liquid. It was a life-changing revelation!

  Depending on whom you ask, the temperature of simmering water can range from 180°F to 205°F. Look at the pot—is it barely bubbling like a just-poured glass of your favorite sparkling water, beer, or champagne? If so, then cheers—it’s simmering.

  Sauces

  Bring tomato sauce, curry, milk gravy, and mole sauce alike to a boil, then turn down to a simmer to cook them through. Some sauces, such as Ragù Bolognese, take all day. Others, such as pan sauces or Indian butter chicken, cook far more quickly, but the process is the same.

  In general, keep sauces containing fresh milk at a simmer, because some of the proteins in milk can coagulate above temperatures of 180°F, resulting in curdled, grainy sauces. Sauces made from cream contain little to no protein and avoid this risk of coagulation. And milk sauces containing flour, such as béchamel or pastry cream, are an exception to this rule, as flour will interfere with coagulation. Still, remember that the natural sugars in milk and cream are eager to scorch, so once these sauces come to a boil, reduce them to a simmer and stir often to prevent burning.