Salt, Fat, Acid, Heat. Samin Nosrat
Чтение книги онлайн.
Читать онлайн книгу Salt, Fat, Acid, Heat - Samin Nosrat страница 8
Название: Salt, Fat, Acid, Heat
Автор: Samin Nosrat
Издательство: Ingram
Жанр: Кулинария
isbn: 9781782112310
isbn:
HOW SALT WORKS
Cooking is part artistry, part chemistry. Understanding how salt works will allow you to make better decisions about how and when to use it to improve texture and season food from within. Some ingredients and cooking methods require giving salt enough time to penetrate food and distribute itself within it. In other cases, the key is to create a cooking environment salty enough to allow food to absorb the right amount of salt as it cooks.
The distribution of salt throughout food can be explained by osmosis and diffusion, two chemical processes powered by nature’s tendency to seek equilibrium, or the balanced concentration of solutes such as minerals and sugars on either side of a semipermeable membrane (or holey cell wall). In food, the movement of water across a cell wall from the less salty side to the saltier side is called osmosis.
Diffusion, on the other hand, is the often slower process of salt moving from a saltier environment to a less salty one until it’s evenly distributed throughout. Sprinkle salt on the surface of a piece of chicken and come back twenty minutes later. The distinct grains will no longer be visible: they will have started to dissolve, and the salt will have begun to move inward in an effort to create a chemical balance throughout the piece of meat. We can taste the consequence of this diffusion—though we sprinkle salt on the surface of the meat, with the distribution that occurs over time, eventually the meat will taste evenly seasoned, rather than being salty on the surface and bland within.
Water will also be visible on the surface of the chicken, the result of osmosis. While the salt moves in, the water will move out with the same goal: achieving chemical balance throughout the entire piece of meat.
Given the chance, salt will always distribute itself evenly to season food from within, but it affects the textures of different foods in different ways.
How Salt Affects . . .
Meat
By the time I arrived at Chez Panisse, the kitchen had already been running like a well-oiled machine for decades. Its success relied on each cook thinking ahead to the following day’s menu and beyond. Every day, without fail, we butchered and seasoned meat for the following day. Since this task was a classic example of kitchen efficiency, it didn’t occur to me that seasoning the meat in advance had anything to do with flavour. That was only because I didn’t yet understand the important work salt was quietly doing overnight.
Since diffusion is a slow process, seasoning in advance gives salt plenty of time to diffuse evenly throughout meat. This is how to season meat from within. A small amount of salt applied in advance will make a much bigger difference than a larger amount applied just before serving. In other words, time, not amount, is the crucial variable.
Because salt also initiates osmosis, and visibly draws water out of nearly any ingredient it touches, many people believe that salt dries and toughens food. But with time, salt will dissolve protein strands into a gel, allowing them to absorb and retain water better as they cook. Water is moisture: its presence makes meat tender and juicy.
Think of a protein strand as a loose coil with water molecules bound to its outside surface. When an unseasoned protein is heated, it denatures: the coil tightens, squeezing water molecules out of the protein matrix, leaving the meat dry and tough if overcooked. By disrupting protein structure, salt prevents the coil from densely coagulating, or clumping, when heated, so more of the water molecules remain bound. The piece of meat remains moister, and you have a greater margin of error for overcooking.
This same chemical process is the secret to brining, the method in which a piece of meat is submerged in a bath of water spiked with salt, sugar, and spices. The salt in this mixture, or brine, dissolves some of the proteins, while the sugar and spices offer plenty of aromatic molecules for the meat to absorb. For this reason, brining can be a great strategy for lean meats and poultry, which tend to be dry and even bland. Make Spicy Brined Turkey Breast, and you’ll see how a night spent in a salty, spicy bath will transform a cut of meat that’s often devastatingly dry and flavourless.
I can’t remember the first time I tasted—consciously, anyway—meat that had been salted in advance. But now I can tell every time I taste meat that hasn’t. I’ve cooked thousands of chickens—presalted and not—over the years, and while science has yet to confirm my suspicions, I’ll speak from experience here: meat that’s been salted in advance is not only more flavourful, it’s also more tender, than meat that hasn’t. The best way to experience the marvels of preseasoned meat for yourself is with a little experiment: the next time you plan to roast a chicken, cut the bird in half, or ask your butcher to do so for you. Season one half with salt a day ahead. Season the other half just before cooking. The effects of early salting will be apparent long before the first bite hits your tongue. The chicken salted in advance will fall off the bone as you begin to butcher it, while the other half, though moist, won’t begin to compare in tenderness.
When salting meat for cooking, any time is better than none, and more is better than some. Aim to season meat the day before cooking when possible. Failing that, do it in the morning, or even in the afternoon. Or make it the first thing you do when collecting ingredients for dinner. I like to do it as soon as I get home from the grocery store, so I don’t have to think about it again.
The larger, denser, or more sinewy the piece of meat, the earlier you should salt it. Oxtails, shanks, and short ribs can be seasoned a day or two in advance to allow salt time to do its work. A chicken for roasting can be salted the day before cooking, while Thanksgiving turkey should be seasoned two, or even three, days in advance. The colder the meat and surrounding environment are, the longer it will take the salt to do its work, so when time is limited, leave meat on the worktop once you season it (but for no longer than two hours), rather than returning it to the fridge.
Though salting early is a great boon to flavour and texture in meat, there is such a thing as salting too early. For thousands of years, salt has been used to preserve meat. In large enough quantities, for long enough periods of time, salt will dehydrate meat and cure it. If dinner plans change at the last minute, a salted chicken or a few pounds of short ribs will happily wait a day or two to be roasted or braised. But wait much longer than that, and they will dry out and develop a leathery texture and a cured, rather than fresh, flavour. If you’ve salted some meat but realise you won’t be able to get to it for several days, freeze it until you’re ready to cook it. Tightly wrapped, it’ll keep for up to two months. Simply defrost and pick up cooking where you left off.
Seafood
Unlike meat, the delicate proteins of most fish and shellfish will degrade when salted too early, yielding a tough, dry, or chewy result. A brief salting—about fifteen minutes—is plenty to enhance flavour and maintain moisture in flaky fish. 2.5cm -thick steaks of meatier fish, such as tuna and swordfish, can be salted up to thirty minutes ahead. Season all other seafood at the time of cooking to preserve textural integrity.
Fat
Salt requires water to dissolve, so it won’t dissolve in pure fat. Luckily, most of the fats we use in the kitchen contain at least a little water—the small amounts of СКАЧАТЬ