Cooking makes all sorts of interesting transformations in raw foods to whet the appetite, delight the taste buds, and nourish the body.
It softens some foods like the celery stalk, the potato, and the grain of rice. It makes others firm like the egg, the cake batter, and the meringue. It enlarges some things, such as popcorn, popovers, and souffles; deflates some (spinach, for one); and makes others disappear altogether, like a liquid left forgotten on a hot burner or the alcohol in cherries jubilee.
Color Me Healthy – Cooking of Benefits
Cooking changes colors turns the brown lobster red and the red meat brown. The green vegetable too if you cook it too long and it changes butter from yellow to brown to black. It can bind foods together, as it does in sauces and cream soups and croquettes. It can break foods down like curdled milk, overheated hollandaise.
It tenderizes flesh or toughens it, depending on how it is done. It can thin gelatin and thicken broth, liquefy fat and crystallize maple syrup. It makes some foods more nourishing by making their nutrients more available to the body, yet it can destroy other nutrients, such as vitamins. It can make foods safer to eat by killing disease producing organisms.
It does remarkable things with taste, blends and mellows flavors, heightens them, sometimes transforms them entirely, sometimes ruins them by burning, scorching, or just plain cooking too long.
The changes just mentioned all come about through a single process, which use applying heat over a period. That is what cooking is: bringing about a change in a food product by the application of heat over a period of time. The overall purpose of cooking is to make the food more edible. Speaking in the language of the kitchen, we say we are increasing its playability.
Notice that two things are necessary in cooking to bring about change: heat and time. You will find that many specific cooking techniques have to do with the interplay of these two factors: the length of time and the degree of hotness, or the temperature.
When we talk about cooking temperature, we are usually talking about the temperature of the cooking medium like the fat in the fry kettle, the air in the oven, the water in the pot. The real purpose, of course, is to raise the temperature of the food itself to the point where the desired change will take place. This is what takes time. The lower the temperature of the cooking medium, the longer it takes to bring about change.
In the ever-changing world of ours, we find more and more new ways that save us time cooking. This is because we have less time to prepare food in our busy lives. Having a job in the food industry is one way to kill two birds with one stone. You can work all day and bring home a good meal for the family after work. If everyone could spend his or her lives cooking for money, I would bet most of us would do it.
Equipment for oven and broiler cooking
A small overhead broiler known as a salamander is common in restaurant kitchens for quick glazing and browning of a product that is already cooked. The salamander is usually mounted over the range.
In overhead broilers, there are two ways to control the cooking temperature. You can move the cooking surface toward the fire or away from it, or you can turn the heat up or down. Broilers, like other cooking equipment, should be preheated before use.
The cooking methods generally called frying are classified as dry heat methods. To fry is to cook food in hot fat. It includes the following methods.
Panfry To cook food in a small to moderate amount of fat over moderate heat.
Deep-fry To cook food submerged in hot fat.
Saute (sotay) to flip food quickly in a small amount of hot fat in a pan over high heat.
At first glance, you might think that frying is a moist heat method, since the medium that conducts heat to the food is a liquid. Fat, however, does not contain moisture. Moreover, it does not interact with the food in the way that liquids do in moist heat cooking. Fat may become part of a finished product by being absorbed in the food’s coating, but in good fat cookery the temperature is hot enough for the food to cook quickly with a minimum of fat absorption. A greasy product is never desirable.
Frying in all its forms is a quick cooking process suitable for small tender foods such as eggs, fish, chicken pieces, chops, and soft vegetables, or for foods partially cooked by some other method, such as deep-fried potatoes or Coquettes made from cooked chicken. It is not a suitable method for large products or foods needing long slow cooking.
Now let us look at the ways in which the various frying methods differ. Deep-frying, pan-frying, and sauteing differ for fat used. In deep-frying, the food is surrounded by hot fat. In pan-frying, a small to moderate amount of fat is used. In sauteing, little fat is used.
In deep-frying, the food is exposed to heat on all sides at once and cooks quickly and evenly. In pan-frying and sauteing, it must be turned or flipped to expose all sides to the hot fat.
Pan-frying differs from sauteing in several ways. One is a time and temperature difference: sauteing is done quickly at high heat, while pan-frying uses moderate heat and slower, more deliberate cooking. Another difference is that pan-frying is generally used for larger pieces of food such as fish fillets or chicken pieces. While sauteing cooks smaller, equal sized pieces of food, such as thin slices of veal or beef or vegetables, in a smaller amount of fat.
Perhaps the most interesting difference is that pan-frying is a quiet process that takes little of the cook’s attention, and sauteing is an active process demanding the cook’s full participation. To pan-fry, the cook places the foods in the hot fat and they cook by themselves until they are ready to be turned. To saute, the cook adds the foods to sizzling fat and then shakes the pan back and forth vigorously to keep them in motion.
HOW TO CARE FOR FAT FOR THE FRYER
Keeping fat for the deep fryer ready for cooking takes a special kind of care that goes on before, during, and after cooking.
To begin with, you must use the right kind of fat. A suitable fat is one that is odorless and tasteless and can withstand the continuous high temperatures needed without smoking or breaking down-that is, changing in chemical structure. Animal fats (meats, fish, poultry, butter) and olive oils are unsuitable because they have distinctive tastes and they smoke at low temperatures. Most vegetable oils are not stable enough. The best fats are certain vegetable oil products that have been specially processed to increase their stability. Such fats are hydrogenated; meaning that extra hydrogen has been added to their chemical structure to make them more stable.
Even good fat is easily broken down by carelessness in use or storage. Overheating, by exposure to copper, by salt, water, crumbs, and certain fatty foods can cause breakdown. When fat breaks down it cooks poorly, tastes bad, and must be discarded. Have you ever tasted rancid or fishy flavored fried foods at a fly by night snack shack or a roadside Greasy Spoon?
If you take good care of it, fat will stay fresh and can be used several times. Care pays off, since good cooking fat is very expensive. Here are some important rules of care.
Heat fat very gradually to cooking temperature. Do not let the temperature go above 200°F (100°C) until the fat all around the heating element is liquid.
Keep salt, water, and loose crumbs away from the fryer. Drain wet foods such as potatoes before frying. Bread products with care for a firm coat. Skim off crumbs that surface during cooking.
Do not deep fry fatty foods.
Strain fat at least once a day, oftener if volume is heavy. Use a special fat strainer or several layers of cheesecloth or a paper filter in a china cap or strainer.
Add fresh fat after each day’s use-oftener if needed-to replace fat absorbed by foods during frying. The fresh fat helps to maintain the quality of the fat as a whole. Daily fat replacement should total 20 percent or more of the total amount. This continuing replacement is known as fat turnover. But . . .
Do not add good fat to bad fat. It will not restore quality. Add fresh fat only to fat in good condition. Throw bad fat out.
If fat breaks down, replace it entirely. Be alert to these signs of breakdown: off flavors (taste fat daily); smoking at cooking temperatures; yellow foam while cooking (good fat produces clear, distinct white bubbles).
Remove the fat and clean the fryer after each day’s use, oftener if needed.
Store fats and oils, covered, in a cool, dark dry place.
Cooking is a way to change plain raw foods into delectable dishes that please the customer, supply the schoolchild with energy, and help to make the patient well. The way we bring about such changes is to apply heat to foods over a period of time. We can do this in a number of ways.
How heat affects food substances
In addition to temperature and time, the makeup of the food itself is a determining factor in the changes cooking brings about. Foods are made up of varying combinations of the following substances:
3. Fats and oils
4. Vitamins and minerals
Nutritionally these substances, taken together, provide energy (measured in calories); they build and maintain bones, body tissues, and blood cells; and they keep everything in working order. In a well balanced diet, protein should provide 10 to 15 percent of the calories, carbohydrates 55 to 58 percent, and fats and oils not more than 30 percent. Vitamins, minerals, and water contribute no calories but are essential to growth and health. One of the goals of good cooking is to conserve the nutrient values of foods.
These different components of foods react in certain distinctive ways to the heat of cooking. If you understand these reactions, you can control the changes and obtain the results you want.
Foods high in protein are the flesh foods (meats, poultry, fish), milk products, eggs, nuts, and certain vegetables. Nutritionally, proteins are the major building and maintenance materials of the body. On the menu, foods high in protein are the entrees, the backbone of the meal.
In cooking, heat causes proteins to coagulate, to become firm, join, cohere. You can see this happen before your eyes if you fry an egg over low heat: the transparent liquid becomes white and opaque as the heat reaches it. If you cook it too long or at too high a temperature, it toughens and thus becomes too firm. The same thing happens in flesh cookery: as the temperature of the product increases, the protein firms. Overcooking will make the flesh tough.
If you heat milk too rapidly or too long, its protein will coagulate into curds and separate from the liquid whey, and we say it has curdled. This will spoil your soup, sauce, or custard. Cheese, which is made from milk curd, reacts to high or prolonged heat by quickly becoming tough, stringy, and unmanageable.
Connective tissue in meats is formed of certain kinds of protein that are naturally tough. The type known as collagen can be broken down and changed into gelatin by cooking at low temperatures with moisture. Acids can also soften meat fibers to some extent, as in marinating on the other hand; acid can reinforce the coagulation process. Adding vinegar to the water in which eggs are poached makes a firmer, more compact and shapely product.
Carbohydrates include starches, sugars, and cellulose, or fiber They are found mainly in plant foods such as cereal grains, vegetables, and fruits; in products made from cereal grains such as flours and cornstarch; in milk; and in refined sugar products such as granulated sugar and sugar syrups.
Nutritionally, starches and sugars are the body’s main sources of energy. Those from grains, rice, fruits, and vegetables are the most useful to the body, while refined sugar is often said to contribute “empty calories.” On the menu, starches and sugar are served in bread and rolls, desserts, rice, pasta, cereal, potatoes and some other vegetables, and many soups and sauces.
In cooking, heat affects the three types of carbohydrates in different ways. With starches, the most important change that heat brings is gelatinization. This is the process by which dry starch granules (flour, cornstarch, and so on) absorb moisture in the presence of heat, thickening and binding the food with which they are mixed. This is an important part of making soups and sauces, and it plays a role in baking. You will understand gelatinization better when we deal with these products. Acid can affect this process too: adding lemon juice, tomato, or wine can result in a thinner product unless it is added at the end after gelatinization is complete.
The most important change heat brings to sugar is caramelization. High temperatures will cause chemical changes in sugars that alter their flavor and color, turning them brown. The heat must be dry: if water is present the sugars will dissolve, and because they are then limited by the boiling point of water they cannot reach high enough temperatures to caramelize until most of the water has evaporated.
Sugar can be caramelized by itself, or the sugar contained in a food product can be caramelized, as in the browning of baked goods and the caramelization of sugar in browned onions and in hash browned potatoes. Similar browning occurs in meats seared or sautéed at high temperatures.
Cellulose, or fiber, is the substance that gives structure and texture to fruits, vegetables, and grains. The effect of heat on fiber in the presence of moisture is to soften it. This will make it more palatable, up to a point. However, a certain firmness of texture is often desirable. One of the marks of the skilled cook is the ability to produce the exact texture desired in cooked fruits, vegetables, and such starchy foods as pasta and rice.
Fats and oils
Fats and oils are characteristic components of meats, poultry, some fish, many dairy products, nuts, egg yolks, and certain vegetables. As nutrients they provide energy to the body and play an essential role in its functioning. However, fats can also be health hazards. Too much fat in the diet, especially saturated fat (animal fats, butter, and shortenings) and fat related substance called cholesterol might cause heart disease and cancer.
In addition to fats found in menu foods, fats and oils are used as ingredients in recipes and as the cooking medium in frying. Some, such as butter, lard, and shortenings (hydrogenated oils), are solids at room temperature and go from solid to liquid as heat is applied. Oils are liquid at room temperature; they are generally extracted from vegetables such as soybeans, corn, olives, and nuts. As temperatures increase, fats will eventually break down or undergo chemical change. This change becomes visible when they begin to smoke. Breakdown and smoke points differ for different kinds of fats.
Fats and oils Most fat can reach much higher temperatures than water can. The fat in the fry kettle often cooks at 375°F (190°C), whereas water does not go above its boiling point of 212°F (100°C).
In meats and poultry, fats contribute much of the flavor. The flavor of fat used in cooking is often added to the food cooked. The flavor of broken down fat can spoil the palatability of a food that has been cooked in it.
Minerals and vitamins
Minerals and vitamins are minute components in foods that are important to nutrition. Vitamins found in vegetables are easily lost in cooking. Some are water-soluble and may be thrown out with the cooking liquid. Others are sensitive to high or prolonged heat. Cooking with minimum nutrient loss is among the most challenging of cooking problems.
Heat also brings about chemical changes that affect both color and flavor in foods. This becomes a problem particularly in cooking vegetables. Good cooking techniques can help to retain the natural colors and flavors in foods.
Water or moisture, as we often refer to it is the major ingredient in most foods. Fresh raw meats, fruits, and vegetables are at least 70 percent water; some fruits are as much as 96 to 98 percent. The water in a food contains much of its flavor and many of its nutrients.
The effect of heat on the water in foods is very important in cooking them and in the finished product. The water in a food does a good deal of the cooking by conveying heat throughout the product. Moisture also helps to soften certain tough connective tissues in meat, as noted earlier.
On the other hand, the heat of cooking causes the product to lose moisture and with it can go flavor, nutrients, and the moist, tender texture that makes food palatable.
Applying heat in cook
How does the cook apply heat to a food to raise its temperature and bring about change? Heat can be transferred to food in three ways: by conduction, by convection, and by radiation.
Conduction is the transfer of heat from something hot to something touching it that is cooler. For example, heat from the fire passes to a pot; the pot conducts heat to liquid contained in it; the heated liquid conducts heat to any food submerged in it; a vegetable, an egg, a lobster.
Conduction also takes place within food: the eggshell in the hot liquid conducts heat to the egg; the outer portions of the egg or of any food to conduct heat to adjacent portions, so that heat is transferred continuously within it. The fat in the fryer conducts heat to the breading, which conducts heat to the breaded food. The larger the product, the longer it takes for heat to be transferred to the center.
Creative Cooking 101
First imagine that you are completely without electricity or natural gas. How can you prepare your family a hot meal? If you have some briquettes, foil, a grill and duct tape you can bake just about anything you want.
To make your cardboard oven you will need a box with a removable lid or for a collapsible oven a box that you have removed the top and bottom. Next you will want to cover ALL exposed areas of the box with heavy-duty aluminum foil. Cut open a large plastic roasting bag and fasten securely over the top of the box with duct tape or string. There you have an instant oven complete with viewing window. To make this oven with a box that has a removable cut a large whole in the lid. Cover completely inside and out with foil, tape the roasting bag over the hole and you have your oven.
To use this oven, you will first need to prepare you coals. Each briquette supplies approximately 40% F of heat and will hold this heat for about 1 hour. Additional hot briquettes can be added as needed. So to bake a casserole for one hour at 350% you would need 9 briquettes. Temperatures will vary with the box size and weather. To get an accurate temperature reading you may want to invest in an oven thermometer.
Once the coals are hot place them in a tin pan or on foil. Next place a grill or baking pan 6-8 inches above the hot coals. (Use a folding grill or place on empty soup cans.) Place you food on the grill and set the box oven over the food, grill and coals. To provide air circulation prop one end of the box with a rock or cut an air vent on the bottom edge of the box.
For any of you wondering if this really works, YES it does. When I was the director of our Girl Scout Day Camp, I baked two fruit cobblers in box ovens. The fresh wild blackberry one went first with the peach following a close second. My suggestion is you make your oven ahead of time and give it a try. Take it on your next cam-pout and bake some Lasagna.
A word of caution: NEVER, EVER use this oven inside of your house or other enclosed area. Always use it outdoors.
Another way for you to prepare your meal is with the use of a butane stove. This stove can be used safely inside but I recommend that you still have a door or window open to help keep the air fresh. These stoves come in single or double burner models and are very efficient. They work similar to a propane stove the canisters of butane are smaller. One canister can last as long as 8 hours depending on the temperature you cook at, wind and the weather. I like using a cast iron pan when I cook on my butane stove just because the pan is sturdy and the heat gets evenly distributed. Butane Stove Here is what one of these stoves looks like:
Yet another way to prepare a quick bowl of soup or other meal is with this homemade backpacking stove
I hope these ideas have gotten your creative juices flowing. Try these cooking methods out before a disaster or long-term power outage hits you. You will have fun experimenting and be much better prepared for that time you may have to use these methods.