The cooking is the treatment of food with heat to their consistency, taste, digestibility and / or health effect change. After sufficient cooking, the food is called “cooked”. During the cooking process it is also called the “food”. There are different cooking methods. Colloquially , cooking and the general preparation of food are used synonymously with cooking .
Some foods such as legumes , potatoes and pasta only become palatable when they are cooked. Cooking causes a loosening of the tissue, the fiber structure and the cell structure of the food as well as a denaturation of the proteins (also known as protein coagulation), a cell breakdown , a starch gelatinization and a change in taste . Microorganisms are completely killed by the energy supply during cooking or at least reduced to values that are harmless to health (see also: pasteurization , sterilization ). Thermally unstable toxins (e.g. in mushrooms and nightshade plants ) are destroyed by cooking. In addition, the connections between the vegetable or meat fibers are loosened. As a result of the cell breakdown, the cells become perforated, which releases aromas or aroma precursors and facilitates digestion and the absorption of nutrients .
Moist cooking techniques
Moist cooking techniques are cooking techniques with the addition of drinking water . The presence of hot water or steam prevents drying out , but the moist cooking conditions prevent the food from browning .
Cooking is the term used to describe cooking in liquid water at a boiling point of around 100 ° C. You can either add the raw materials when they are cold or add them to the boiling water. The former favors leaching, which is sometimes desired. Cooking is usually done in a metal pot on an electric or gas stove .
A finer distinction is made between “bubbly boiling”, where the water vapor that arises escapes in bubbles and the food is mixed, which z. B. when cooking pasta is desirable. In contrast, the stands Simmern (Engl. (To) simmer ), is supplied at the little heat, ascend no vapor bubbles and the food is gently calm.
When steaming (steaming) food is cooked in steam and not in liquid water. This leaves water-soluble nutrients such as B. minerals and water-soluble vitamins ( vitamins of the B group and vitamin C ) for the most part in the food and are hardly transferred to the cooking liquid compared to cooking. Steam cooking can be carried out in steamers specially designed for this purpose , in combination steamers , but also in a saucepan with a sieve or perforated insert provided for this purpose . The insert holds the food in the steam space above the cooking liquid. The cooking temperature is 100 ° C at ambient pressure. When steaming in a pressure cooker , which also has a sieve or perforated insert for this purpose, the cooking temperature rises to 120 to 125 ° C.
Cooking with very little liquid is called stewing. A little fat is often added. The liquid often comes from the food itself.
A special form of steaming is the glazing of sugary vegetables . The sugars are given off by the vegetables ( carrots , chestnuts , etc.) and, towards the end of the cooking time, result in a syrupy liquid which, when swirled, becomes a glaze coating on the vegetables.
Cooking or poaching (e.g. lost eggs ) is carried out at 75 to 95 ° C. The food is left to soak in hot but not boiling water. Sensitive foods ( eggs , tender vegetables) should be cooked more gently than when cooking. An egg mass up to max. Heating to 85 ° C is known as peeling off to the rose . Blown on the back of a wooden spoon, it then spreads out in waves, which is supposed to be reminiscent of a rose. In the case of an ice cream mass (e.g. for the production of cream ice cream , Bavarian cream ...), it must be ensured that the temperature of 85 ° C is not exceeded, otherwise the proteins contained will clump too much and separate from the mass, which causes the Mass loses its bond. As a result, the mass also loses its suppleness and a gritty feeling develops on the tongue when it is consumed.
Microwave ovens heat water-containing foods by stimulating the water molecules using electromagnetic radiation of a suitable frequency, i.e. the microwave . Since the radiation has a depth of penetration that depends on the food being cooked and is therefore finite, heating begins on the outside of the food. The effect is similar to that of cooking due to the closed cooking space and the resulting high humidity .
Pressure cooking is cooking or steaming in a tightly closed pot. At normal air pressure, water boils at 100 ° C. Further supply of heat causes steam to escape, but no further increase in temperature.
With the pressure cooker , the water vapor is retained and builds up an overpressure. This allows water to be heated up to around 120 ° C. The higher cooking temperature shortens the cooking time.
The temperature is only increased by around 20 ° C, but the starch gelatinization and protein coagulation only begin at around 70 ° C, so that the cooking process is significantly accelerated.
Low temperature cooking
Low-temperature cooking means gentle long-term cooking (and keeping it hot) with small temperature differences of 20 to 30 ° C between the appliance and the desired core temperature of the food, for example roast beef - cooked at around 65 ° C to 80 ° C - is particularly tender and also only suffers little weight loss from dehydration.
With vacuum cooking (French sous-vide ), the food to be cooked is packed raw and seasoned in a plastic bag suitable for food. The bag is vacuum- sealed and sealed with a vacuum sealer. This process reduces oxidation and evaporation of volatile aromas of the food during the subsequent cooking in the water bath. The vacuum bag is usually cooked at low temperatures (approx. 65–80 ° C), which modern thermostats can be maintained very precisely over long periods of time and thus allow a uniform and reproducible result.
Dry cooking techniques
As dry cooking techniques is called cooking techniques without the addition of water, for. B. Frying (contact), baking ( convection ) or deep-frying (fat). Due to the comparatively high temperatures and the absence of water, a crust is formed on the food . Typical reactions are the Maillard reaction and, in parallel, the caramelization of the carbohydrates contained in the food . From 180 ° C also begin Verkohlungsprozesse .
Roast in the pan
Roasting serves (in addition to simple heating) for the formation of flavorings through the Maillard reaction when the crust is formed. In contrast to cooking, the direct supply of heat through the bottom of the pan can reach temperatures of well over 100 ° C, theoretically several hundred degrees with uncoated pans.
Basically, the pan is heated first. In order to achieve a heat seal between the pan surface and the food, some fat or oil and then the food are added. Therefore, the addition of fat or oil is necessary even with non-stick pans. Due to the heat, the proteins on the side facing the pan bottom coagulate much faster than the rest, which is why the food is usually turned over.
The theory previously accepted and made known by Justus von Liebig that the outer layer would hold back the juice inside through a “seal” has now also been refuted in terms of food chemistry. In some cases, for example - especially with light pressure - you can see the escape of meat juice from the coagulated surface. Even if it is not possible to speak of a complete seal, the loss of juice is at least somewhat less than on a raw surface.
Due to the comparatively very strong heat shock, however, there is an extremely high risk that the meat will become tough and dry out, which is why valuable pieces of meat are only seared very briefly in professional kitchens and otherwise carefully cooked to the end in the oven.
Anhydrous fats that are low in accompanying substances are used for frying. Fats containing water splash and therefore cannot be heated sufficiently. Accompanying substances reduce the temperature stability ( smoke point ), above which the fat decomposes into substances that are often harmful to health. The heated fat ensures even contact between the food and the pan, even if the surface is irregular, and often affects the taste.
When sautéing , the food is first cut into small pieces and then placed in a special pan over high heat with little fat. Only enough food may be added that everything can lie on the pan base. By swiveling the pan, the food is turned and seared on all sides. Because of the high temperatures, butter is not suitable for sautéing. Usually after sautéing, just before serving, a little butter is added to improve the taste. Sauteing is similar to stir-frying in a wok , a method from East Asia.
Roasting and baking in the oven
Before roasting meat in the oven , it is usually seared at a very high temperature and then further cooked at a temperature that varies depending on the thickness and type of meat, often between 70 and 120 ° C. When preparing cakes, bread and other baked goods, there is no need to fry and the temperatures are usually significantly higher at 140 to over 200 ° C.
Direct grilling uses radiant heat to cook at a very high temperature by placing the food above, below or between two heat sources, which helps to create a crust very quickly. When grilling properly, most of the juice remains in the food. The edge is often smeared with oil or fat to keep it from drying out.
With indirect grilling, the food is cooked in a closed container at low temperatures. No crust forms on the surface of the food.
The main advantage of indirect grilling is that even thick food is cooked evenly because the heat has enough time to penetrate inside. In addition, the juices are retained and there is no need to turn the food. In addition, no fat can drip onto the charcoal and so no harmful substances can be produced when it evaporates. The disadvantage is that the cooking time is considerably longer. The taste can be influenced by adding moist pieces of wood to the charcoal; Placing a container with water or beer in the grill makes the food particularly juicy.
In a kettle grill, the food is placed in such a way that the heat reaches the grill food indirectly through reflection on the inside of the kettle grill. In a smoker, on the other hand, the grilled food is cooked in hot smoke, see barbecue .
Deep-frying is cooking in fat floating at around 140 to 180 ° C. The hot fat surrounds the food on all sides. Only highly heatable fat may be used. During deep-frying, some of the fat enters the food, which on the one hand changes the taste, usually improves it, and on the other hand is not always desirable for nutritional reasons. When deep-frying, the introduction of the frozen goods (example: industrially prepared French fries ) and the evaporation of water result in a considerable loss of heat, which leads to a sudden reduction in the temperature of the hot fat. The evaporation of water can also lead to a greater weight loss, which is only partially compensated for by the penetration of the fat. A portion of the deep-frying fat penetrates the deep-fried food during deep-frying, but four times as much penetrates the deep-fried food when it cools down, if the water vapor condenses in the deep-fried food and leaves a vacuum. The amount of frying fat depends on the type of food being fried, the surface-to-mass ratio of the food being fried and the design of the draining process. French fries, for example, contain about 6–12% deep-frying fat.
Roasting is the dry, fat-free heating of plant-based foods in order to remove moisture from them, to change their taste or to color them darker. The food is heated to up to 300 ° C, with strong-tasting aromas and bitter substances that stimulate the appetite . Are roasted z. B. nuts , coffee and cocoa beans , grain , malt or chickpeas . One of the flavoring chemical reactions that can occur during roasting is the Maillard reaction .
When cooking or cooking time is time referred to a food cooking, in order then for consumption palatable and digestible to be. The cooking time depends on the cooking appliance used, the cooking method used and the food to be cooked. At the same time, preferences play an important role with regard to the definition of “a food is cooked”.
Cooking levels for meat
|heavily bloody, raw, blue||bleu, cru||blue, rare, raw||≤ 45 ° C||The meat is raw inside. It has a brown, thin crust and gives way under pressure. The meat juice that comes out is red. The proteins are about to denature . Finger pressure test: the meat is completely elastic and does not have a firm consistency.|
|bloody, english||saignant||rare, underdone||48 - 52 ° C||The core of the meat is still slightly juicy and pink on the outside. It has a brown, crispy crust. The core is about 75% red. Finger pressure test: The meat is largely elastic and has a poor firm consistency.|
|light pink, pink||à point , anglaise||medium rare||53 - 60 ° C||The meat is pink throughout, gives way to pressure and has a brown, crispy crust. Typical cooking level for beef steaks. The core is about 50% red. Finger pressure test: The meat is slightly elastic and has a firmer consistency.|
|halfway through||légèrement rosé, demi-anglaise||medium||60 - 65 ° C||The meat has only a light pink core, the meat juice is pink. Finger pressure test: the meat is hardly elastic and has an almost firm consistency.|
|cuit||medium well||65 - 69 ° C|
|by||bien cuit||well done||70 ° C and higher||The meat is completely cooked through. This cooking level is for microbially susceptible foods such as B. Poultry is absolutely necessary for hygienic reasons . Beef or lamb steaks become dry and tough in this cooking setting. Finger pressure test: the meat is not elastic and has a firm consistency.|
To measure the core temperature of the piece of meat, a roast thermometer is inserted into the piece of meat so that the probe tip is in the middle of the thickest point. The core temperatures in the table correspond to the temperature of the meat at the time of serving. Accordingly, the temperature equalization to which the meat is subjected when standing should be taken into account . For example, to serve a beef fillet as saignant , it is cooked in a convection oven at 180 ° C and taken out of the oven at a core temperature of 38 ° C. When standing in a warm environment, the core temperature then rises to 48 ° C. If the oven temperature is only 20 ° C above the cooking level to be achieved, it is called low-temperature cooking . In this case there is only a slight temperature compensation. The meat is cooked through until it reaches the desired temperature.
- Cooking times table, Koch-Wiki
- Optimal Frittieren - Recommendations of the German Society for Fat Science (PDF file; 1.26 MB)
- Better bloody than well done. Anyone who eats large amounts of long and spicy seared meat risks a bladder tumor. On: Wissenschaft.de from April 19, 2010
- Point 7.6.1. Gartechnicken at hotelfach.de
- Dr. rer. nat. A. Täufel, Dr. agr. L. Tunger, prof. dr. agr. habil. m. Zobel (Ed.): Food Lexicon . VEB Fachbuchverlag Maxim Gorki, Leipzig, p. 311 .
- Wolfgang Frede: Handbook for food chemists: Food - Commodities - Cosmetics - Feed . Springer-Verlag, 2010, ISBN 978-3-642-01685-1 ( google.de [accessed on February 20, 2018]).
- E. Schlich, M. Schlich: Cooking methods for plant-based foods and their influence on micronutrients - Part 1. In: ErnährUmschau. (60), 8, 2013, pp. S31-S34.
- E. Schlich, M. Schlich: Cooking methods for plant-based foods and their influence on micronutrients - Part 2. In: ErnährUmschau. (60), 9, 2013, pp. S35-S38.
- Nathan Myhrvold , Chris Young, Maxime Bilet: Modernist Cuisine: The Art and Science of Cooking. Volume 3, The Cooking Lab , 2011, ISBN 978-0-9827610-0-7 , pp. 89ff.
Expert on the topic: (In five parts)
- Tender meat - scientifically explained
- Cook meat gently
- Tender meat on the plate ( Memento of the original dated December 2, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- Upgrade meat when cooking low ( Memento of the original from February 10, 2008 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
- Cook meat gently
- Hans-Albert Kurzhals (Ed.): Lexicon of food technology. 1st edition. B. Behr's Verlag , Hamburg 2003, ISBN 3-86022-973-7 , p. 939.
- Aliza Green: Field Guide to Meat . Quirk Books, Philadelphia, PA 2005, ISBN 1-59474-017-8 , pp. 294-295 .