The thickening of the gravy used in most of the starch and water stirred into the starch paste at high temperatures, has a certain viscosity, has a strong ability to absorb water and absorb odors. General dishes, the soup is thicker than the dish flavor, and there are many inorganic salts, vitamins and other nutrients in the soup. Thickening will make the soup wrapped in raw materials to reduce the loss of nutrients in food. It is particularly worth mentioning that the thickened dish is suitable for people with stomach problems to eat. Because starch is condensed by a number of glucose molecules into polysaccharide polymers, it can act with gastric acid, the formation of colloidal liquid, attached to the stomach wall, forming a protective film to prevent or reduce the direct stimulation of gastric acid on the stomach wall, to protect the gastric mucosa. Generally speaking, thickening to master the time, should be carried out when the dishes are nine mature. Too early will make the gravy scorched; too late is easy to make the dish heat time is long, lose the taste of crisp. Second, the thickening of the dishes with oil can not be too much, otherwise the gravy is not easy to stick in the raw materials. Third, the dishes should be appropriate soup, soup too much or too little, will cause the gravy too thin or too thick, affecting the quality of the dish. Thickening with starch, mainly mung bean starch, potato starch, wheat starch, etc., these starches are absolutely safe for human health, can be consumed without fear. Due to the starch hygroscopicity is strong, easy to mold, mold, do not eat, which will produce a can lead to liver cancer aflatoxin. In addition, some dishes do not need thickening, such as the taste of fresh dishes (such as fried bean sprouts), dishes containing more collagen (such as braised hooves), need to join the sauce, sugar dishes (such as fish in sauce), containing more starch dishes (such as fried shredded potatoes) and so on. Thickening How to thicken Thickening The academic concept of thickening is: with the help of starch in the case of pasteurization in the presence of heat, has the characteristics of water absorption, adhesion and smooth moist. When the dishes are close to maturity, will be adjusted to the powder sauce into the pot, so that the marinade thick, thick, increase the adhesion of marinade on the raw materials, so that the powder and concentration of the dish soup to increase and improve the color and flavor of the dishes. Thickening starch, also known as powder, is a polysaccharide polymer condensed from multiple glucose molecules. Cooking starch, mainly mung bean starch, potato starch, wheat starch, diamond, lotus root starch and so on. Starch is insoluble in water, in and water heated to 60C, then paste into a colloidal solution. Thickening is to take advantage of this property of starch. Mung bean starch is the best starch and is generally seldom used. It is made from mung bean water up grinding, precipitation and become, it is characterized by viscous enough, small water absorption, color white and glossy. Potato starch is the starch commonly used in the family at present, which is made by potato grinding, kneading and precipitation, and is characterized by sufficient viscosity, fine texture, white color, and better luster than mung bean starch, but poor water absorption. Wheat starch is wheat bran after washing gluten precipitation or made of flour, characterized by white color, but the luster is poor, the quality is not as good as potato starch, thickening is easy to precipitate. Sweet potato starch is characterized by strong water-absorbing capacity, but poor viscosity, no luster, color dark red with black, by the fresh potato grinding, kneading and washing, precipitation and become. In addition, there are corn starch, diamond, lotus root starch, water chestnut starch and so on. Whether thickening is appropriate, the quality of the dish has a great impact, so thickening is one of the basic skills of cooking. Thickening is mostly used for simmering, sliding, frying and other cooking techniques. These cooking methods **** the same point is the fire quickly, there is this method of cooking dishes, basically not with soup. However, due to the cooking of certain seasonings and raw materials itself out of water, so that the dish to see an increase in soup, through the thickening, so that the juice thick and attached to the surface of the raw material, so as to achieve the dishes glossy, smooth, tender and fresh flavor. Thickening is generally used two types. One is the starch juice and seasonings, commonly known as "juice", mostly used for fire power, fast speed of simmering, popping and other methods of cooking dishes. One is simply starch juice, also known as "wet starch", mostly used for general fried dishes. Pouring juice is also a kind of thickening, also known as thin gravy, glazed gravy, mostly used for simmering, burning, steak and soup dishes. According to the cooking method and the characteristics of the dishes, there are generally the following kinds of gravy usage: 1. package gravy is generally used for stir-fry method of cooking dishes. Powder sauce is the thickest, the purpose is to make the gravy all wrapped to the raw materials, such as shredded pork with fish, fried cashews, etc. are used to wrap the gravy, after eating the dishes, the bottom of the plate basically does not leave the marinade. 2. paste cross generally used for simmered, slippery, stewed, braised method of cooking dishes. Powder than the package gravy thin, the use of soup dishes into a paste, to achieve soup and vegetables fusion, taste smooth and soft, such as: sweet and sour pork and so on. 3. flow thickening powder thinner, generally used for large or whole dishes, its role is to increase the flavor and luster of the dishes. Generally in the dishes on the plate, and then the pot of marinade heating thickening, and then poured on the dishes, part of the dip in the dishes, part of the state of the glass, after eating the plate can be part of the remaining juice. 4. milk soup gravy is the thinnest gravy, also known as thin gravy. Generally used for braised dishes, such as: spicy tofu, shrimp potpourri and so on. The purpose is to make the dish soup thicker to achieve the color and fresh requirements. To thicken, need to master a few key issues: First, master the thickening time, generally should be nine mature dishes, too early thickening will make the marinade scorched, too late thickening easy to make the dish heat long time, lose the crispy, tender taste; Secondly, thickening the dishes with oil can not be too much, otherwise the marinade is not easy to stick in the raw materials, can not achieve the freshness, beauty and shape of the purpose; Thirdly, the dish soup to be appropriate, too much or too little soup, will cause the thickening of too thin or too little. caused by the gravy is too thin or too thick, thus affecting the quality of the dishes; Fourth, when thickening the sauce with simple powder, you must first taste the dishes, color and lustre, and then dripping into the wet starch thickening, in order to ensure that the taste of the dishes is beautiful and colorful. Starch hygroscopicity, there is the absorption of odor characteristics, so attention should be paid to storage, should be moisture-proof, mildew-proof, anti-odor. Generally to room temperature 15C and humidity below 70% of the conditions are appropriate. Cooking and the requirements of the oil gravy, that is, in the dish is ripe after thickening, and then dripping into a variety of different flavored oils, so that it is dissolved in the gravy or attached to the gravy. The dishes play an aroma, freshness, color, shine effect. The use of the two should be combined, according to the taste and color requirements of the dishes, dripping into different colors of cooking oil, such as: chicken oil (yellow), chili oil (red), tomato oil, sesame oil, pepper oil and so on. When dripping oil should pay attention to, must be in the gravy cooked dripping, in order to make the gravy bright oil Ming. One time refueling can not be too much too fast, otherwise there will be the phenomenon of oil secretion. Due to different cooking methods, the method of refueling is also different. General stir-fry, stir-fry dishes, more in the ripe side of the spoon while dripping into the oil. Dry roasted dishes, dishes are out of the spoon, the remaining juice in the spoon into the oil laxative open, poured on top of the dishes. After joining the gravy in oil, stirring and overturning not too fast, to avoid separation of oil gravy.