Starch is mainly made from foods with high starch content, such as beans. If it is used in cooking, it needs to be mixed with water and poured out before the dish is ready to make it sticky. It makes sense for people to use starch in cooking. People's taste is related to the physical state and chemical composition of food. Physical state such as humidity, viscosity, temperature, tenderness and other factors will affect the taste of food.
When food comes into contact with human tongue, it has different tastes due to the difference of cold, heat and contact time. For example, the dish of fried belly with oil tastes fragrant, crisp, tender and thick when it is hot, which increases the viscosity, makes the dish stay on the tongue for a long time, and increases the contact surface between the dish and the tongue, so it feels thick and long.
chemical property
Many chemical properties of starch are similar to glucose, but because it is a polymer of glucose, it has its own unique properties. In production, two important starch deep-processing products can be obtained by changing starch molecules by using the chemical properties of starch.
The first category is the hydrolysis products of starch, which are products with different DP obtained by degrading starch molecules by using the hydrolysis properties of starch. The α- 1, 4-glycosidic bond and α- 1, 6-glycosidic bond of starch are hydrolyzed under the action of catalysts such as acid or enzyme, and many products such as dextrin, oligosaccharide, maltose and glucose can be produced.
The second kind of product is modified starch, which is produced by the chemical reaction between starch and some chemical reagents. Under certain conditions, alcohol hydroxyl groups on C2, C3 and C6 of glucose residues in starch molecules can undergo chemical reactions such as oxidation, esterification, etherification, alkylation and crosslinking, resulting in various starch derivatives.