Denaturation & Coagulation
Denaturation is the permanent alteration* of the protein structure by heat, acid or agitation. It breaks the chemical bonds that holds the amino acids* together. Protein denaturation is when the three dimensional structure of a protein is disrupted by heat or acid. In other words, the protein is changed or destroyed. Coagulation is the setting of protein when heat or acid is added. An example of this is raw egg to cooked egg. Coagulation is easily seen in cooking an egg. The process where the ‘clearish’ egg white turns actually white under heat is protein coagulation. Meat changes texture as it cooks due to protein coagulation. It goes from raw which is chewy and a lot of moisture is held in the fibers to well done where it’s a bit more like dry leather.
Denaturation & Coagulation in this recipe and Evaluation |
In this recipe denaturation takes place in the marination process and the slicing of the meat. Coagulation takes place in the cooking of the meat.
Denaturation and coagulation are really important for making the recipe work. Gelatinisation is also important as it makes the sauce but a large part of beef stir fry is the marinating which is denaturation and the cooking of the meat which is coagulation. When cooking this recipe you must make sure that you do not cross contaminate* and that you do not over cook the foods. The vermicelli must have water poured over it and not sitting in the hot water as it will burn it. |
Other recipes |
Denaturation & coagulation takes place in many other recipes. Some of these include
Cooking of egg Hamburgers Pizza in all these recipes denaturation and coagulation play a major part. |
Physical Changes
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The physical changes in this recipe are more noticeable then in most other recipes. The meat browns as it takes part in coagulation and it changes flavour when it is marinating.
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