Gelatinisation
Gelatinisation is the thickening of starch causing a permanent suspension*. Starch gelatinization is a process of breaking down the intermolecular* bonds of starch molecules in the presence of water and heat, allowing the hydrogen bonding* sites to engage more water. There are many physical changes that occur throughout gelatinisation. These include changing in viscosity*, flavour and colour. There are three factors that affect the physical and chemical reactions in gelatinsation. These are temperature, stirring and the ratio between flour to milk. Gelatinisation occurs when starchy foods are cooked with water. The starch loosens, absorbs some water, and eventually can soften enough to lose its shape. Meat has different types of muscle fiber and ‘tough’ meat has connective tissue that makes it chewy. If you cook the meat long enough, the connective tissue will gelatinise.
Gelatinisation in this recipe and Evaluation
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In this recipe gelatinisation takes place with in the white sauce. The ingredients taking part in gelatinisation are
Butter Flour Milk The butter becomes the liquid and when flour is added and heated, the mixture thickens. The milk is only a part of the gelatinisation process as it holds the heat better. Gelatinisation plays a large roll in the white sauce aspect of this recipe. It is important that when you make the sauce that you are not over cooking the roux mixture. Also it is crucial that you don't stir too quickly as it will get too much air into the roux mixture. |
Other recipes
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Gelatinisation takes place in many other recipes. Some of these include
Meringue pie Gravy Jelly Beef stir-fry (covered later on) In these recipes gelatinisation plays a large roll. |
Physical Changes
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In this recipe gelatinisation increases the viscosity* of the sauce when it was heated up.
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