Functions and Purpose of Starch
- Flour is often the main ingredients in many food products amd call it the bulk ingredient. The starch forms the main structure of the product. Examples include biscuits, cakes and pastry.
- Raw starch tastes floury and therefore needs to be cooked, an example is plain flour. When the starch is heated in hot liquid, the walls of the starch become soft and allow liquid to pass slowly through them. This makes the granules swell until they burst. This process is called gelatinisation.
- Starch particles do not dissolve in liquid. Instead they form something called suspension.
- If the liquid is not stirred, the starch granules sink to the bottom and stick together and start to form lumps.
- When heated at 60 degrees, the starch particles begin to absorb the liquid and swell.
- At 80 degrees the particles will have absorbed five times their volume.
- Gelatinisation is when the liquid reaches 100 degrees.
- When the sauce cools it goes even thicker.
- Some examples are wheat flour is used with fat and milk to make white sauce.
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