Dextrins are carbohydrate chains of glucose molecules made by heating starches such as cornstrarch, potato starch, or tapioca. 

Dextrins have a variety of uses in food processing.  They hold water and are used as a thickener in many sauces and gravies and as an expander in bakery goods.  They are also used as a foam stabilizer in brewing, and as a mildly sweet sugar substitute. 

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