Define the functional properties of hydrocolloids
The hydrocolloids not only have the functional properties but also have nutritional characteristics. Most polysaccharide gums are not metabolized in the upper digestive tract but pass into the large intestine with little or no change. Some sugars get converted to short chain fatty acids that are eventually absorbed and metabolized. However most gums function as soluble dietary fibre and provide negligible calories. For this reason, these have been particularly useful in recent years as zero-calorie fat replacers, especially in high fat systems, such as dairy products and salad dressings. Gums are used in low calorie foods to thicken or improve body, cover flavours, provide bulk, aid in carbonation retention and control ice crystal formation.