Whipped egg whites turn into solid foam by the action

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-Whipped egg whites turn into solid foam by the action of heat on egg proteins Carbohydrates - Occur in foods such as sugar and starches, digestible carbohydrates contribute to 4 calories(kilocalories) of metabolized energy per gram -Efficient, generally inexpensive source of energy and contribute to 50% of our caloric intakeMonosaccharides-Found in foods such as glucose (70-90), fructose (140), galactose(60)-Simple sugars as their main function is their ability to impart a sensation of sweetness Disaccharides - Sucrose, lactose and maltose are disaccharides and differ in solubility, sweetness, and other propertiesSucrose – glucose + fructose (100)-Food industry likes to invert sugar in place of sucrose because invert sugar is sweeter than sucrose per unit weight -Invert sugar is produced by hydrolyzing sucrose with an enzyme (invertase) or acid to produce glucose +fructose Lactose – glucose + galactose (10-20)-Cow milk: 4 - 5%, human milk: 6 - 8%-Hydrolysis of lactose found in dairy products is catalyzed by lactase -Breaking down lactose increases sweetness and can be fermented by lactic acid-producing bacteria intolactic acid (acidulant and preservative agent in yogurt, cheeses)Maltose – 2 glucose (2)-Obtained when starch is hydrolyzed by amylase or heating with dilute acid -Can be further hydrolyzed by maltase into D-glucose units which are enzymatically isomerized by glucose isomerase to produce liquid syrup of 42% fructose known as high fructose corn syrup (42% fructose, 52% glucose, 6% starch)Functional Properties of Simple Sugars in Foods-Sugars are used as a sweeteningpowder-Determined by their molecular structure and interaction with sensory receptors on tongue -Sweetness has no relation to caloric contribution -Sugars produce bodyand mouth feelwhen incorporated into foods at high concentrations to affect viscosity of food product-Production of hot supersaturated sugarsolutions with controlled crystallization during cooling is the basis of formation of many hard candy products, toffees and related products-Sugars are readily soluble in waterbecause they contain many hydroxyl (OH) groups, which form hydrogen bonds with water. Solubility of sugars increases as the temperature of water increases- This property is used to produce syrups of varying concentrations for various uses (e.g. pancake syrup, concentrated syrups for use in food processing, cooking or confections) -Sugars can be crystallizedfrom solution when water is evaporated. This is the basis of production of table sugar (sucrose) from the juice extracted from sugar cane and sugar beets-Sugars, in sufficiently high concentration, can be used to inhibit growth of undesirable microorganisms. They function as a preservativeby binding water needed by the microorganisms-Sugars are fermentedby microorganisms with the concomitant production of acids and/or alcohol as well as flavouring compounds. This is the basis for production of fermented foods and ingredients obtained by means of microbial fermentations-Sugars caramelizewhen exposed to high temperatures

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