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Chapter 15. Carbohydrates. Carbohydrates. Most abundant organic (carbon containing) molecules on earth Made of C (carbo), H, and O (hydrate-water) Includes starches, sugars, and fibers Provides energy (4 cal/gr)for the body
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Chapter 15 Carbohydrates
Carbohydrates • Most abundant organic (carbon containing) molecules on earth • Made of C (carbo), H, and O (hydrate-water) • Includes starches, sugars, and fibers • Provides energy (4 cal/gr)for the body • Produced by plants during photosynthesis plants change CO2 (from the air) and H2O • (taken up by roots) into carbohydrate and oxygen (chlorophyll must be present • 6CO2 +6H2 O + Energy--->C6H12O6 + 6O2 • Carbon Water sunlight Glucose oxygen • Dioxide • Glucose basic sugar unit-produced first, then other sugars, then starches (so a younger plant is sweeter
Sugars:Sweet crystalline carbohydrate • Saccharide • Simple carbohydrates • 1.Monosaccharides (single sugars) • Glucose (main sugar in blood) • Fructose(fruits(sweetest) • Galactose (milk product • 2.Disaccharide-(2 monos bonded together) • Sucrose(table sugar) • Lactose (made in mammary glands) • Maltose (cereals)
Sugar in processed food 1tbs=2tsp 1c = 7tsp 12oz=8tsp 1/2c.=3tsp 2oz=8tsp 1tbs=1tsp
Glucose blood sugar • Main Carbohydrate in the body • Source of energy • Affects health and functioning of all the cells in the body • Prime function is provide the brain and nervous system with energy • Level of glucose provided to the brain is critical to the ability to think and function • Homeostasis is bodies ability to regulate itself
Hypoglycemia-too little glucose in the blood. Brain unable to get enough glucose symptoms are dizziness, weakness, and nausea • Hyperglycemia- too much glucose in the blood-causes pancreas may not secrete insulin normally,cells not responding to insulin secreted
Diabetes • Diabetes-body that cannot regulate blood glucose normally • Type 1 Diabetes-pancreas makes little or no insulin occurs in children or young adults-must take insulin everyday • Type 2 diabetes-not enough insulin is produced in the pancreas occurs in people over 40. 90% of all diabetics is this type • Regulated by diet and exercise
Starch • Polysaccharide-10 or more Monosaccharides chemically linked together • Polymer-large molecule formed when small molecules of the same kind join together to form chains (polymerization) • Starches and fibers-polysaccharide (complex carbohydrates) • Carbohydrate made from a chain of sugar molecules—polymer of sugar
Structures of starch molecules • Linear-amylose(rice, wheat flour) • Branched-amylopectin (potato, tapioca) • Amylose best thickening agent
Starches: available complex carbohydrates • Straight chains of glucose= amylose Slightly to moderately branched chains of glucose = amylopectin and will set up a gel by trapping water
Cooking with starch • Gelatinization-process of starch molecules forming hydrogen bonds • Forms a paste (thickened starch mixture) • Sol-fluid paste • Gel-solid paste • Viscosity –thickness of a mixture(resistance to flow) • Retrogration-the thickening of starches as they cool • Syneresis-water leaking out of a paste
Fiber • Cellulose-polysaccharide)cannot be digested • Absorbs H2O to prevent constipation • Reduces transit time of food through intestine • Binds toxic foods (may help prevent cancer) • Average American diet 4 g fiber • Developing nations 30g fiber
Diabetic Diet • Little protein/fat • More complex (starchy)carbos • More fiber • Little salt • Eat regularly • exercise
Hydrolysis of Sugar • Glucose + Fructose>sucrose +Water • Reverse process is called Hydrolysis • (splitting a compound into smaller parts by adding H2O) • Sucrose + Water >Glucose + Fructose • Disaccharide>2monosaccharides from which it was formed
Hydrolysis to occur: • Enzyme invertase (sucrase) • Acid • Heat • Also called inversion (inverted sugar formed)
Carmelization • Browning reaction • High temperature • Low or high PH • As sugar is heated, dehydration occurs (loss of water) • Water leaves sugar molecule-new molecules, high concentration of carbon-brown color • Sucrose carmamelizes at 170°
Sweetness and Solubility • Sweetest Most Soluble • Fructose honey(fructose & Glucose) • Sucrose • Glucose • Galactose • Maltose • Lactose
Crystallization of Sugar • Crystal-solid in which ions are arranged IN A REGULAR REPEATING PATTERN • Crystalline Candies-(crystals formed from a sugar solution) • Fondant, fudge, divinity
Sugar Solutions • Sugar-very soluble • Solubility increases as temperature increases • To get a lot of sugar to dissolve, heat the solution, if it is then cooled carefully (without agitation) you will have a supersaturated solution (contains more dissolved solute then normal at that temperature)
This is how candy is made! • Step I • When making candy, the supersaturated solution is cooked to a certain concentration ( as solution cooks, H2O evaporates) which is measured by temperature • Candy making success depends on temperature!!!!!!!!!!!!!
Step II • Controlling the size of the crystals that separate from the solution smaller the crystal better the candy • Affected by: interfering agents, agitation, ripening