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Food Chemistry. Chapter 17 in Green / Damjii F.1: Food Groups. Homework. Read F1 – Food Groups - pp. 475-476 Do Qs 1-6 (on p 490) and/or take notes on the sections Participate in interactive lecture in class and take study notes. F.1: Food Groups.
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Food Chemistry Chapter 17 in Green / Damjii F.1: Food Groups
Homework • Read F1 – Food Groups - pp. 475-476 • Do Qs 1-6 (on p 490) and/or take notes on the sections • Participate in interactive lecture in class and take study notes
F.1: Food Groups • F.1.1: Distinguish between a food and a nutrient
Food • Any substance we deliberately take into our mouths and swallow. • Any natural or artificial material intended for human consumption • Contains one or more nutrients
Nutrient Component of food that is used by the body to • provide energy • Aide in growth and/or repair of tissue A lack of these nutrients may cause • malnutrition
Major Nutrients • Lipids • Carbohydrates • Proteins
Other Nutrients • Vitamins • Minerals • Water
F.1: Food Groups • F.1.2: Describe the chemical composition of lipids (fats and oils), carbohydrates, and proteins.
Major Nutrient - Lipids Fats and Oils are… • Source of Energy • Vital in constructing cell membranes
Major Nutrient - Lipids • Contain C, H, O • Esters of glycerol and 3 fatty acids • Aka triglycerides http://www.ilri.org/infoserv/webpub/fulldocs/ilca_manual4/images/fig_pg9.gif
Triglycerides “R” group can be… • SATURATED (no double or triple bonds) • Tend to be SOLIDS at room temperature • Tend to come from animal products • “Fat” • Unsaturated (has one double or triple bond) • Tend to be LIQUIDS at room temperature • Tend to come from plant material • “Oil” • Polyunsaturated (has multiple double or triple bonds) Nature of “R” group determines physical and chemical properties.
Which of these lipids is saturated? Unsaturated? Polyunsaturated? B A C
Which of these lipids is saturated? Unsaturated? Polyunsaturated? Citations for images on previous slide http://wpcontent.answers.com/wikipedia/commons/thumb/b/be/Fat_triglyceride_shorthand_formula.PNG/220px-Fat_triglyceride_shorthand_formula.PNG http://www.biology.lsu.edu/introbio/Link2/triglyceride.gif http://www.chm.bris.ac.uk/motm/ethylacetate/triglyceride.gif
What about this one? http://www.bio.miami.edu/~cmallery/150/chemistry/c4x5fatmolecule.jpg
Which of these lipids is saturated? Unsaturated? Polyunsaturated?
Major Nutrient - Carbohydrates Carbohydrates are… • Source of Energy • Vital in cell construction
Major Nutrient - Carbohydrates • Empirical Formula = CH2O
Major Nutrient - Carbohydrates • Simple Carbohydrates • Monosaccharides = (CH2O) n>2 = simplest carbohydrates Ex: Glucose fructose
Major Nutrient - Carbohydrates • Disaccharide – formed from condensation of 2 monosaccharides.
Major Nutrient - Carbohydrates • Polysaccharides – formed from condensation of many monosaccharides. Starch
Major Nutrient - Proteins Proteins … • build up, maintain, and replace tissues (muscles, organs, imunne system) in your body • Primary component in hair and nails • make enzymes, hormones, and other body chemicals • building block of bones, muscles, cartilage, skin, and blood.
Major Nutrient - Proteins • Contain C, H, O, and N… • And some contain P and S • Are polymers of amino acids • 22 important amino acids • 13 body makes, 9 are “essential”
Major Nutrient - Proteins The R groups represent side chains of the amino acids involved and can be the same or different.
Food Chemistry Chapter 17 in Green / Damjii F.2: FATS AND OILS
Homework (Done in advance!) • Read F2 – Fats and Oils - pp. 476-477 • Do Q 7-11 • on p 491
F.2: Fats and Oils • F.2.1: Describe the difference in structure between saturated and unsaturated (mono- and poly-unsaturated) fatty acids Remember… 3 molecules of fatty acids react with 1 molecules of glycerol to form a lipid
F.2: Fats and Oils • F.2.2: Predict the degree of crystallization (solidification) and melting point of fats and oils from their structure, and explain the relevance of this property in the home and in industry.
F.2: Fats and Oils • Melting point and hardness (degree of crystallization) depend on • Length of hydrocarbon chain • Longer chain = greater molar mass = more vdW forces = higher mp • Degree of unsaturation • More double bonds = crooked chains = less contact = fewer vdW forces = lower mp • Cis or trans conformation • more cis = more crooked chains = less contact = fewer vdW forces = lower mp • more trans = less crooked chains = more contact = more vdW forces (compared to cis) = higher mp
Triglycerides • SATURATED (no double or triple bonds) • Tend to be SOLIDS at room temperature • Tend to come from animal products • “Fat” • Examples: • Coconut oil • Butter • lard
Triglycerides • Unsaturated (has one double or triple bond) • Tend to be LIQUIDS at room temperature • Tend to come from plant material • “Oil” • Examples • Olive oil • Canola oil • Peanut oil • Polyunsaturated (has multiple double or triple bonds) • Example • Sunflower oil • Corn oil • Fish oil