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Fat Structure

Fat Structure

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Fat Structure

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  1. Fat Structure Fatty acids are either saturated, monounsaturated (contain one C=C double bond) or polyunsaturated (contain two or more C=C double bonds) Saturated fatty acids stack closely and are more solid. Unsaturated fatty acids are more fluid. “Hydrogenating” unsaturated fatty acids makes them more rigid.

  2. Cis and trans hydrogens

  3. Trans fats “look” more like saturated fats. Trans fats “look” more like saturated fats. Polyunsaturated > monosaturated “Partially hydrogenated” fats. “Attempt” to hydrogenate 4 cis double bonds succeeds with 2, leaves one alone, creates one trans double bond.

  4. Talk Show Schlock – Apples, arsenic, Alar Timely vs “on topic”

  5. Transition: Top Ten Lessons I Learned In College 10. Success is 1% inspiration and 99% cramming the night before the exam. 9. Roommates can be pretty harsh if you're still sleeping with your Big Bird doll. 8. Laughing at the professor’s jokes brings up the curve. 7. The best way to learn biology is in the woods behind Heylar House. 6. On Microsoft Word, if you drag down the format window and click on paragraph, adjusting the line spacing can make your papers look a lot longer. 5. Do your laundry every six months, whether you need it or not, (or take it home and have Dad do it.) 4. Do I have to think of another? 3. Um...sorry, I'm drawing another blank. 2. My parents wasted about 80 grand.1. If you major in some lightweight field, goof off and get bad grades, you could become rich like that dropout Bill Gates.

  6. Sugars, Starches, Gums and Fibers

  7. Outline • Video • Uses in foods • Structure and function • “Artificial Sweeteners” Aspartame Smear • Starches, Pectins and Gums • Fiber and Diet • Metabolism of Sugars • Energy • Diet and Exercise • Production of honey, sugar, maple syrup and molasses

  8. Uses of Carbohydrates in Foods • Sweetener • Structure • Bulk (sugar substitutes) • Water Binding • “Mouth feel” • Color • Nutrition • - Calories • - Soluble and Insoluble fiber • - Intestinal transit time, cholesterol bile binding • Special uses of gums, starches and pectins: gelation, viscosity, emulsification

  9. Structure of Carbohydrates Cartoon Chemistry

  10. High Fructose Corn Syrup, What is it? How is it made? Is it natural? Is it good for you? Fructose Glucose Glucose Glucose Glucose Glucose Starch Sucrose Fructose Glucose Glucose Glucose Glucose Glucose Fructose Glucose Glucose Fructose Glucose Glucose Corn Syrup High Fructose Corn Syrup

  11. Attributes of High Fructose Corn Syrup • Its liquid form and dust-free nature make it easy to handle. • The glucose and fructose in HFCS contribute to the desirable brown colors in baked. • HFCS has greater water binding capacity than sucrose. • HFCS has sweetening, thickening, and water binding properties and can balances tartness. • HFCS is more stable than sucrose in acid products. • HFCS is more stable than some artificial sweeteners. • Its sweetness can be manipulated by varying the fructose: glucose ratio. • HFCS is not as likely as sucrose to form crystals, which can impart a “gritty” defect.

  12. Is HFCS healthy? HFCS has the same 4 Cal/g as sucrose. HFCS is not the culprit for obesity. The over consumption of calories in sweetened beverages plays a large role in the obesity problem. Sedentary life style and lack of exercise also play a large role. Excess calories can come from sucrose, corn syrup, high fructose corn syrup or fat. Over consumption of calories is not healthy.

  13. Guess the calories

  14. Guess the calories 1,443 Calories 1,500 Calories

  15. Law suits against Snapple and Arizona“Not natural”

  16. What is the legal definition of a natural ingredient?

  17. “Sugar is Back on Food Labels, This time as a Selling Point” The New York Times March 21, 2009 By Kim Severson - The quiet rivalry between sugar and high-fructose corn syrup appears to have a winner. - “ The first lady, Michelle Obama, has said she will not give her children products made with it (high-fructose corn syrup).”

  18. It’s a choice, market segmentation

  19. HFCS consumption is at a 20 year low (37 lbs per person, 44 lbs for sucrose). • “Sugar is sugar, HFCS has been highly disparaged and highly misunderstood.” • Analogy to the renaming of other foods – “Rapeseed oil”. • Even CSPI (and AMA) says sugar and HFCS are the same and have same health effect. • “Corn sugar” more easily understood and eliminates the negative connotation.

  20. Relative sweetness of sweeteners *bind water, laxative effect, gassy (caloric) 0.2 Cal/g

  21. Stevia from plant extract 300 times sweeter than sucrose Truvia based on Stevia Neotame based on Nutrasweet 7,000 – 13,000 sweeter

  22. Sugar and Sweeteners: a Molecular View

  23. A short review

  24. Trans fats “look” more like saturated fats. Trans fats “look” more like saturated fats. Polyunsaturated > monosaturated “Partially hydrogenated” fats. “Attempt” to hydrogenate 4 cis double bonds succeeds with 2, leaves one alone, creates one trans double bond.

  25. Hydrogen bonding and solubility in water “Hydrogen bonding” is nothing more than the attraction of positive and negative.

  26. Structure of sucrose

  27. Fat Structure Fatty acids are either saturated, monounsaturated (contain one C=C double bond) or polyunsaturated (contain two or more C=C double bonds) Saturated fatty acids stack closely and are more solid. Unsaturated fatty acids are more fluid. “Hydrogenating” unsaturated fatty acids makes them more rigid.

  28. Carbohydrates • Structure • Importance of glucose • Relative sweetness • Lo/no cal sweeteners • High fructose corn syrup • No definition of “natural” • My nuanced opinion of “Is HFCS good or bad?” It all depends… • “Bias”

  29. A Tale of Four Sodas

  30. Discuss web rants-Dr Oz - more-Best and worst sugars- new

  31. Other items: • How can you know? • Questions about the extra credit? • Questions about lipids, or carbs thus far? • Comments on the “Knowledge Assessment Opportunity” • Attendance

  32. Function of Starches

  33. Amylose and Amylopectin – Two forms of starch

  34. Structure of Starch Amylose = 30% of the starch, tightly packed, less digestible, insoluble in water. Amylopectin = 70% starch, soluble in water, many endings, crystalline

  35. Starch retrodegration

  36. Gluten, good or bad?Selling point? Survey: Do you think gluten is “bad”? Are you more likely to buy a product advertized as “gluten free”?

  37. Gluten • Protein from wheat, barley, and rye (rice and corn different) • Associated with starch • Gliadin + gluteline • Important global protein source • Plasticity, shape, chewiness • Celiac disease < 1.0 % of population

  38. Gums Gums - hydrocolloidal suspensions that don’t gel, aren’t soluble, but bind lots of water. Most important are non digestible soluble fiber.

  39. Soluble and Insoluble Fibers

  40. Sources of Fiber

  41. Carbohydrate Characteristics

  42. Glucose Metabolism

  43. Glycemic index of foods Glycemic index – the impact on blood glucose levels

  44. The glycemic index, glycaemic index, or GIis a measure of the effects of carbohydrates on blood sugar levels. Carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high GI; carbohydrates that break down more slowly, releasing glucose more gradually into the bloodstream, have a low GI. A lower glycemic response usually equates to a lower insulin demand but not always, and may improve long-term blood glucose control[2] and blood lipids. The glycemic index of a food is defined as the area under the two hour blood glucose response curve (AUC) following the ingestion of a fixed portion of carbohydrate (usually 50 g). The AUC of the test food is divided by the AUC of the standard (either glucose or white bread, giving two different definitions) and multiplied by 100. The current validated methods use glucose as the reference food, giving it a glycemic index value of 100 by definition. GI values can be interpreted intuitively as percentages on an absolute scale and are commonly interpreted as follows :

  45. Insulin Response to Glucose Metabolism

  46. The Effect of Diet on Physical Endurance