11-Fats+_+Oils+s11 - FST 10 Roles of fats — lecture...

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Unformatted text preview: FST 10 Roles of fats — lecture topics Animal & Plant Fats & Oils ! ! ! ! ! ! ! ! Energy source Texture Adipose Essential fatty acids Fat soluble vitamins: A, D, E, K Flavor and flavorings Heat transfer Fatty acid isomers (trans fats) We!ll now look at each of these individually FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 FATS & OILS ! Caloric Values Roles of Fats ! ! Physicists! definition: ! Energy source ! 1 calorie raises 1 gram of water 1°C 1 kcal raises 1000 grams of water 1°C ! (actually, modern physicists use Joules instead of calories, but most nutritionists still use nomenclature related to calories). FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Caloric Values Carbohydrates! ! Proteins! ! ! Fats! ! ! ! Caloric Values 4 kcals/gram 4 kcals/gram 9 kcals/gram ! Physicists! definition: ! ! ! 1 calorie raises 1 gram of water 1°C 1 kcal raises 1000 grams of water 1°C Nutritionists use the term Calorie to imply kcal or Big Calorie Multiply Calories by 4.1868 to get kJoules. FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Recommendations for Fat Intake ! Is there Controversy? Recommendations of the USDA“Dietary Guidelines for Americans” ref: fats (Jan 2005) ! ! Choose a diet low in fat, saturated fat, cholesterol, and keep trans fats low Eat less than 35% of total calories from fats and oils (keep it between 20-35% of total calories) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Is there Controversy? Revisions are (always) in the works Is there Controversy? FST10 ©GMS/GFR 2010 Types of Biopolymers in Foods Last year, Lt. Gov. Stephen L. Henry championed a bill that put minimum nutritional standards on foods sold in school vending machines Fighting ‘Big Fat’ An army is mobilizing in a war against junk food. The combatants: doctors, lawyers, preachers and moms Peg Tyne NEWSWEEK Saturday, July 27, 2002 IN BRIEF/RESTAURANTS Man Sues Fast-Food Chains for His Obesity FST10 ©GMS/GFR 2010 Is there a 'fat tax' in your future? Could be, experts say; obesity to blame, Polymer Subunit Examples Carbohydrates monosaccharides sucrose, starch Trigycerides fatty acids cooking oils Proteins amino acids collagen, gelatin but food industry scoffs Tuesday, April 30, 2002 By LANCE GAY SCRIPPS HOWARD NEWS SERVICE WASHINGTON -- It's official: We're fat. Metabolic Syndrome By Associated Press A man sued four leading fast-food chains, claiming he became obese and suffered from other serious health problems from eating their fatty cuisine. Fatty Acids & Soaps Trigycerides - (Fats & Oils) ! 3 fatty acids attached to glycerol (McGee) ! To take off the fatty acids, one method is ! Saponification: treatment of fats with a strong base (lye) to give salts of fatty acids (soap) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 FATS & OILS Triglyceride hydrolysis ! ! ! For digestion, we also need to hydrolyze the fatty acids off the glycerol ! There!s that word hydrolysis again… But we can!t use lye, so we use enzymes called lipases Q: Why do we care? A: Only free fatty acids are absorbed What’s the difference? ! ! Fats are (semi)-solids at room temperature Oils are liquid at room temperature Normal hydrolysis of triglycerides breaking off the fatty acids (blue) by lipase (orange) FST10 ©GMS/GFR 2010 Percentages of Fat — The Games People Play ! ! For example; “95% Fat Free” means 5% fat Nutritionists recommend <30% (+/-) by Calories ! ! Lift pencils for a moment . . . Food industry labels fat% by weight and they like to tell you how fat isn!t there ! FST10 ©GMS/GFR 2010 And they think "calories! for diets These 2 numbers can be very different FST10 ©GMS/GFR 2010 Fat Content - Example 1 Fat Content - Example 1 Calculate % calories from fat We’ll use this to examine fat content ! 100 grams of food (no water — dry food) ! 70 grams of CHO!s and protein Could be labeled 70% "fat free! (30% fat) Since the labeling refers to % by weight 100 grams of food (no water, just dry food) ! 30 g of from fat ! 70 g of CHOs and protein ! So, remember it!s 30% fat by weight ! Calculate calories: ! 30 x 9# # ! 70 x 4# # !T otal kcal# 30 grams of fat ! ! ! ! ! = 270 kcal (fat) = 280 kcal (CHO!s & protein) = 550 kcal % fat by calories = 270/550 x 100 = 49% (almost half) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Fat Content - Example 2 ! What would happen if we added 5 times the amount of water? ! ! 70 grams of CHO!s and protein ! ! 30 grams of fat ! Fat Content - Example 2 500 grams of water for a total of 600 g of food Calculate the calories: Fat# # # CHO/Protein# Water# # Total# # ! The % fat by weight is now 30/600 x 100 = 5% ! ! Could be labeled "95% fat free! (5% fat) ! 30 x 9# # 70 x 4# # 500 x 0# # # # The % fat by weight now = 30/600*100 = 5% % fat by calories = 270/550 x 100 = 49% Bottom line: ! It!s now “95% fat free” ! But the % calories from fat is the same (almost half) FST10 ©GMS/GFR 2010 More bottom line ... ! ! By diluting a food with water, the % fat # (by weight) will go down However, just diluting with water does not change the % of calories from fat = 270 kcal = 280 kcal = 000 kcal = 550 kcal FST10 ©GMS/GFR 2010 An example of ‘low fat’ franks ! ! 3% fat (by weight) 20% of calories from fat (all other things being equal) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Another example ... With high water content ... FST10 ©GMS/GFR 2010 For Low-Fat types For Low-Fat types ! Simplesse™ (made by NutriSweet & CP-Kelco) ! However, “up to 1% fat is OK made from dairy & egg proteins ! can be formulated as a powder ! may have problems with heating ! 1 calorie vs. 9 calories FST10 ©GMS/GFR 2010 For Low-Fat types ! The Olean and Healthy Snacking segment airing on Chemically bonds fatty acids onto sugar molecules ! Get the facts about Olean brand olestra, the no-fat cooking oil with the full-fat flavor! Here you'll find the specific information you're looking for about olestra and your favorite snacks. Just click on the topic you would like to know about or type a word or phrase in the search box. Olestra (Olean™ — Proctor & Gamble) ! Olestra — Controversial So large, they are indigestible TV Series! Click Here For The Newest Information For Health Care Professionals! Click on the Olean Benefit most important to you. Find the information about olestra that you are looking for: Click here for: Type a few words, then click Want Great Taste ? Find Out More Here. Sensible Snacks! Low- fat foods form a foundation for healthy eating. Olean is a smart tool in the fight against fat! Where can I find snacks made with Olean? Right here! Click for a list of greattasting, name - brand chips made with Olean! And for answers to common questions about Olean and Olestra, click here! Normal hydrolysis of triglycerides breaking off the fatty acids (blue) by lipase (orange) © 2000 Procter & Gamble Legal Terms and Conditions Privacy Statement FST10 ©GMS/GFR 2010 Special Information for: Olestra — Controversial For Immediate Release: October 25, 2004 Related Links: Letter to FDA The FACTS About Olestra (Olean) Olestra Report Form Keep Updated: Email updates RSS syndication Print Version Olestra — Controversial FDA Home Page | Search FDA Site | FDA A -Z Index | Contact FDA CSPI Warns Consumers About Frito- Lay “Light” Chips with Olestra “WOW!” Chips Have New Name, But Same Old Side Effects, Says CSPI The Center for Science in the Public Interest (CSPI) today warned consumers that Frito- Lay’s “Light” snack chips are fried in the infamous, diarrhea- inducing fake fat known as olestra . Formerly known as WOW! chips, the rebranded products are now called Lays’s Light, Ruffles Light, Doritos Light, and Tostitos Light. CSPI says the move increases the odds that unwitting consumers will experience the cramps, diarrhea, bleeding, stained underwear, or incontinence associated with olestra. Today CSPI sent nearly 300 individual reports of olestra - related adverse reactions to the Food and Drug Administration (FDA). The FDA had already received more than 20,000 such reports—more than for any other food additive in history. Most of the reports involve diarrhea, gas, and cramps. Several of the recent victims sought emergency - room treatment, including a 33 - year - old Georgia woman who experienced severe cramping and diarrhea after eating olestra - containing Ruffles chips. Several victims reported embarrassing episodes of fecal incontinence in the workplace; one 19 - year - old man became incontinent on a date. “If you’re going to buy Lay’s Light, Ruffles Light, or Doritos Light, you also might want to stock up on Cottonelle, Quilted Northern, or Charmin—and plan not to stray too far from the bathroom,” CSPI executive director Michael F. Jacobson said. “Frito - Lay should have rebranded these chips as ‘OW!’ chips. This sudden name change is just a desperate attempt to revive a dying brand. Frito- Lay should have just pulled the plug altogether.” One 25 - year - old woman from South Bend, Ind., recently ate some Ruffles Light Cheddar & Sour Cream potato chips and reported severe diarrhea, gas, and nausea. “I did not notice until after reading the ingredients and having severe intestinal problems [that] olestra was in the ingredients,” she wrote on CSPI’s web- based complaint form. “My reaction was severely unpleasant.” In August 2003 the FDA dropped its requirement for a warning label on packages of olestra - containing chips. The label had read, “This product contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E and K have been added.” In May of this year, the FDA approved olestra for use in microwave popcorn, though no popcorn makers have begun using it. “I threw away all my WOW! products,” wrote one 42 - year - old woman from Dearborn, MI. “The pain was extreme.” FDA Talk Paper T03 - 59 August 1, 2003 Health Canada Rejects Olestra as a Food Additive Media Inquiries: 301 - 436 - 2335 Consumer Inquiries: 888 - INFO - FDA FDA Changes Labeling Requirement for Olestra The Food and Drug Administration (FDA) today announced a change in the labeling requirement for olestra - - the zero calorie fat substitute developed by Procter & Gamble Co. (P&G) for use in certain snack foods - - because FDA has concluded the label statement is no longer warranted. As a result of this decision, manufacturers will not be required to display the 1996 label statement on products containing olestra. However, FDA will require manufacturers to continue adding Vitamins A, D, E, and K to such products. Consumers will now see an asterisk after each of these added fat - soluble vitamins listed in the ingredient statement of products containing olestra. The asterisk will reference the statement, "Dietarily insignificant." FDA approved olestra in 1996 for use in savory snacks like potato chips, cheese puffs, and crackers. As part of that approval, FDA required manufacturers to add vitamins A, D, E, and K to olestra - containing foods to compensate for olestra’s effects on these fat - soluble vitamins. Also, as part of that approval, FDA required manufacturers to place a label statement on all products made with olestra informing consumers that olestra may cause abdominal cramping and loose stools in some individuals, that it inhibits the body’s absorption of vitamins A, D, E, and K and other nutrients, and that these vitamins have been added to compensate for olestra’s effects on these nutrients. FDA conducted a scientific review of several post - market studies submitted by P&G, as well as adverse event reports submitted by P&G and the Center for Science in the Public Interest. FDA concluded that the label statement was no longer warranted because: "Real - life" consumption studies of products containing olestra showed olestra caused only infrequent, mild gastrointestinal (GI) effects. In fact, a 6 - week study with more than 3,000 people showed that the group consuming olestra - containing chips experienced only a minor increase in bowel movement frequency compared to those people who consumed only full- fat chips. Post - market studies showed consumers are aware of olestra and its potential GI effects. Post - market consumer studies showed that consumers were confused by the required label because they did not understand that the label meant there would be no loss of vitamins. These post - market studies also indicated that consumers erroneously believed that vitamins and minerals not affected by olestra would be lost. At a 1998 FDA Foods Advisory Committee meeting there was agreement that an asterisk- linked statement on the ingredient panel about added vitamins A, D, E, and K would be more useful to consumers. While the current labeling requirements are effective immediately, FDA realizes and consumers can expect that there may be a period of time before companies introduce the new product label. For additional information, please visit http://www.fda.gov/OHRMS/DOCKETS/98 fr/00 F- 0792NFR00001.pdf . For Immediate Release: June 22, 2000 For more information: Bill Jeffery (613)565 - 2140 OTTWA, CANADA - Health Canada has rejected olestra, the indigestible fat substitute made by Procter and Gamble, for use as a food additive in Canada. According to a letter sent June 8 by Marc Le Maguer, the Director General of the Food Directorate, "Health Canada has completed its review of Olestra and has decided not to recommend that Olestra be permitted for use as a food additive in Canada." "We're pleased that Health Canada has decided to protect Canadians from olestra -containing products," said Michael Jacobson, executive director of the Centre for Science in the Public Interest (CSPI), a long -time opponent of olestra. "That will spare Canadians the gastrointestinal grief that thousands of U.S. consumers have experienced." While Health Canada is saying "no" to olestra, the U.S. Food and Drug Administration (FDA), under pressure from Procter and Gamble, is considering dropping the olestra warning notice ("may cause abdominal cramping or loose stools") from packages. The FDA has received more than 18,000 adverse -reaction reports related to olestra (2,687 from CSPI; more than 16,000 from Procter and Gamble). That's more such reports than the FDA has received for all other food additives in history combined. Many reports describe cases of severe diarrhea, including several Canadians who ate olestra -containing products on visits to the U.S. CSPI urges people who believe they suffered adverse effects as a result of eating olestra to file a report . Jump to: ### Role of Fats ! ! Energy source Texture FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Polymorphism ! More than one form of a substance ! ! Example: !, " & "! crystals (FST 100a) From Greek “many forms” ! Why learn the (Greek) derivations? 1.35 FST10 ©GMS/GFR 2010 Roles of Fats ! ! ! Energy source Texture Adipose tissue ! ! Prime Choice Select e.g. Marbling of meat USDA grading is based on fat distribution Standard Utility Cutter FST10 ©GMS/GFR 2010 Roles of Fats ! Essential fatty acids ! Texture ! Adipose Are essential to proper metabolism ! Energy source Cannot be synthesized by the body ! ! ! (or at least in sufficient amounts) ! ! Linolenic ($3) ! Essential fatty acids Linoleic ($6) & maybe arachidonic ($6) acids ! Biochemists are still not certain exactly which ones are essential and how much you need ! For further reading, see McGee FST10 ©GMS/GFR 2010 Essential fatty acids ! Prostalglandins Thought related to the production of these powerful hormones and biochemicals: ! Prostalglandins ! Leucotrienes Thromboxanes ! ! FST10 ©GMS/GFR 2010 Probably the best known are the prostalglandins (seen in next slide) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Roles of fats ! Roles of fats ! Energy source Texture Adipose Essential fatty acids Fat soluble vitamins: A, D, E, K ! Flavor and flavorings ! Energy source ! Texture ! Adipose ! ! ! ! Essential fatty acids ! Fat soluble vitamins: A, D, E, K ! ! This topic is for nutrition classes… 3 effects follow on the next 3 slides… FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Roles of fats — Flavor ! Roles of fats — Flavor ! 1-Storage of flavor compounds ! 1-Storage of flavor compounds 2-Specific for a product ( e.g. butter ) FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Roles of fats Roles of fats — Flavor ! ! ! 1-Storage of flavor compounds 2-Specific for a product ( e.g. butter ) 3-Without fat - flavor is a problem (“Ain!t Nothin! good without the grease” - Tina Turner FST10 ©GMS/GFR 2010 ! ! Energy source Texture ! Adipose Essential fatty acids ! Fat soluble vitamins: A, D, E, K ! Flavor and flavorings ! ! Heat transfer FST10 ©GMS/GFR 2010 Fats, Double Bonds & Saturation (everything you were afraid to ask) Roles of fats: heat transfer ! ! ! Large molecules do not evaporate Can be heated to very high temperatures Heat transfer with hot fat is called: frying ! FST10 ©GMS/GFR 2010 HH FST10 ©GMS/GFR 2010 HH HCCH The world!s shortest (and oversimplified) explanation of double bonds, saturation and unsaturation follows ... HCCH HH Ethane Single Bond Ethylene Double Bond See also McGee FST10 ©GMS/GFR 2010 C-18 Fatty Acids What’s with the OMEGA numbers? COOH 18:0 — Stearic Acid ! Nutritionists are interested in the end of the molecule farthest from the acid group COOH 18:1 — Oleic Acid ! So the “last carbon” is like the last letter of the Greek alphabet — $ COOH COOH 18:2 — Linoleic Acid ! They number in from the (omega) end until they come to the 1st double bond C-18 Fatty Acids COOH 18:0 — Stearic Acid COOH 18:1 — Oleic Acid COOH 18:2 — Linoleic Acid COOH 18:3 — Linolenic Acid $9 $6 $3 18:3 — Linolenic Acid FST10 ©GMS/GFR 2010 OMEGA numbers & saturation ! Nutritionists are interested in the proportions of the fatty acid types ! Monounsaturated ! ! Polyunsaturated ! OMEGA numbers & saturation Saturated Nutritionists are interested in the proportions of the fatty acid types ! ! ! Polyunsaturated Monounsaturated Saturated FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Fatty acid stuff — Too advanced for FST10 (Don’t write these down; these are just in case you read something about them like the label below...) OMEGA numbers & saturation ! ! Some biochemists & nutritionists use lower case “n” instead of $; well sort of... ! Things like ALA are different from GLA ! There are weird things that happen with some acids like “conjugated linoleic acid” ! FST10 ©GMS/GFR 2010 Chemists locate double bonds from the acid end & use the Greek symbol delta (%) See FST100 and advanced nutrition courses FST10 ©GMS/GFR 2010 But we do need to know a little more about Fatty Acid Cis & Trans Isomers Double Bonds H H CC ! ! 2HC Even though the number of atoms is the same there can be isomers Commonly referred to as CIS & TRANS double bonds CH2 CIS 2HC H H CC CH2 TRANS FST10 ©GMS/GFR 2010 Even more about... Double Bonds trans- fat. What’s that? Some fatty acids have carbon-carbon double bonds they are not “saturated” with hydrogen. cis- and trans unsaturations have •different shapes •different chemistries, and are broken down by •different enzymes O saturated CH3 CH2 CH2 CH2 CH2 ... CH2 C OH trans -unsaturated Naturally-occurring fatty acids are cis- ! Cis double bonds are found in FAs in nature Trans double bonds are formed as byproducts of a synthetic chemistry processes called: ! “Hydrogenation” and are “Un-natural” or “Synthetic” H CH3 CH2 C O C cis -unsaturated Fatty acids may have more than one unsaturation (mono-,di-, ... poly) ! CH3 CH2 ... CH2 C OH H CH2 H C O C CH2 ... CH2 C OH H FST10 ©GMS/GFR 2010 Catalytic Hydrogenation ! Lipids containing highly unsaturated FAs are liquids at room temperature - Oils. ! Lipids containing saturated FAs are solids at room temperature - Fats. ! Convert Vegetable oil to Margarine by catalytic hydrogenation - saturating SOME of the double bonds - partial hydrogenation. ! Partial hydrogenation also converts cisunsaturations to trans-double bonds - “transfat”. FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Even more about double bonds ! ! ! European-led research is beginning to tell us something… Cis double bonds are formed in nature Trans double bonds are formed by synthetic chemistry —> hydrogenation and are “un-natural” On labels look for “partially hydrogenated” oils of some kind FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 Changing perception — avoid cholesterol or trans fats? Previous exam examples FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 5) Which meat grade below has the greatest amount of marbling? 3) Which term describes the distribution of fat throughout meat tissue? ! ! ! ! ! a) Myoglobin b) Polymorphism c) Cellulite d) Marbling e) Retrogradation ! ! ! ! ! FST10 ©GMS/GFR 2010 a) Select b) Utility c) Standard d) Cutter e) Choice FST10 ©GMS/GFR 2010 6) This many calories are found in one gram of fat: ! ! ! ! ! a) 1 b) 3 c) 4 d) 4.6 e) 9 7) Diluting a food with water will ____ the % calories from fat. ! ! ! ! ! a) Increase b) Decrease c) Not change d) Exponentially increase e) Significantly decrease FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 9) Which vitamin is not fatsoluble? 8) What causes the formation of “chunky butter?” ! ! ! ! ! a) Retrogradation b) Improper churning c) Making butter from non-fat milk d) Different forms of fat crystals e) Low humidity storage ! ! ! ! ! a) A b) C c) D d) E e) K FST10 ©GMS/GFR 2010 FST10 ©GMS/GFR 2010 10) Saturated fatty acids have _____ double bonds. ! ! ! ! ! a) 0 b) 1 c) 2 d) 3 e) $-3 11) Trans double bonds are synthetically formed through a process called ! ! ! ! ! FST10 ©GMS/GFR 2010 a) Saponification b) Hydrogenation c) Hydrolysis d) Retrogradation e) Marbling FST10 ©GMS/GFR 2010 Animal & Plant Fats & Oils Fini … FST10 ©GMS/GFR 2010 ...
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This note was uploaded on 01/26/2012 for the course FST 10 taught by Professor Jack during the Spring '08 term at UC Davis.

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