Animal&PlantFood Lipids"Fats & Oils".IntroductionLipids.Majorlipid componentsMinorcomponentsWorking definition.DietaryfatsOrganic compounds (CHO) that do·Processingnot mix with Water·ChemicalpropertiesLipid oxidationandantioxidants.HealtheffectsWe will use the term lipids"mostlyEffectofLipidCompositionandProcessingon FunctionalityofFoodsFood CaloricValuesMAJORCOMPONENTSEFFECTS/FUNCTIONSSPECIFICScolor,FlavorTextureQUALITYATTRIBUTESNutritionists use the term Calorie (big C) to imply kcalSensory propertiesAffectAPPLICATIONS1Kilocalorie (kcal)=1Calorie=1000caloriesShortenings, MargarineCOMPOSITIONANDSpreads, EmulsionsPROCESSINGFUNCTIONALITYStructured lipidsConfectionryproductsAffect.In Europe -joules (welcometothemetric system!)Chemical and physicalpropertiesESSENTIALNUTRIENTSLinoleic acid,.4.2 joules=1 calorieLinolenic acid,NUTRITIVEVALUELong -chain PUFAorVitamins: A, D, E, K4.2 Kilojoules (ki) = 1 kcal = 1 CalAntioxidants
1 Animal & Plant Fats & Oils Lipids Working definition: Organic compounds (CHO) that do not mix with Water We will use the term lipids mostly Food Lipids • Introduction • Major lipid components • Minor components • Dietary fats • Processing • Chemical properties • Lipid oxidation and antioxidants • Health effects Effect of Lipid Composition and Processing on Functionality of Foods MAJOR COMPONENTS EFFECTS/FUNCTIONS SPECIFICS Color, Flavor Texture QUALITY ATTRIBUTES FUNCTIONALITY APPLICATIONS Shortenings, Margarine Spreads, Emulsions Structured lipids Confectionary products NUTRITIVE VALUE ESSENTIAL NUTRIENTS Linoleic acid, Linolenic acid, Long –chain PUFA Vitamins: A, D, E, K Antioxidants COMPOSITION AND PROCESSING Affect Affect Chemical and physical properties Sensory properties Food Caloric Values • Nutritionists use the term Calorie (big C) to imply kcal • 1 Kilocalorie (kcal) = 1 Calorie = 1000 calories • In Europe - joules ( welcome to the metric system!) • 4.2 joules = 1 calorie or 4.2 Kilojoules (kj) = 1 kcal = 1 Cal
Caloric ValuesRecommendationsforFat(fatsandoils)IntakeCarbohydrates4kcals/gram.Recommendations oftheProteins4kcals/gramUSDA"Dietary Guidelines forLipids9kcals/gramAmericans"ref: fatsChoose a diet low in fat,SowecansaythatLipidshavetwicethesaturatedfat, and cholesterolamountofKcaloriesasCarbohydrates*or-Eat lessthan30%of totaProteinscalories from fats and oils*digestiblecarbohydrates2010USDietaryGuidelinesAnexampleof‘lowfat'hotdogs·3%fat (byweight)Besti.20%ofcaloriesKOS97%FAT FREEfrom fatBeef Frankfurters10D
2 Carbohydrates 4 kcals/gram Proteins 4 kcals/gram Lipids 9 kcals/gram So we can say that Lipids have twice the amount of Kcalories as Carbohydrates* or Proteins. *digestible carbohydrates Caloric Values Recommendations for Fat (fats and oils) Intake • Recommendations of the USDADietary Guidelines for Americans ref: fats –Choose a diet low in fat, saturated fat, and cholesterol –Eat less than 30% of total calories from fats and oils 2010 US Dietary Guidelines Limit your intake of Empty Calories. Empty Calories are from food components such as added sugars and solid fats that provide little nutritional value. Empty Calories are part of Total Calories. An example of low fat hotdogs • 3% fat (by weight) • 20% of calories from fat
LipidContentofSomeFoodsWith highwater contentFoodsg lipid per100gfood0.0beer3.2breadHeart3.4chickencambba3.5milk8.3pizzaHealthyRequest.11.5eggsHeartyChicken Vegetable20.3hamburger30.0cheese(processed)39.8potatochipssteak42.279.9mayonnaise81.0margarine/butterUSDA Agricultural Handbook No, 8HistoryConsumptionofFatsApproximately80to140gramsperday:An vegetable oil is a triglyceride extractedmadeupofvisibleandinvisiblefatsfrom a plant.Such oils have been part ofhumancultureformillenniaVisiblefats(60+grams):fryingfats,shortenings,vegetablesalad oilsbutter,lard?Although many plantparts mayyield oil incommercialpractice,edibleoil is extractedInvisiblefats(80 grams):lipid components ofprimarilyfrom seedsfoods:meat,chicken,turkey,fish,bread,milkanddairyproducts,potatochips,donuts
3 With high water content . Foods g lipid per 100 g food beer 0.0 bread 3.2 chicken 3.4 milk 3.5 pizza 8.3 eggs 11.5 hamburger 20.3 cheese (processed) 30.0 potato chips 39.8 steak 42.2 mayonnaise 79.9 margarine/butter 81.0 USDA Agricultural Handbook No. 8 Lipid Content of Some Foods Consumption of Fats • Approximately 80 to 140 grams per day made up of visible and invisible fats • Visible fats (60+ grams): frying fats, shortenings, vegetable salad oils, butter, lard • Invisible fats (80 grams): lipid components of foods: meat, chicken, turkey, fish, bread, milk and dairy products, potato chips, donuts History • An vegetable oil is a triglyceride extracted from a plant. Such oils have been part of human culture for millennia. • Although many plant parts may yield oil in commercial practice, edible oil is extracted primarily from seeds
World productionOil Production.Palm oil is the largest in.Mechanical extraction"crushing"or"pressing”quantity of all vegetable oils.Oldermethod used toproducethemoretraditional oils (e.g.,oliveand palm).Soybean oil isthe largest inquantity.SolventextractionThemostcommon solventispetroleum-derivedhexane" This technique is used formost of the"newer"MILDTECHNOLOGYNATURALLY...VirginThe word"virgin" used by the legislation todescribeolive oilmeanspreciselythisBecause a fruit is rich in water, its oil can be extractedby purely mechanical means."That the oil has been extracted from the olivesusingpurelymechanicalmeans."Aftercrushing of thefruit,waterandoil canalsobeeasily separated by centrifugation
4 World production • Palm oil is the largest in quantity of all vegetable oils. • Soybean oil is the largest in quantity of all edible vegetable oils. 13 Oil Production • Mechanical extraction "crushing" or "pressing” Older method used to produce the more traditional oils (e.g., olive and palm) • Solvent extraction The most common solvent is petroleum-derived hexane. This technique is used for most of the "newer" industrial oils such as soybean and corn oils. 14 MILD TECHNOLOGY, NATURALLY. Because a fruit is rich in water, its oil can be extracted by purely mechanical means. After crushing of the fruit, water and oil can also be easily separated by centrifugation. Virgin The word virgin used by the legislation to describe olive oil means precisely this: That the oil has been extracted from the olives using purely mechanical means.
Animal FatsOilRefining:Animal fats and oils are lipid materialsderived from animals.:Today most food oils are"refined"that is separated from?Physically,oils are liquid at roomorganic solvents (Chemical Means)temperature,and fats aresolid.:Chemically,bothfats and oils are composed. The solvents are then boiled away leaving the oil andof triglyceridesother plant compounds behind..The separationof fat from animal tissue is.The solvents can be reused.18called renderingFunctions of FatsHealthaspects:CLASSESOFFATS&OILSConcentratedsourcesofcalories (9Kcal/g)Provide30to40%ofcaloriesofU.S.dietDILNCHANTATIYACIOELONG-OWNFATTYACOSThereisgreatinterest inmodificationoflipidOccontentandcomposition.However,fatsdomoreSTthanprovidecaloriesPhysical and chemical functions:Impactontasteandtexture.Thesepropertiesoemustbesimulatedinlow-fatfoodsSatiety:“full"or"stuffed"feelingWITAYCROCDTCN
5 17 Oil Refining • Today most food oils are refined” that is separated from the plant seeds with organic solvents (Chemical Means). • The solvents are then boiled away leaving the oil and other plant compounds behind. • The solvents can be reused. Animal Fats • Animal fats and oils are lipid materials derived from animals. • Physically, oils are liquid at room temperature, and fats are solid. • Chemically, both fats and oils are composed of triglycerides. • The separation of fat from animal tissue is 18 called rendering. Functions of Fats • Health aspects: Concentrated sources of calories (9 Kcal/g). Provide 30 to 40 % of calories of U.S. diet. There is great interest in modification of lipid content and composition. However, fats do more than provide calories. • Physical and chemical functions: Impact on taste and texture. These properties must be simulated in low-fat foods. • Satiety: full or stuffed feeling.
Functionsof FatsFlavor:sourceofdesirableandundesirableflavorsdesirableflavors:fromlactonesanddiacetylinbutter,ketonesincheeseundesirableflavors:rancid,tallowy and fishyflavors.2,4-decadienal:atlowlevelsprovidesdesirablefriedfoodflavortopotatochips,butatKagomehighlevelsimpartsundesirablerancidflavorsColor:sheenimpactfromwaxes,yellowcolorfromcarotenoids,greenfromchlorophyilsTexture:mouth feel in butter and margarine,smoothfeelofmilkandicecreamRoles of Fats.EnergysourceChoiceSele.Texture-Adipose tissue?E.g.Marbling of meat.USDAgradingisbased on fatdistribution
6 Functions of Fats • Flavor: source of desirable and undesirable flavors desirable flavors: from lactones and diacetyl in butter, ketones in cheese. undesirable flavors: rancid, tallowy and fishy flavors. 2,4-decadienal: at low levels provides desirable fried food flavor to potato chips, but at high levels imparts undesirable rancid flavors. • Color:: sheen impact from waxes, yellow color from carotenoids, green from chlorophylls • Texture: mouth feel in butter and margarine, smooth feel of milk and ice cream Roles of Fats • Energy source • Texture – Adipose tissue • E.g. Marbling of meat • USDA grading is based on fat distribution Prime Choice Select Standard Utility Cutter
Lipids·MajorlipidcomponentsThe building blocks·Fatty acidsTriacylglycerols (triglycerides)glycerolayacdPhosphoglycerides(phospholipids).Minorcomponents.Hydrocarbons,Sterols,Tocopherols,CarotenoidsDietaryfats福Essentialfattyacids,Eicosanoids,Biological functionsTriglycerideorFattyAcidStructureTriacylglycerols?R-groupsonfattyacidchainsaregenerallylinear hydrocarbons, e.gtriglyceridePCHCHCHCHCHCHCHCH-0-CCH,CH,CH,CH,CH,CH,CH,which may be more simply represented asO0-
7 Lipids • Major lipid components • Fatty acids • Triacylglycerols (triglycerides) • Phosphoglycerides (phospholipids) • Minor components • Hydrocarbons, Sterols, Tocopherols, Carotenoids • Dietary fats • Essential fatty acids, Eicosanoids, Biological functions The building blocks OH OH OH Triglyceride or Triacylglycerols Fatty Acid Structure • R-groups on fatty acid chains are generally linear hydrocarbons, e.g. which may be more simply represented as C O - O - CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2 C O - O -
NumberingSchemesFattyAcidChainRepresentation.Scientists in the medical and nutrition communityoftennumbercarbonsfromtheopposite(tail)endThesymbolAfollowedbythecarbonnumberisthis nomenclature uses o to denote the double bond positionusedto indicatetheposition ofthedoublebondE.g.themoleculeE.g.18:1A9O14Q713151010716114nated as 18:3 9,12.15,or as 18:3 o3.6,9canpeeconsists of 18carbonswith1doublebond located-1between the gth and 10th carbon.161218ImportantFoodFattyAcidConstituentsSystematicNamesAbbreviatiotSymbol4:0ButanoicButyricB60HHexanoicCapole.Prefixindicatesnumberofcarbons8.0oeOctanoicCaprylic10:0DDecaneicCapric.Suffix indicates degree ofunsaturation1204DodeLauric14:0MyristicMTetrad-"-anoic"if saturated16:0PalmiticHexadP-"-enoic"if monounsaturated15:0Stearie5Octade18:1Oleico9.Octad-"-adienoic"iftwodoublebonds18:29,12-0ctadecaLinoleic49,12183LinolenicL9,12.15-Dctadecatrieneic"-atrienoic" if three double bonds20:0EicosanoicArachadio420:4An5,8,11,14-EArachadoni-"-atetraenoic"if fourdouble bonds22:4Erucic
8 Fatty Acid Chain Representation • The symbol Δ followed by the carbon number is used to indicate the position of the double bond E.g. 18:1Δ9 consists of 18 carbons with 1 double bond located between the 9th and 10th carbon. 12 14 16 18 11 13 15 17 1 3 5 7 9 10 2 4 6 8 C O - O - Numbering Schemes • Scientists in the medical and nutrition community often number carbons from the opposite (tail) end – this nomenclature uses ω to denote the double bond position E.g. the molecule can be designated as 18:3 Δ9,12,15, or as 18:3 ω3,6,9. 12 18 14 16 11 13 15 17 10 C O - O - 1 2 3 4 5 6 7 8 9 18 16 14 12 17 15 13 11 10 C O - O - 1 2 4 3 5 7 6 8 9 Systematic Names • Prefix indicates number of carbons • Suffix indicates degree of unsaturation – -anoic if saturated – -enoic if monounsaturated – -adienoic if two double bonds – -atrienoic if three double bonds – -atetraenoic if four double bonds Important Food Fatty Acid Constituents Abbreviation Systematic Name Common Name Symbol 4:0 Butanoic Butyric B 6:0 Hexanoic Caproic H 8:0 Octanoic Caprylic Oc 10:0 Decanoic Capric D 12:0 Dodecanoic Lauric La 14:0 Tetradecanoic Myristic M 16:0 Hexadecanoic Palmitic P 18:0 Octadecanoic Stearic St 18:1 9-Octadecenoic Oleic O 18:2 9,12-Octadecadienoic Linoleic L 18:3 9,12,15-Octadecatrienoic Linolenic Ln 20:0 Eicosanoic Arachadic A 20:4 5,8,11,14-Eicosatetraenoic Arachadonic An 22:1 13-Docosenoic Erucic E Δ9,12
SATURATEDANDUNSATURATEDFATTYACIDS.COOHFoodFattyAcidConstituentsStearic acid: octadecanoic acid (18:0)MostfoodfattyacidsCOOHOleic acid: cis-9-octadecenoic acid (18:1 n-9)-Evennumberofcarbons- Linear (not branched)COOH-Double bonds in nature are cisLinoleic acid: cis-,cis-12-octadecadienoic acid (18:2 n-6)- Even though trans double bonds are in lower energy state.Erucic acidfound naturally inbrassicus rapus (rapeCOOHseed)Linolenic acid: cis-8,cis-12,cis-15-octadocatrienoic acid (18:3 n-3) Modem cultivar developed with low levels of erucic acidCOOH: Canola oilArachidonic acid: cis-5,cis-8,cis-11,cis-414-eicosatetraenoic acid (20:4 n-6)POLYUNSATURATEDFATTYACIDSFattyAcidStructureCOOHLinolelc acid: cls-8,cis-12-octadecadienolc acid (18:2 n-6)CarboxylO0groupCCOOHLinolenic acid; cis-,cis-12,cis-15-octadecatrienoic acld (18:3 n-3)COOHArachidonic acid: cis-5,cis-8,cis-11,cis-14-elicosatetraenolc acid (20:4 n-6)ACOOHHydrocarbonElcosapentaenolc acid:20:5 n-3 (EPA)chainCOOHDocosahexaenoic acid: 22:6 n-3 (DHA)(a)(b)
9 Food Fatty Acid Constituents • Most food fatty acids – Even number of carbons – Linear (not branched) – Double bonds in nature are cis • Even though trans double bonds are in lower energy state • Erucic acid found naturally in brassicus rapus (rape seed) – Modern cultivar developed with low levels of erucic acid • Canola oil SATURATED AND UNSATURATED FATTY ACIDS COOH Stearic acid: octadecanoic acid (18:0) COOH Linoleic acid: cis-9,cis-12-octadecadienoic acid (18:2 n-6) COOH Oleic acid: cis-9-octadecenoic acid (18:1 n-9) COOH Linolenic acid: cis-9,cis-12,cis-15-octadecatrienoic acid (18:3 n-3) COOH Arachidonic acid: cis-5,cis-8,cis-11,cis-14-eicosatetraenoic acid (20:4 n-6) POLYUNSATURATED FATTY ACIDS COOH Linoleic acid: cis-9,cis-12-octadecadienoic acid (18:2 n-6) COOH Linolenic acid: cis-9,cis-12,cis-15-octadecatrienoic acid (18:3 n-3) COOH Arachidonic acid: cis-5,cis-8,cis-11,cis-14-eicosatetraenoic acid (20:4 n-6) COOH Eicosapentaenoic acid:20:5 n-3 (EPA) COOH Docosahexaenoic acid: 22:6 n-3 (DHA)
PropertiesofFattyAcidsSaturated fatty acids havehighmeltingpoints-65°C (fat)Mono-Unsaturated fatty have low M.P,'s ~ 10°C (oil)Poly-Unsaturated fatty acids have even lower M.P.s~-10°C (oil)Trans-fatty acids have moderate melting points ~ 45C (fat)SaturatedMixtureofsaturated and(more like saturated fatty acids)fattyacidsunsaturated fattyacids(c)(d)AverageFattyAcidCompositionofFats&OilsSaturatedandUnsaturated(% by wt)Fatty acidsFats16:018:018:118:218:311422538Soybeanaturatec24562610Canola652069Sunflowertrace133521Corn311027871Olive2271851CottonseedtracePalm4444010trace27Lard114411others277482Tallowothersfo/y-nnsaturatee
10 Properties of Fatty Acids Saturated fatty acids have high melting points ~65°C (fat) Mono-Unsaturated fatty have low M.P.s ~ 10°C (oil) Poly-Unsaturated fatty acids have even lower M.P.s ~ -10°C (oil) Trans-fatty acids have moderate melting points ~ 45°C (fat) (more like saturated fatty acids) Saturated and Unsaturated Fatty acids Fats 16:0 18:0 18:1 18:2 18:3 Soybean 11 4 22 53 8 Canola 4 2 56 26 10 Sunflower 6 5 20 69 trace Corn 13 3 31 52 1 Olive 10 2 78 7 1 Cottonseed 27 2 18 51 trace Palm 44 4 40 10 trace Lard 27 11 44 11 others Tallow 27 7 48 2 others Average Fatty Acid Composition of Fats & Oils (% by wt)