Paper P6-3 Analytical Methods for Trans-Fatty Acid ...

1 136 Paper P6-3 Analytical Methods for Trans-Fatty Acid AnalysisMike kennedy , cargill AnalyticalANALYTICAL Methods FOR trans fatty ACID ANALYSISM ichael kennedy , cargill Inc., Minnetonka, MN 55328 ABSTRACT The AOAC Technical Division on Reference Materials is in the process ofdeveloping a reference material for the analysis of trans fatty acids. If successful,these materials will become available through the AOAC. Two materials havebeen prepared, a non-hydrogenated soybean oil with approximately 3% transfatty acids and a hydrogenated soybean oil with approximately 25% trans .

2 In oureffort to find the true value, these samples were sent to several experiencedlaboratories for analysis . Data will be presented showing the variability of thedata generated by the IR method and the capillary GC method. Limitations ofeach method will be discussed. Industry activity in Response to trans FattyAcids Concerns. The vegetable oil industry is responding to the concern overtrans fatty acids in the diet. They are developing new processing procedures tominimize the formation of trans fatty acids during processing.

3 Current processingpractices (specifically deodorization and hydrogenation) and their influence ontrans fatty acid formation, will be presented. New processing procedures, aimedat the reduction of trans fatty acids in vegetable oils, will be also Technical Division On ReferenceMaterialsTrans- fatty Acid Reference MaterialSample PreparationlTwo Soybean Oil Samples Were ObtainedContaining Approximately 5% and 30% TotalTranslSamples Were Melted Under NitrogenlMixedlPackaged In Glass 7 ml VialslStored In FreezerAOAC Technical Division On ReferenceMaterialsTrans- fatty Acid Reference MaterialMethods Used For AnalysislAOCS Cd 14c-94 GC MethodlAOCS Cd 14b-93 GC-IR MethodlAOCS Cd 14-61 IR MethodAOAC Technical Division On ReferenceMaterialTrans- fatty Acid Reference

4 MaterialDistribution Of Materiall15 Labs Volunteered To Do The analysis by oneOr More Of The MethodslEach Were Asked To Analyze Each Sample InDuplicate On Three Different DaysAOAC Technical Division On ReferenceMaterialTrans- fatty Acid Reference MaterialLaboratory ResponselGC Method:5lGC-IR Method:4lIR Method:5137 MethodLabNMeanStd. Dev. GC GC GC GC GC All Labs Acid Reference MaterialGCMethod AOCS Ce 1c-89 Margarine OilTrans- fatty Acid Reference MaterialGC-IRAOCS Method Cd 14b-93 Margarine OilMethodLabNMeanStd.

5 Dev. GC-IR GC-IR GC-IR GC-IR All Labs Acid Reference MaterialIRAOCS Method Cd 14-61 Margarine OilMethodLabNMeanStd. Dev. IR IR IR IR IR All Labs Acid Reference MaterialGC GC Method AOCS Ce 1c-89 Salad OilMethodLabNMeanStd. Dev. GC 76 GC 46 GC 26 GC 56 GC 36 All Labs 30 Acid Reference MaterialGC-IRAOCS Method Cd 14b-93 Salad OilMethodLabNMeanStd. Dev. GC-IR 46 GC-IR 56 GC-IR 66 GC-IR 36 All Labs 24 Dev.

6 IR 46 IR 26 IR 56 IR 16 All Labs 24 Acid Reference MaterialIRAOCS Method Cd 14-61 Salad Oil138 MethodNMeanStd. Dev. GC30 GC-IR24 IR30 Trans-Fatty Acid Reference MaterialTotal trans Between Lab VariationMargarine OilMethodNMeanStd. Dev. GC30 GC-IR24 IR30 Trans-Fatty Acid Reference MaterialTotal trans Between Lab VariationSalad Oil1520253030004000500060007000 Sig. 1 in A:\ (min.)Salad Oil182022243000400050006000700080009000 Sig. 1 in A:\ (min.)Margarine OilGC Method Advantages / DisadvantageslAdvantages Most oil refineries have GC's Simple sample preparation Capable of measuring individual fattyacids Useful for a wide range of sample typeslDisadvantages Difficult interpretation of data Long analysis timeGC-IR MethodAdvantages / DisadvantageslThis method is only intended for thedetermination of trans -octadecenoates139GC-IR MethodAdvantages / DisadvantageslAdvantages Fast Simple sample preparationlDisadvantages Uses carbon disulfide Data reduction difficult Not applicable to samples with

7 < 5% total transProject StatuslGC method appears to be the method of choicelResolution factor of 1 for trans -13 and oleic will be arecommended change in methodlA recognized expert, Dr. Ratnayake, Health Canadahas re-analyzed the sampleslAn expert review committee of six is reviewing thedata and will comment on where we should go fromhereWhy Use Reference Materials ?lGet everyone on the same pagelHelp everyone understand the variability ofmethods usedlUse with SPC techniques (pre-control) tocontrol the capability of methodsCargill WorldwideOilseeds ProcessingtUnited StatestCanadatVenezuelatBraziltArgentinatUnited Oilseeds Processing -Physical AssetsCrushing FacilityRefining FacilityPackaging Oilseeds Processing -Crushing FacilitiesBloomington, ILGuntersville, ALNorfolk, VACedar Rapids ,IAIowa Falls, IARaleigh, NCDawson, GAKansas City, KSSidney, OHDes Moines, IALafeyette, INSioux City, IAFayetteville, NCMemphis, TNWest Fargo, NDGainesville, GAWichita, Oilseeds Processing -Refining FacilitiesDes Moines, IAGainesville.

8 GASioux City, IAFayetteville, NCMemphis, TNWest Fargo, NDFullerton, CASidney, OHWichita, KS Vernon, Oilseeds Processing -Packaging FacilitiesChicago, IlGainesville, GASidney, OHFullerton, CAVernon, CARaw Materials ProcessedProteintCanolatCorntPeanuttSoyb eantSunflowertSpecialty Crops canola soybean sunflowerOiltCorntCottonseedtPalmtPeanut tSoybeantSunflowertSpecialty Oils canola sunflowertTallowLecithin sludgeSalad oilSoap stockSalad andcooking oil LiquidshorteningSalad dressingCooking oilOther fatty oilsShortening stock Shortening fat specialtiesCooking oilWaterAlkaliActivated earthH.

9 Catalyst2 DDDDDM argarineBlended oilsMargarine stockBleached oil Partiallyhydrogenated oilAlkali-refined oilCrude soybean oilDegummed oilSW and DSMonoglyceridesor tristearinHydrogenationnIn the presence of a catalyst, hydrogen gas is addedto the double bonds of fatty acidsnChanges the melting behavior of oils, converting oilsto semisolidsnReduces the iodine valuenImproves oxidative stabilitynIsomeric ( trans ) unsaturated fatty acids formedHHHHH2 HHCHHCHHCCHHCCCCHHCCCC141 Industry ActivityDevelopment of Low trans ProductsnOptimization of current processes Time exposed to high temperature Lower temperature during hydrogenation Hydrogen pressure Catalyst recyclingnDevelopment of new processes Time Temperature Precious metal catalystsnHigh temperature, high vacuum, steam distillationnCan produce isomeration.

10 Both positional andgeometricnRemoves Flavors and odors Free fatty acids Sterols Hydrocarbons PigmentsDeodorizationnMinimization of isomerization by optimizing Temperature Time Vacuum Stripping steam rateDeodorizationOther Industry ActivitiesProduction of Healthy Fats and OilsnPlant breeding High Oleic Sunflower High Oleic Soy Canola with unique propertiesnInteresterification Moving fatty acids to different positions in the triglycerides inthe fattRandom - chemical catalysistSelective - enzyme catalyzed Changes the melting properties of fats and oils Example: Interesterification of high melting fats with oils toproduce products with a variety of melting properties