Extraction And Application Of The Profiles Of Fatty Acid And Triglycerides In Vegetable Oils And Animal Fats

This paper discussed the methods of distinguishing vegetable oils (VOs), animal fats(AOs) and illegal cooking oils (ICO) according to fatty acids and triaglycerides of four Vosand four AOs combined with statistical analysis methodsThe FA profiles of8kinds of vegetabl oils(VO) and animal fats(AF) were analysed byGC. The fifteen main FAs were choosen as variables to perform canonical discriminantanalysis both when all samples were divided into8groups and into3groups, the methodestablished could identify soybean oil(SO) adulterated with8%lard or5%chiken fat(CF) andrap oil(RO) mixed with10%lard or10%CF, as well as the illegal cooking oil. The methodthat the relative degree of unsaturation were combined with trans FA and the odds weresuccessfully applied to identify RO with8%lard or10%CF and ICO except3#. This methodwas on the assumption that the belongs of samples were known.The composition of sn-2FA were analysed by GC and TLC. The nine FAs were choosento proform the same canonical discriminant analysis. This method could only identify ROadulterated with8%lard or5%chiken fat(CF) and the illegal cooking oil exactly. The plotwere drawn basing on palmitic and stearic. VO was distributed intensively away from AF.When the content of palmitic was more than2.42%or the content of stearic was more than0.7%, the sample was regarded as ICO. This method could identify vegetable oil with3%lard, SO with3%CF, RO with10%CF, and all ICO.The profile of triaglycerides(TGs) of oils and fats were got by RP-HPLC/ELSD.45kinds of TGs were handmade confirmed by retention time, peak shape, peak of the blends.These TGs were used to canonical analysis in the same way. This method could only beapplied to identify identify SO with1%lard or3%CF, but could be not suitable to detectpure fats and oils, as well as ICO.In a word, the discussed methods based on fatt acids were more simple and feasible. Thecontents of palmitic and stearic were used to detect ICO most successfully and most simple.