A Comparative Study Concerned with Differential Scanning Calorimeter (DSC) and Fatty Acid Profile Methods to Detect the Adulteration of Sunflower Seed Oil in Extra Virgin Olive Oil

Subject Areas : Microbiology

A.  Pashaei ¹ (دانشجوی کارشناسی ارشد مهندسی کشاورزی - علوم و صنایع غذایی، واحد شهر قدس، دانشگاه آزاد اسلامی، تهران، ایران)
F.  Shovakhi ² (استادیار موسسه تحقیقات فنی و مهندسی کشاورزی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران)
M.  Fahimdanesh ³ (استادیار گروه علوم و صنایع غذایی، واحد شهر قدس، دانشگاه آزاد اسلامی، تهران، ایران)
F.  Badei ⁴ (دانشیار موسسه تحقیقات فنی و مهندسی کشاورزی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران)
A.  Rahmani ⁵ (استاریار پژوهشکده غذایی و کشاورزی، پژوهشگاه استاندارد، کرج، ایران)

Received: 2016-02-21 Accepted : 2016-02-21 Published : 2016-03-20

Keywords: Adulteration, DSC, Extra Virgin Olive Oil, Fatty Acid Profile, Sunflower oil,

Abstract :

Introduction: Extra virgin olive oil represents the popular source of oil in the Mediterriancountries. The price of extra virgin olive oil is increasing rapidly in the world market, due tomany factors namely special organoleptic and health attributes. Therefore this popular oilmight be subjected to adulteration. In this research, the application of Differential ScanningCalorimeter (DSC) and fatty acid profile methods to detect the adulteration of sunflower seedoil in extra virgin olive oil has been studied.Materials and Methods: Refined sunflower seed oil was added to extra virgin olive oil atdifferent portions (5, 10, 15 and 20 percent) and the thermal analysis of the samples wereperformed using DSC and the fatty acid composition of the samples were determined by GCapparatus.Results: The results of the thermal analysis showed that the addition of sunflower seed oilcreated significant changes in cooling and heating thermograms of DSC. The enthalpy, onsetand maximum temperature of major crystallization peak for at least 10% adulteration and theenthalpy and maximum temperature of minor melting peak for 5% adulteration indicatedsignificant differences as compared to the extra virgin olive oil (P<0.05). The results alsoindicated that the major fatty acids in the mixture with at least 5% sunflower seed oil showedsignificant differences as compared to extra virgin olive oil (P<0.05). The quantities ofbehenic and linoleic acids in the mixtures of 15 and 20 % added sunflower seed oil to olive oilindicated higher amounts than those defined as standard values.maximum limit of standardvalue.Conclusion: The DSC method might be evaluated as a valuable method to detect theadulteration of refined sunflower seed oil in extra virgin olive oil however this method has itslimitations regarding the percent of added oil.