Detection of Oil Adulteration in Virgin Coconut Oil (VCO) Utilizing Chemometrics and Principal Component Analysis

Authenticationof virgin coconut oil (VCO) is imperative to protect the interests of the consumers. An investigation was carried out to distinguish VCO from coconut oil (CO), palm oil (PO) and liquid paraffin utilizing biochemical quality parameters, including fatty acid composition, and principal component analysis (PCA). Various oil blends of VCO: PO, VCO: CO (both in 10% increments), VCO:CO:PO and VCO: liquid paraffin and CO: liquid paraffin were prepared. The oil blends were analyzed for quality features, fatty acid composition and the data was analyzed statistically. Biochemical attributes such as total phenolic content (TPC), total flavonoid content (TFC), iodine value (IV) and saponification value (SV) and fatty acids like lauric acid, myristic acid, palmitic acid and oleic acid were influential parameters to distinguish the oil samples at various levels of adulteration. Samples could be classified even with the adulteration level of as low as 10%. Principal component analysis produced two components distinguishing various adulterated oil samples. Multiple regression analysis provided predictive equation models with high coefficient of determination (R-2) and could help in adulteration quantitation. Hence, this study demonstrated the efficacy of chemometrics approach in distinguishing VCO from possible adulterants like PO, CO and liquid paraffin.