Potential authentication of re-esterified triacylglycerol-type omega-3 oils using multivariate analysis of lipid profiles.

This study aimed to authenticate re-esterified triacylglycerol (rTG)-type omega-3 oils prone to adulteration with fatty acid ethyl ester (FAEE)-type oils via hierarchical cluster analysis (HCA) and principal component analysis (PCA) of their lipid profiles. A total of 104 rTG-type omega-3 oil samples, consisting of seven authentic (two commercial and five laboratory-made), 60 adulterated, and 37 unauthenticated commercial samples, were analyzed for their acylglycerol, FAEE, and total EPA/DHA contents. Type 1 authentic samples contained higher triacylglycerols (TG) (63.0-86.3 wt%), lower diacylglycerols (DG) (8.1-31.5 wt%), and no FAEE compared to type 2 authentic samples (36.9-62.1 wt% TG, 9.4-36.9 wt% DG, and 14.9-27.3 wt% FAEE). HCA and PCA differentiated authentic samples from adulterated samples, although type 2 samples were closer to adulterated samples. Both analyses showed that 30/37 commercial samples exhibited higher similarity in lipid profiles to authentic samples than to adulterated samples, indicating their potential for authentication.