The gene MT3-B can differentiate palm oil from other oil samples.

The practice of blending cheap palm oil with more expensive oils is currently rampant owing to the increased global price of oil and the price gap between types of oils. This adulteration poses a serious threat to the trade of edible oil and negatively affects consumers. The aim of this study was to identify the presence of palm oil as an additive in more expensive oils using a PCR-based technique. A taxon-specific gene, MT3-B, was found by searching the GenBank database. MT3-B showed high oil palm (Elaeis guineensis Jacq.) specificity, low intraspecies variability, and a low copy number. On the basis of the MT3-B sequence, conventional and real-time PCR assays were established to detect palm oil contamination by amplifying an amplicon of 109 bp. The lowest copy number that the conventional PCR method could detect was five haploid copies; the limit of detection (LOD) for the real-time PCR assay was estimated to be five haploid copies. Experimental results demonstrated that the PCR-based methods were specific, sensitive, and reliable and could successfully detect the palm oil component of mixed oil samples.