Partitioning of phytonutrients in fractional crystallization of crude palm oil

Abstract: Dry fractionation of the crude palm oil (CPO) can be employed to concentrate more phytonutrients in the crude palm olein (CPOL) prior to the chemical refining. This work focuses on evaluating the kinetics of fractional crystallization of CPO as affected by minor components from different CPO qualities. The crystal growth behavior of CPO was evaluated in situ using focused beam reflectance measurement (FBRM) and the mechanism of crystallization determined using Avrami model showed high nucleation rate at the beginning of crystallization which decreased with time (n = 1). The CPO, olein and stearin fractions were characterized for fatty acid compositions, triacylglycerol (TAG) compositions and principal component analysis (PCA) has been used to establish a new method for the detection of the phytonutrients partitioning. Statistical analysis revealed that the separation of samples with different crystallization kinetics was achieved using the triglyceride profiles of both CPO and olein fraction, proved to be more discriminating than those of the fatty acids. The results revealed that the partitioning of tocopherol and tocotrienol in the crude olein fraction was strongly influenced by the disaturated TAG (SSU) and DAG content of the CPO. In particular, the content of POS and POP of the olein fraction. However, this was not the case with carotene partitioning. In conclusion, the enrichment of tocols via fractional crystallization proposed reduction in olein quality which can compromise fractionation efficiency. This discoveries suggest new insights relating to the partitioning behaviour of phytonutrients during fractional crystallization of CPO.