Crude palm stearin: A green and fast fractionation method to obtain a natural oil structuring agent

Abstract

This work investigated the effect of temperature control on crystallization and centrifugation of the crude palm oil aiming to fractionate it into crude palm stearin (CPS) and crude palm olein (CPO), and to explore the potential use of CPS as a structuring agent for soybean oil.Fractionation was carried out using a slightly modified oil-binding capacity method, where the temperatures of 10, 15, 20, and 25 °C were applied at crystallization and centrifugation. Purity of CPO was demonstrated through differential scanning calorimetry. Further, CPS fraction was evaluated as structuring agent for soybean oil carrying out differential scanning calorimetry, small-angle controlled stress dynamic rheology, polarized light microscopy, and X-ray diffraction analyses. A strong influence of temperature was observed on the CPS and CPO fractions yields. The 25 °C was considered the best temperature for crystallization and centrifugation. The CPS in soybean oil at 50 % (w/w) developed a solid-like behavior due to dispersion of needle-like crystal organized in cluster. Thermal and rheological behavior, and crystal-like morphology and crystallinity observed are similar to the frequently repported on organogels, indicating its potential as a natural and minimally processed ingredient or additive for food and pharmaceutical formulations.