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This work compared the mechanisms of adsorption of carotenes from hybrid palm oil onto two kinds of bleaching earths widely used by industrial refiners (acid-activated and neutral). First, it was performed a deep characterization of adsorbent surfaces: acid activated adsorbent showed micropore volumes twice larger than the neutral. FTIR analysis of adsorbent after adsorption demonstrated that active site was Si-O-Si for both adsorbents. However, comparison of peak shapes suggested distinctive interactions between adsorbent/adsorbate for each adsorbent. Latterly, an extensive kinetic and equilibrium study was performed. Kinetic data were in accordance with pseudo-first and pseudo-second-order models. Adjusting to the intra-particle diffusion model evidenced more than one mechanism controlling the adsorption process. Equilibrium data demonstrated adsorption is only favorable at low carotene concentration at liquid phase for acid adsorbent (lower than 1 mg/ mL). For neutral adsorbent, it was not clearly observed a favorable region with the studied conditions. The acid adsorbent could adsorb more carotenes per adsorbent weight than neutral. Finally, neutral adsorbent showed higher heterogeneity of interaction between adsorbate and adsorbent than the acid, especially at low adsorbent coverages.

Interspecific hybridization of oil palms (E. guineensis × E. oleifera) was initially exploited to provide disease resistance and, consequently, increased oleic acid content. Besides the growing importance of this cultivar to the market, there is little information about this oil’s properties. In this context, this study aimed to determine a comprehensive physicochemical and thermal characterization of hybrid palm oil (HOPO) compared with the better-known African palm oil (APO). Differences in the distribution of fatty acids, carotenoids, and tocols were observed. Minor differences in density and viscosity were found between the oils, with no relevance for the materials’ processing design. Nevertheless, HOPO showed unique crystallization behavior, which potentially can affect industrial operations, such as fractionation. HOPO did not present the two thermal characteristic regions of APO, attributed to olein and stearin fractions. The HOPO demonstrated a decrease in the melting point of more than 3 °C in relation to APO, and a reduction in the crystallization point of more than 6 °C. Furthermore, besides the higher content of unsaturated fatty acids, HOPO was more stable than APO due to a higher antioxidant content. These results could be useful to establish operation conditions for processes using palm oil from hybrid oil palm.

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