Selective Adsorption of Rancid Ingredients in Extra Virgin Olive Oil for Enhancing Thermal Stability

Abstract

Selective removal of free fatty acid and chlorophyll while maintaining beneficial compounds is essential for expanding the use of extra virgin olive oil (EVOO) to the deep frying. In this work, we increased the thermal stability of EVOO by selective removal of rancid compounds with highly efficient adsorbent, (3-Aminopropyl)trimethoxysilane functionalized mesoporous silica with controlled pore size. The adsorption kinetics of rancid compounds into the mesoporous silica were quantitatively analyzed by Langmuir, pseudo-first and Poltorak model. The highest chlorophyll adsorption efficiency was shown in the pore size at 5.85 nm, suggesting that the interaction between the silica and the chlorophyll could be optimized at this point. In particular the amine-functionalized mesoporous silica showed drastically improved removal efficiency of FFA than the bare silica. Moreover, beneficial compounds like tocopherol and phytosterol maintained even after adsorptive removal. Based on this results, it is expected to attract the considerable amount of interest toward facile adsorptive refining process of EVOO using pore size controlled and amine-functionalized mesoporous silica.