Assessment of Moringa oleifera Lam. Seeds Potential as an Adsorbent Material for Soybean Oil Bleaching

Abstract

During the refining process of vegetable oils, the removal of pigments occurs in the bleaching stage, in which oil-adsorbent agents are used. Although various types of adsorbent materials are commercially available, alternative bleaching agents are being constantly investigated to increase the efficiency of this step. This work used seeds of Moringa oleifera Lam. in natura and in the form of activated charcoal to remove chlorophyll from soybean oil. The techniques used for this purpose were infrared with Fourier transform (FTIR), thermogravimetric analysis (TGA), chlorophyll by ultraviolet-visible (UV-VIS) spectroscopy, titratable acidity, gas chromatography with a flame ionization detector (GC-FID), and direct infusion by electrospray ionization mass spectrometry in positive ion mode (ESI(+)-MS). The results obtained showed that the defatted seeds of Moringa did not have the potential to remove chlorophyll from the oil. Activated charcoal produced from seeds, on the other hand, was effective as a bleaching agent, removing 97.53% of the chlorophyll content of the treated soybean oil. Besides, the use of coal obtained from Moringa seeds did not significantly change the composition of fatty acids, therefore, the use of coal as Moringa seeds is indicated. As a result, the activated charcoal from Moringa seeds has the potential to be used during the refining process of soybean oil.