The Effect of Physical Refining on Palm Vitamin E (Tocopherol, Tocotrienol and Tocomonoenol)

Chiew Wei Puah, Yuen May Choo, Ah Ngan Ma and Cheng Hock Chuah

This study reports the effect of physical refining on palm vitamin E including α−tocopherol, α−, γ− and δ−tocotrienols as well as α−tocomonoenol. A method using HPLC with fluorescence detector using normal phase silica column is described. An isocratic elution with n-hexane/THF/2-propanol (1000:60:4, by vol.) as mobile phase was used. The structure of the α−tocomonoenol was determined using gas chromatography coupled with mass spectrometry. The composition of the vitamers were α−tocopherol (14–17%), α−tocotrienol (22–24%), γ−tocotrienol (49–53%), δ−tocotrienol (6–7%) and α−tocomonoenol (3%) throughout the physical refining. The concentration of all vitamers in crude palm oil was 1273±18 ppm. The concentrations of all vitamers in degummed palm oil, bleached palm oil and deodorized palm oil were 1134±20 ppm, 1095±18 ppm and 1029±18 ppm, respectively. This method provides fast and valuable information with minimal analysis time and no sample pre-treatment.