DOBI & Carotene Content of Crude Palm Oil - UV Vis Spectroscopy

This application note determines the Deterioration of Bleachability Index (DOBI) and carotene content of crude palm oil using UV/VIS spectrophotometry. To find out more, please proceed to download the method below.

How is crude palm oil tested spectrophotometrically?

Crude palm oil is an edible oil extracted from the pulp of palm fruits. The quality of this oil depends on many factors including the ripeness of the palm fruit, storage conditions, and the time between harvesting and production. DOBI is a procedure designed to test the quality of crude palm oil and this can be performed using UV Vis spectrophotometry. DOBI is the numeric ratio of the spectrophotometric absorbance at 446nm to that at 269nm:

I_DOBI=A₄₄₆/A₂₆₉,

Therefore, the absorbance of crude palm oil samples can be measured at these two fixed wavelengths and a numeric value which indicates the quality can be calculated. Different values indicate the quality of the crude palm oil, with a value above 3.24 meaning that the sample is of excellent grade.

Crude palm oil is reddish in color due to the presence of carotene. This is also an important indication of quality and the concentration of the palm oil can be measured using the absorbance at 446nm.

The UV7 Excellence spectrophotometer is used alongside LabX^TM PC software in this application note to provide an automatic calculation of the DOBI value and carotene concentration. Proceed to download the application to receive detailed method instructions.