Kinetika Oksidasi Termal Minyak Goreng Sawit Curah dengan Fortifikasi Vitamin A

Abstract

Vitamin A is one of an essential vitamin for human body. However, the deficiency of vitamin A is still in the spotlight not only in Indonesia but also in the world. Fortification of Vitamin A into cooking oil is one of solution to resolve this problem. In the other hand, the stability of vitamin A is an important thing to be studied. There are factors that influence the stability of vitamin A such as heat and oxygen. In this present study, the cooking oil that will be fortified has a difference of initial peroxide number i.e. 0.00; 3.99; and 8.99 meq active O2/kg oil. Besides that, the cooking oil that used has differences of temperature storage i.e. 60; 75; and 90°C. The objective of this study was to obtaining the model of thermal oxidation kinetics of cooking oil fortified with vitamin A levels are three types of different initial peroxide. The parameter that be used in this kinetic-study were the peroxide number, free fatty acid level using titrimetry analysis, and the level of vitamin A using HPLC. The result show that the formation of peroxide number and free fatty acid followed the zero order meanwhile the degradation of vitamin A followed the order 1. The reaction rate constant (k) and the energy of activation were calculated by using arrhenius equation. According to the result, the k-value from all of the parameter tends to increase by increasing of the time. The value of activation energy for each oxidation parameter were in ranges 44-64 kJ / mol for peroxide number, 48-64 kJ / mol for free fatty acid and 62-83 kJ / mol for degradation of vitamin A. According to the activation value that obtained, the fortified cooking oil with initial peroxide number 0.00 meq active O2/kg of oil is the most sensitive oil sample to the temperature in comparison with the other oil sample.