Degradation of glycidyl esters in RBD palm oil as a function of storage conditions : Special Issue: Contaminants in fats and oils

Storage of oil samples in a refrigerator results in the degradation of glycidyl fatty acid esters (G-FE). In the present work the degradation rate for G-FE in RBD palm oil was determined at different temperatures with 0.4 mg/kg per month (5°C), 0.3 mg/kg per month (10°C), 0.2 mg/kg per month (15°C), 0.1 mg/kg per month (−20°) and 0.0 mg/kg per month (20°C). The crystallization process was identified for RBD palm oil as reason for this phenomenon. Isothermal differential scanning calorimetry measurements show that this process delivers enough energy to cleave the epoxy bonding of the G-FE (33.7 J/g (5 and 15°C) and 41.5 J/g (10°C)).