Influence of Drying Methods on the Chemical Characteristics of Irvingia gabonensis Kernel Oil and Oil Cakes

Optimizing the drying conditions prior to processing Irvingia gabonensis kernels into vegetable oil is a crucial step in preserving the quality of the final product.This study aimed to evaluate the influence of two drying methods (airdrying and oven-drying) on the quality parameters of the extracted oil and the resulting oil cakes.The results showed that oven-dried kernels exhibited a significantly lower moisture content (0.58 ± 0.01%) compared to air-dried kernels (2.44 ± 0.01%).The oil yields were 62.71 ± 7.65% for air-dried kernels and 74.68 ± 9.60% for oven-dried ones.The oils extracted from air-dried and ovendried kernels presented similar values, with peroxide indices of 0.13 ± 0.03 and 0.14 ± 0.01 meq O 2 /kg, acid values of 0.79 ± 0.08 and 0.98 ± 0.04 mg KOH/g, and saponification values of 179.55 ± 3.97 and 178.15 ± 9.92 mg KOH/g, respectively.The oil cakes obtained from air-dried and oven-dried kernels showed, respectively, protein contents of 19.06 ± 0.36% and 18.97 ± 0.62%, ash contents of 8.58 ± 0.41% and 7.68 ± 0.12%, potassium contents of 2.30 g/100 g and 1.95 g/100 g, calcium contents of 0.79 g/100 g and 0.82 g/100 g, sodium contents of 0.73 g/100 g and 0.64 g/100 g, phosphorus contents of 0.68 g/100 g and 0.62 g/100 g, magnesium contents of 0.40 ± 0.06 g/100 g and 0.33 ± 0.03 g/100 g, and identical iron contents of 0.01 ± 0.001 g/100 g.Statistical analysis revealed no significant differences between the two drying methods for most of the oil quality parameters and the chemical characteristics of the oil cakes.Nevertheless, air drying at 25˚C better preserves most of the chemical parameters of both the oil and the oil cake, whereas oven drying at 60˚C better preserves phosphorus.