Optimization of coconut oil extraction through microwave drying and enzymatic–ultrasound treatment with emphasis on yield and quality parameters

Abstract Coconuts are a valuable industrial, economic, and nutritional resource, widely used in the production of food, cosmetics, and biofuels. The objective was to evaluate the extraction of coconut oil from a hybrid derived from the crossbreeding of the Tall Caribbean x Dwarf Malayan varieties using heat transfer and enzymatic technologies. Physicochemical parameters were determined for the fresh pulp and coconut oil obtained using drying methods (forced air oven and microwave) in combination with the extraction process. The enzymatic extraction process of coconut oil was then optimized using Lipozyme® TL IM lipase (1.0, 2.0, and 3.0% w/w) with different water contents (15, 25, and 35% w/v) and ultrasound reaction times (30, 60, and 90 min), using response surface methodology. The fatty acids present in the methods with the highest yield were identified and quantified by GC/MS. The coconut copra had 45.65 ± 1.34% moisture, 1.06 ± 0.08% minerals, 62.45 ± 1.15% fat and oil, 4.93 ± 0.15% protein, and 0.48 ± 0.01% crude fiber. The drying methods did not show significant differences in oil yield. Microwave drying followed by non-heating extraction (MOFF) showed the best yield (62.80 ± 4.92%) with 0.06 ± 0.01% moisture, 0.20 ± 0.01% lauric acid, density of 0.92 ± 0.01 g/mL, pH of 5.31 ± 0.28, L* of 2.72 ± 0.49, a* of -0.08 ± 0.03, b* of -0.24 ± 0.11, and stability of 1.32 ± 0.05 years. The response surface methodology optimized the extraction conditions at a water content of 35%, lipase at 1.0%, and 30 min of ultrasound reaction for yields greater than 70% and improved oil quality. The main saturated fatty acids were lauric acid (C12:0) and long-chain fatty acids (C14:0 and C16:0) with values of 46.18 and 46.62, 21.15 and 22.24, 10.17, and 10.02 g/100 g of extracted coconut oil for MOFF and enzyme-optimized, respectively. Coconut oil from the Tall Caribbean x Dwarf Malayan hybrid represents a high yield agroindustrial alternative with a favorable fatty acid profile for applications in nutrition and cosmetics.