Composite Enzyme-Assisted Aqueous Extraction of Tiger Nut Oil: Microencapsulation Optimization and Stability...

Tiger nut oil (TNO) is rich in unsaturated fatty acids, but it can deteriorate due to oxidation during storage. In this study, the stability of TNO was improved by optimizing composite enzyme-assisted aqueous enzymatic extraction (AEE) and coupling it with microencapsulation. Under the optimized AEE conditions, the oil yield reached 22.5 ± 0.21% (w/w). The extracted TNO contained 73.24% unsaturated fatty acids and exhibited acceptable physicochemical properties. To stabilize the oil, TNO was microencapsulated using maltodextrin and whey protein as wall materials. The optimal formulation (maltodextrin:whey protein = 3:2, wall-to-core ratio = 1:10, soy lecithin = 1.8%) achieved an encapsulation efficiency of 79.87%. During open storage at 25 ± 2°C for 30 days, the rate of increase in the acid value (0.3 vs. 0.8 mg/g/day) and peroxide value (0.2 vs. 0.5 mmol/kg/day) was reduced, while the antioxidant capacity was higher than that of unencapsulated TNO. These results demonstrate an integrated, green extraction and scalable microencapsulation strategy that enhances the storage stability of TNO. PRACTICAL APPLICATIONS: The optimized, enzyme-assisted, composite aqueous extraction process is a green, nutrient-preserving method of producing tiger nut oil (TNO) that addresses the low yield of traditional aqueous extraction. Maltodextrin-whey protein microcapsules with an encapsulation efficiency of 79.87% significantly reduce TNO oxidation during storage. This enables TNO to be used on a large scale in the food and cosmetics industries, solving the key issue of its poor stability.