Lycopene Extraction and Preparation of Its Nanoemulsion From Tomato Peel Using One Step Intensified Process Based on Microemulsion-Subcritical Water Technique.

Lycopene, a natural pigment with high antioxidant activity, is a main bioactive compound of the tomato processing waste. This study developed an intensified process based on lycopene extraction from tomato peel powder using microemulsion technique and its nanoemulsion (NE) preparation by subcritical water method. Four different emulsifiers, namely, Tween 20, Tween 80, saponin, and Arabic gum, were used and results indicated that using Tween 20, extracted lycopene NE with maximum lycopene content of 85.17 mg/kg, was prepared. Furthermore, saponin yielded lycopene NE with the minimum particle size (14.64 nm) and high zeta potential (-5.17 mV) values. Optimization process revealed that using a total amount of emulsifier mixture of 8.55 g, containing 53.53% saponin, resulted in lycopene NE with particle size, PDI, zeta potential, lycopene and carotenoid contents, and antioxidant activity 11 nm, 0.460, -6.47 mV, 86.19 mg/kg, 114.17 mg/kg, and 77.8%, respectively. The developed method in the present study offers a promising approach for developing functional foods enriched with lycopene.