Revisiting lycopene extraction: Caprylic acid-based emulsion for the highest recovery

In this study, we evaluated the caprylic acid-based oil-in-water (O/W) emulsion-assisted extraction of lycopene from tomatoes. Emulsion-assisted extraction was performed using two types of micron-sized O/W emulsions: (a) O/W emulsion with absence or (b) presence of 0.1% (w/w) of Tween 20 emulsifier. This green extraction technique was compared with the conventional method using soybean oil, tributyrin, and caprylic acid. The results show that caprylic acid, a green solvent, is significantly more effective for lycopene recovery than soybean oil and tributyrin. In the absence of an emulsifier, caprylic acid-based O/W emulsion significantly improved the lycopene content by 14.69 mg/g, corresponding to a 98.59% extraction efficiency at 50 ˚C. The capability of the proposed approach to lycopene recovery was explained in terms of lycopene affinity, the ability to swell the tomato cell, and some other standard parameters. In addition, caprylic acid has the significant advantage that once developed with the extracted lycopene can be used directly as a food additive.