Techno-economic strategies for improving economic viability of β-carotene extraction using natural oil and supercritical solvent: A comparative assessment

Dunaliella salina microalgae is a third-generation feedstock that is both thermophilic and halophilic and can be used to produce nutritious food supplements such as beta-carotene. Although several techno-economic studies have been carried out to produce the pigment, most of them considered traditional synthetic chemicals such as hexane, acetone, and petroleum ether as solvents for extracting beta-carotene from D. salina. In this study, techno-economic assessment is carried out with the aim of producing food-grade products for human consumption via greener methods of D. salina cultivation, harvesting, and extraction. The techno-economic assessment of the extraction of beta-carotene and by-products using natural and edible corn oil and supercritical CO2 reveal that the processes are economically feasible, with a payback time of 5.9 y and 2.7 y (for corn oil and SC-CO2 methods), respectively. The ROIs for both methods are also positive, that is, 16.9 % and 37.1 %, respectively and greater than the prevailing interest rates in most countries. Sensitivity analyses show that the payback time is most sensitive to the yield of beta-carotene, its production output, and its selling price. This assessment shows that food-grade beta-carotene can be produced in bulk quantity from D. salina (as an alternative to other sources such as carrots, tomatoes, pumpkins, etc.) in order to satisfy the growing demands of nutritional markets.