Benign recovery of carotenoids from Physalis alkekengi L.var. francheti through supercritical CO2 extraction: Yield, antioxidant activity and economic evaluation

Abstract

Benign recovery of carotenoids has been carried out on the calyx of Physalis alkekengi var. francheti by means of supercritical CO2 (SCCO2) extraction. The influences of extraction pressure, temperature and particle size on the time-dependent carotenoids yield are fully investigated and kinetically analyzed by using the hot-sphere model. The highest carotenoids yield recovered in 200 min is 15.96 mg/g raw sample, indicating that the calyx may be of great interest as valuable raw resources for the extraction of carotenoids. sThe SCCO2 extract has exhibited good antioxidant capacity as verified by radical-scavenging activity test results. The manufacturing cost (COM) for SCCO2 extraction of carotenoids from the calyx has been evaluated for scaling-up to the pilot plant at 40 MPa and 50 °C and a particle size of 0.114 mm. The effects of extraction capacities, labor wages, CO2 price and calyx-purchasing cost on COM have been analyzed. When using a capacity of 2 × 500 L and an extraction time of 60 min, the estimated specific COM can be US$ 687.96/t calyx or US$ 65.27/kg carotenoids, respectively. These calculation results turn to suggest that SCCO2 extraction is economically feasible to produce carotenoids form the herbal calyces.