Continuous production of highly bioavailable lycopene nanodispersions via subcritical ethanol extraction and in-line mixing

Abstract

This study aims to prepare Z-isomer-rich lycopene nanodispersions via ethanol extraction at higher temperature and pressure conditions (i.e., subcritical conditions) from tomato powder and continuous dispersion using an in-line swirl mixer. Firstly, the effects of ethanol extraction conditions, i.e., temperature (40–160 ℃), time (10–60 min), and pressure (10–30 MPa), on lycopene recovery and Z-isomerization were investigated. The extraction at > 120 ℃ significantly enhanced lycopene recovery and Z-isomer ratio of lycopene in the resulting extract. Subsequently, the resulting extract liquid (ethanol solution) was continuously dispersed in water containing polyglycerol fatty acid ester using an in-line mixer, and successfully prepared Z-isomer-rich (approximately 70%) lycopene nanodispersions. This production process is economical and highly compatible with the food industry due to using a safe extraction solvent and continuous production capability. In the future, it will be necessary to investigate the biological activities of the resulting lycopene and perform scale-up verification of this process.