SYRINGE NEEDLE-BASED SAMPLING COUPLED WITH LIQUID-PHASE EXTRACTION FOR DETERMINATION OF DISTRIBUTION AND DEGRADATION OF CAROTENE IN CARROTS

Abstract

A method using syringe needle-based liquid-phase extraction technique with liquid chromatography analysis was utilized to determine the distribution of carotene in carrots. Optimization of extraction parameters was carried out smoothly: 100 ?L 2-propanol as extractant to extract ?-carotene for 20 min. The distribution of ?-carotene was carefully detected and illustrated using a 3D model after dividing the carrot sample into 6 parts. The variation of ?-carotene concentration during storage under different temperatures indicated that -5? was more suitable than 20? for carotene preservation. The drastic degradation of ?-carotene under -20? may be caused by interval freezing and thawing of carrot samples for carotene extraction. As this novel extraction method consumes much less organic solvent, less time and simpler steps than traditional solvent extraction, it has great potential for practical usage, such as analyzing the distribution and variation of analyte concentration during a long period of storage time.