Study Of Extraction,Separation And Photostability Of Paprika Pigments

Methods for the determination and extraction as well as primary purification of the functional components, consisted of paprika pigments and capsaicinoids from paprika were studied in this paper. For completely separating the two components, supercritical CO₂(SC-CO₂) was used when the paprika was as the material. And molecular distillation(MD) was done when the paprika oleoresin was as the material. Yellow pigments mixture(β-carotene, β-cryptoxanthin ester and zeaxanthin esters) and capsanthin esters were obtained by silica gel column separation and their photostability was compared with paprika pigments.The determination of paprika pigments was done by National Standard of the People's Republic of China, and the ratios of red pigments and yellow ones(R/Y) were determined by reference of experiential formula. The high performance liquid chromatographic conditions of determining the content of capsaicinoids were as following: The relative standard difference was 0.51% ,the range of recovery ratio was 97.79% to 102.35%。By single factor selecting experiments and orthogonal test, the best technics of extracting paprika oleoresin was: temperature 50℃,time 0.5h and the solvent (hexane) volume was 9 times than the weight of the paprika. The oleoresin yield was 5.03%, color value was 155.49,R/Y was 1.257,the content of capsaicinoids was 0.846%. After purification by 50% ethanol solution, the oleoresin color value was 167.91, R/Y was 1.362 and the content of capsaicinoids was 0.537%, the recovery ratio was 91.95%.The operation of using SC-CO₂ to separate the two components was: temperature was 40℃,extraction parameters were at 15MPa,2.5h,35kg/h;sepration parameters were at 12MPa and 6MPa in the first extractor and the second extractor respectively. The obtained pigments without capsaicinoids color value was 316.66, R/Y 2.753;the capsaicinoids color value was 41.88, R/Y was 0.729,content was 1.268%.The technics of MD was as following: pressure 0.1 Pa, input flux 1.5².0g/min, distillation temperature 160℃. The material paprika oleoresin color value was changed from 157.70 to 178.37, R/Y0.933 to 0.918, the content of capsaicinoids 0.510% to 0.With or without sunlight, capsanthin esters had the best photostability and its degradation ratio was 50% for 4 days and less than 0.5% for 3 months . In these two conditions, the stability of the paprika pigments was very worse.