LAS CRUCES, NM Plant pigments are an important source of non-toxic compounds for use as food or cosmetic coloring agents. In addition to their known nutritional value, the red pigments in Capsicum (chile pepper) are important as sources of non-toxic red dyes; the red pigments are added to many processed foods and cosmetics to enhance their appearance. Certain varieties of Capsicum annuum can be "extracted' to isolate red-colored xanthophylls, an important economical source of red pigments that can replace carcinogenic synthetic red dyes.
Until now, the common method for extracting red pigments from dried fruit of Capsicum has used hexane as the extraction solvent. A noteworthy new research study from New Mexico State University presents a process for efficient extraction of these red pigments using "green chemistry". The method recovers 85% or greater of the pigmented carotenoids from dried Capsicum and reduces the hazardous waste and environmental risks associated with traditional extraction methods.
In New Mexico, the economic value of a chile crop includes the value of the fruit harvested as a fresh green product and a dried red product often harvested later in the season. Current extraction processes are limiting; red pigment can only be recovered from American paprika varieties or other mild cultivars. According to a team of researchers from the Department of Plant and Environmental Sciences at New Mexico State University, if extraction of the red pigments could be achieved separate from the capsaicinoids, then a wider range of red-fruited cultivars could be used, including those with important values as fresh green crops.
The scientists created a "green chemical" method that generates an oleoresin from dried Capsicum fruit with virtually the same carotene and xanthophyll composition as the hexane extraction method. The report appears in HortScience. Mary A. O'Connell, corresponding author of the study, explained; "If a
|Contact: Michael W. Neff|
American Society for Horticultural Science