Carotenoid analysis of foods is inherently difficult due to a
large number of naturally occurring carotenoids, highly variable
composition of foods, wide ranges of carotenoid concentrations,
and isomerization and degradation of carotenoids prior to and
during analysis (7, 8). Errors associated with chromatography
are minor (9), but errors from extraction procedures are
potentially significant (7). With a variety of published methods
available, it is difficult to select appropriate protocol for
standardization between laboratories.