freezing at 20 C may be economically advantageous, at the laboratory
and industry levels, for these foods.
The results for a- and b-carotene, b-cryptoxanthin, lutein, lycopene
and zeaxanthin, do not suggest the storage conditions used
(70 C, in the dark, under nitrogen and in an organic solution similar
to the HPLC mobile phase) affect the carotenoids studied in the
mass concentration range 0.05–5 lg/ml for up to six months. The
only exception was lycopene at the lowest mass concentration
(0.05 lg/ml), which was stable for only six weeks. This knowledge
reduces analysis time by 85% and costs for standards by 94%.