EFFECTS OF PROCESSING AND STORAGE ON CHLOROPHYLL DERIVATIVES IN COMMERCIALLY EXTRACTED CANOLA OIL

This study characterizes the chlorophyll pigments present in canola oi l immediately after commercial extraction and following oil storage to determine the best storage conditions for analytical samples and to e xamine the changes that chlorophyll derivatives undergo during oil pro cessing and storage. Samples of pressed, solvent-extracted, crude and degummed canola oils, obtained from a commercial crushing plant, were stored for one month under four different conditions-in the freezer, i n a refrigerator and at room temperature both in the light and in the dark Chlorophyll derivatives (chlorophylls, pheophytins, pyropheophyti ns) were measured by high-performance liquid chromatography immediatel y after sampling and then on a weekly basis. The main pigments present in commercially extracted canola oil were pheophytin a, pyropheophyti n a, chlorophyll a and chlorophyll b. The ''a'' derivatives com prised 81 to 100% of total chlorophyll pigments in the fresh oil samples. Du ring degumming, the remaining chlorophylls were converted to pheophyti ns and pyropheophytins. During oil storage, exposure to light at room temperature affected the composition of chlorophyll derivatives as chl orophyll b was converted to pheophytin b and chlorophyll a was convert ed first to pheophytin a, then to pyropheophytin a.