Abstract
Separation and quantification of trans-resveratrol in blueberry extracts were achieved using high performance liquid chromatography (HPLC). Trans-resveratrol in blueberry juice was found to be at a high level of 16.60 ± 0.19 µg/mL. This antioxidant polyphenolic compound was also quantified, in two brands of blueberry powder, to be 236.4 ± 7.5 µg/g or 269.9 ± 5.7 µg/g. Degradation of trans-resveratrol was observed in standard solutions and in blueberry samples (juice and powder extracts). It was found that degradation of trans-resveratrol was more severe when it was exposed to room light at room temperature. Therefore, it is advisable to store blueberry juice at 4°C in the dark, and consume it within 1–3 days in order to benefit from adequate intake of the antioxidant in the juice.
ACKNOWLEDGMENT
This work was supported by a Discovery Grant of Natural Science and Engineering Research Council of Canada.