The aim of the study was to evaluate the effect of hot air convective drying (HACD), microwave vacuum
drying (MWVD) and their combination (HACD + MWVD) on the drying kinetics, colour, total polyphenols,
anthocyanins antioxidant capacity and texture of frozen/thawed blueberries. Drying resulted in reduction
of total polyphenols content and antioxidant capacity (69 and 77%, respectively). The highest content of
total polyphenols was noted after HACD at 90 C. Lower air temperature and prolonged exposure to
oxygen resulted in greater degradation of polyphenols and antioxidant capacity. Drying processes caused
a significant decrease (from 70 to 95%) in the content of anthocyanins. The highest content of
anthocyanins and the strongest antioxidant capacity was found in blueberries dried using HACD at
90 C + MWVD. Among drying methods, HACD at 90 C + MWVD satisfied significant requirements for
dried fruits i.e. short drying time and improved product quality.
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