Freeze-Drying of the Black Currant Juice

The effect of drying temperature of the black currant juice on the retention of vitamin C and anthocyanins content as well as drying kinetics in the freeze-dried process, has been studied. Non clarified, black currant juice was freered on plates in the layer of 15 mm thick until the temperature of -30 °C in the thermal center of sample has been reached. Plates with frozen layers of juice were subject of freeze-drying process at 5 different temperatures of the heating plate (20, 30. 40, 50 and 60 °C). Studies of the retention of vitamin C and anthocyanins after, drying were carried out. freeze-drying of black currant juice should be carried out at the temperature not higher than 40°C to preserve content of vitamin C and anthocyanins.