Effect of Thermal Processing on Anthocyanin Degradation in Two Bilberry Jam Formulations

Fresh bilberries were processed into sugar and sugar-low jams at high temperatures (90, 95, 100 and 105 C) in order to follow degradation of total and individual anthocyanins. The greatest reten-tion of all examined compounds was observed in sugar-low jam prepared at 90 C for 5 minutes, while the greatest loss was detected in sugar jam prepared at 105 C for 30 min. Cyanidin-3-galactoside and cyanidin-3-glucoside were found to be the most stable, while delphinidin-3-arabinoside and petunidin-3-arabinoside were the least stable.