Changes in water-soluble vitamins and bioactive compounds of cranberry (Cornus mas L.) nectar under different storage conditions

Cranberry is a fruit known for its high content of bioactive compounds, particularly polyphenols, flavonoids, and organic acids. In this study, physical and chemical changes were investigated during 6 months storage of cranberry nectar at different temperatures (4, 22, 30 and 40 °C). The water-soluble dry matter value remained approximately the same throughout storage. The decrease in the pH value during the preservation of the nectars increased the acidity of titration. Total phenolic content (TPC) and antioxidant activity (AA) increased during storage temperature. Storage period had little effect on TPC and AA values. Sugar, water-soluble vitamin and trans-resveratrol analyzes were analyzed by high performance liquid chromatography (HPLC). As a result of storage at high temperatures, the a* value in cranberry nectar decreased. The least change in color values was measured in cranberry nectars stored at 4℃. Cranberry nectars were initially rich in sucrose, but as storage progressed, both glucose and fructose amounts increased. The ascorbic acid content of cranberry nectar was detected to be high. Trans-resveratrol level in cranberry nectar dropped from 0.9518 mg L-1 to 0.6478 mg L-1 over 6 months of storage at 40 °C. The least loss in trans-resveratrol content was seen in cranberry nectars stored at 4 °C and 22 °C. TPC value decreased as storage temperature increased. While the AA value did not show any change depending on the storage time, it decreased with increasing storage temperature. The highest physical and chemical change during storage occurred at 40°C.