Quality characteristics and antioxidant activity of yogurt dressing containing black currant extract

Abstract

This study was carried out to investigate the quality characteristics and antioxidant activity of yogurt dressing prepared with different amounts (0, 5, 10, 15, and 20%) of black currant (Ribes nigrum L) extract. All samples were evaluated for chemical composition, pH, viscosity, sugar content, color, organic acid content and antioxidant activity. Our findings revealed that with increasing amounts of black currant extract in yogurt dressing, the moisture, crude protein and crude lipid contents decreased. The pH and viscosity gradually decreased, whereas the sugar increased with increase in black currant extract. Further, the lightness (L) value decreased, while the redness (a) and yellowness (b) values increased with increase in added black currant extract. Among the organic acids, the contents of citric acid, malic acid, succinic acid and acetic acid increased, while that of tartaric acid and lactic acid decreased with increasing levels of added black currant extract. The total polyphenol and total anthocyanin contents were 5.90-245.97 mg/100 g and 0.62-190.09 mg/100 g, respectively. In addition, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-thylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities significantly increased with increase in added black currant extract.