Antioxidant Properties of a Yogurt Beverage Enriched with Salal (Gaultheria shallon) Berries and Blackcurrant (Ribes nigrum) Pomace during Cold Storage

Aqueous extracts (20% w/w) of dried berry fruits and skins were used as sources of phenolic compounds to fortify yogurt beverages. The total phenol and anthocyanin content of the reformulated yogurts were determined, and the antioxidant properties were compared to plain yogurt (C) during storage at 4 degrees C for a total period of four weeks. Yogurt beverages fortified with salal berry (SB) extracts contained higher amounts of phenolic compounds (>69.9 mu g GAE/mL) and anthocyanins (>19.12 mg C3G/L) compared to drinks supplemented with blackcurrant pomace (BC) extract (>50.13 mu g GAE/mL and >10.80 mg C3G/L respectively). Storage affected the stability of anthocyanins, whereas total phenol content remained unaffected. Yogurts with SB displayed the highest antioxidant capacity followed by samples with BC, which is attributed to the radical scavenging effect of the bioactive compounds present with antioxidant properties. The antioxidant capacity of the yogurt beverages fortified with fruit extracts was maintained during cold storage. Findings of this study indicate that SB and BC pomace can be used as functional ingredients to increase the antioxidant potential of yogurt beverages.