Total polyphenol content and radical scavenging activity of functional yogurt enriched with dates
Both yogurt and dates are functional foods known for their valuable nutrients and health benefits. Therefore, this study was conducted to produce two types of date-enriched yogurts (20% wt/wt) to enhance their nutritive value and health benefits. While yogurt A was made with dates blended with milk, yogurt B was produced using small pieces of dates that were added to milk before fermentation. Both date-enriched yogurts were assessed for their physicochemical composition, total polyphenol content (TPC) and radical scavenging activity (RSA). The results showed that the addition of dates significantly enhanced carbohydrate, mineral and total solids contents of yogurts A and B (P < 0.05). Furthermore, dates significantly enhanced the TPC (34 and 37 mg GAE 100 g–1 for yogurt A and B, respectively) and the RSA (51% for yogurt A versus 57% for yogurt B) of date-enriched yogurts especially when dates were added as small pieces. During cold storage, both TPC and RSA decreased in all yogurt samples; however, they were maintained higher in date-enriched yogurts.
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