Evaluation of the nutritional, in vitro protein digestive and bioactive characteristics of a quinoa-based protein beverage

This study investigated the nutritional, digestive properties and potential health effects of a quinoa-based protein beverage (QBPB). In terms of nutrition, QBPB demonstrated superior nutritional estimates than a commercial oat-based liquid beverage, with a higher essential amino acids/total amino acids ratio (40.69 %), essential amino acids/non-essential amino acids ratio (68.62 %), amino acid score (87.50 %), essential amino acid index (89.58), and predicted biological value (85.95). QBPB exhibited a high <i>in-vitro</i> protein digestibility (89.21 %) and protein digestibility-corrected amino acid score (0.78), which was close to ideal protein. After digestion, QBPB showed enhanced antioxidant activity with an IC₅₀ for ABTS radical scavenging activity of 2.15 mg/mL, and ACE inhibitory activity with an IC₅₀ of 0.19 mg/mL. Overall, QBPB showed promising protein quality and health effects. This study provides a significant basis for exploration of the nutritional and health benefits of quinoa-based functional foods and for promotion of quinoa in food production.