Enhancing iron bioavailability and bioactive stability in sweet-sour beetroot sauce through liposomal vitamin C

This study investigated the efficacy of vitamin C (vit. C) encapsulation in liposomes for improving iron bioavailability and preserving bioactive compounds in sweet-sour beetroot sauce. Five sauce formulations were developed: a control (S), two sauces fortified with varying concentrations of free vit. C (SC1: 31.4 mg/100 mL and SC2: 62.8 mg/100 mL), and two sauces incorporating liposome-encapsulated vit. C at corresponding concentrations (SE1: 21 mL liposome /100 mL and SE2: 42 mL liposome/100 mL). Physicochemical analyses included color, pH, and rheological measurements. The total phenolics, flavonoids, antioxidant activity (DPPH and reducing power), vit. C and betalains were assessed. In vitro bioaccessibility assays were conducted for both betalains and iron. Sensory evaluation determined consumer acceptability. Results demonstrated that encapsulation significantly enhanced iron bioavailability, with SE2 exhibiting an 8.83% bioavailability compared to 4.00% in the control. Similarly, betalain bioaccessibility increased from 17.83% in the control to 29.33% in SE2. Encapsulation also demonstrated a protective effect on other bioactive compounds. Sensory analysis confirmed the palatability of all sauce formulations. These findings suggest that vit. C encapsulation presents a promising strategy for developing iron-fortified functional foods with enhanced nutritional value and consumer appeal.