Characterization of submicron emulsion processed by ultrasound homogenization to protect a bioactive extract from sea grape ( Coccoloba uvifera L.)

In this study, the stability of a submicron emulsion to protect an extract obtained from sea grape fruit (Coccoloba uvifera L.) was evaluated. Extract characterization by MS-HPLC revealed the presence of 3 anthocyanins (cyanidin 3-glucoside, malvidin 3-glucoside, and delphinidin 3-glucoside), the content of total phenols was 263.86 ± 1.86 mg gallic acid equivalent/100 g, with an antioxidant capacity determined by ABTS and DPPH of 128.95 ± 1.00 and 26.18 ± 0.60 μg Trolox equivalents/mL, respectively. A submicron emulsion (0.424 μm) by Ultrasound with monomodal distribution, stable over time and low viscosity (1.94 mPa s) classified as a shear-thinning fluid was obtained. The thermogravimetric analysis (TGA) demonstrated the stability of the C. uvifera extract in the emulsion, which is thermostable (212 °C). These emulsions can be added into a beverage as a nutraceutical, dried for later use as pills or incorporated in foods.

Keywords: Anthocyanins; Emulsion; Stability; Thermogravimetric analysis.