LAUSR

Abstract In a previous work, we obtained a betalain red dye from Beta vulgaris L. (beet) encapsulated with tetraethyl orthosilicate (TEOS) and studied its stabilities against changes of UV light, pH, and temperature. In the current research, we prepared betalain dyes from B. vulgaris L. and Myrtillocactus geometrizans (bilberry cactus), then we studied the effect of TEOS in the chemical structure by STEM and EDS analyses and its performance compared with a commercial dye FD&C Red 40. STEM showed an inorganic material surrounding an organic material and EDS of the inorganic part showed Si and O presence (dye encapsulation). Encapsulated dyes were more resistant to UV light than FD&C Red 40 and less resistant against pH and temperature changes. M. geometrizans had the highest nutraceutical content; it is not comparable in color appearance with FD&C Red 40, but its degradation is minimal, and in the yogurt model system, it is similar to the colorant of commercial strawberry yogurt. As a result, the red dye from M. geometrizans is a viable alternative to production in large scale.