Exploring carotenoid from Chlorella sorokiniana as a natural alternative to yellow artificial food dyes: Stability and application in model system.

This study investigated ultrasound-assisted extraction (UAE) using ethanol from Chlorella sorokiniana-derived carotenoids and encapsulation by co-crystallization. The carotenoid extract was quantified, identified, and evaluated for its encapsulation efficiency. Co-crystals were analyzed for FTIR spectra, morphology (SEM) and stability (moisture, water activity, carotenoid content, and color) over 90 days. Their potential as a natural dye in gelatin was also evaluated. UAE cavitation and ethanol affinity enabled the recovery of a lutein-rich extract, and its encapsulation efficiency of co-crystallization was 53 %. FTIR analysis of the co-crystals demonstrated characteristic functional groups of sucrose and carotenoids. SEM revealed a porous structure (2-20 μm) conducive to carotenoid entrapment. Over storage, moisture, and water activity increased, while carotenoid content decreased. Yellow color remained stable in co-crystals for 90 days but diminished in gelatin powder. The color of the ready-to-serve gelatin remained stable for seven days. Co-crystals can replace artificial dyes and sugar in gelatin.