Encapsulation of Hibiscus sabdariffa L. anthocyanins as natural colours in yeast

Hibiscus sabdariffa extracts, a rich source of anthocyanin, were subjected to encapsulation in yeast cells. An encapsulation yield (EY) of 208 μg/100 mg of cells and an encapsulation efficiency (EE) of 27%, were reached after optimisation of the ratios (0.5 g wet yeast cells for 5 ml of anthocyanin extracts at 1 g·L−1) and with 10% of ethanol. The storage stability of encapsulated pigments was investigated in water and buffer pH 1.5 at 5 & 37 °C for 10 days and 90 °C for 30 min. The percentage of loss of colour was determined by colourimetry assays. The microparticles made of yeast with or without heat treatment exhibited different protecting effects (P