Effect of calcium alginate coating on the cell retention and fermentation of a fungus-yeast immobilization system

Abstract Yeast cell leakage from the matrix is one of the reoccurring inconveniences of most yeast immobilization systems. Yeast biocapsules are a cost-effective, spontaneous immobilization system whereby yeast cells are attached to the hyphae of a filamentous fungus, creating hollow spheres that allow recovery and reutilization. In an attempt to prevent yeast cell leakage from the fungal matrix, we coated the yeast biocapsules with a 0.2% (w/v) alginate layer and evaluated yeast cell immobilization and the potential to ferment synthetic high sugar medium and grape must. We concluded that alginate coating prevents cell leakage from yeast biocapsules but hinders alcoholic fermentation. In grape must fermentations, alginate coating does not affect wine acidity but impacts concentrations of some volatile compounds.