Freeze drying of beads containing yeasts

The cell viabilities of microorganisms during storage are of economic importance for probiotic dietary food and feed supplements. By combining granulation and freeze drying, dust free particles homogeneous in size and composition can be obtained. This will enable a good particle flowability, an easier dosage and a faster reconstitution of the product can be obtained. Encapsulator as a granulator to prill the yeasts suspension into liquid nitrogen and form monodispersed beads that will then be freeze dried.

Next to fermentation processes or transformation of foods, microorganisms such as Saccharomyces cerevisiae or lactic acid bacteria are of economic importance in the field of probiotic dietary food and feed supplements. These applications however require the preservation of cell viability during storage. By combining granulation and freeze drying, dust free particles, homogeneous in size and composition can be obtained. This will enable a good particle flowability, an easier dosage and a faster reconstitution of the product due to a higher surface area. Despite some challenges, freeze drying remains a convenient method of preserving yeasts, sporulating fungi and bacteria since the long term viability remains usually rather good and the requirements for storage and distribution of the strains are quite simple.This Note therefore aims to produce Saccharomyces cerevisiae particles as a model microorganism using the Encapsulator B-390 as a granulator to drip the yeasts droplets into liquid nitrogen and form beads that will then be freeze dried using the Lyovapor™ L-200.