Microwave-assisted drying of lactic acid-producing bacteria

Microwave-assisted drying techniques were investigated for their suitability regarding preservation of the two probiotic model strains Lactobacillus paracasei ssp. paracasei F19 and Bifidobacterium animalis ssp. lactis INL1.
Microwave freeze drying showed comparable results as conventional freeze drying with regard to survival, storage stability and handling properties. However, the efficiency of the microwave process was considerably higher. Microwave vacuum drying of a foam structure was superior to unfoamed vacuum- and microwave vacuum-dried cultures.