The functional food industry requires an improvement of probiotic strain stability during storage, especially when they are stored at room temperature. In this study, the viability of freeze-dried Lactobacillus rhamnosus IMC 501(®) and Lactobacillus paracasei IMC 502(®) using different protective agents (i.e., glycerine, mannitol, sorbitol, inulin, dextrin, Crystalean(®)) was determined and compared with semi skimmed milk (SSM) control. No significant differences were observed between the tested protectants and the control (SSM) during storage at refrigerated conditions. During storage at room temperature, only glycerine was found to stabilize viability better than other tested substances.
Keywords: Lactobacillus paracasei; Lactobacillus rhamnosus; cryoprotectans; freeze-drying; prebiotics; probiotics.