Effect of long-term storage on viability and acceptability of lyophilized and spray-dried synbiotic microcapsules in dry functional food formulations

Abstract

The viability of probiotic bacteria and acceptability of dry shelf stable synbiotic foods were studied during long-term storage at room temperature. Synbiotic microcapsules were prepared using Pleurotus florida extract as prebiotics and Enterococcus faecium as probiotic, through lyophilization and spray-drying methods. These microcapsules were added to two different dry food matrices, an Indian traditional dry food powder (sattu) and a malted health drink, and were evaluated for the viability of probiotic bacteria and organoleptic properties during storage. Encapsulation by both the methods was found to enhance probiotic survival in dry food matrix during storage. There was 4 log unit reduction in lyophilized formulation as compared to 3 log unit reduction in spray-dried form, after 15 weeks of storage. Thus, spray-dried form of synbiotic fortification was significantly more stable (P < 0.05) than lyophilized form. Survivability of probiotics in dry food matrix is inevitable to overcome the disadvantages of liquid-based cold stored formulations.