Microencapsulation of Probiotic Bacteria with Alginate and Prebiotic and Evaluation of Survival in Ice Cream

摘要

The aim of this study was to evaluate the influence of prebiotics, resistant starch and acacia gum,incorporated into alginate beads, on the survival of microencapsulated bacteria in ice cream over a period of180 days of storage at -18 °C. For microencapsulation of Lactobacillus acidophilus NCFM andBifidobacterium lactis BI-04, 1.0% sodium alginate containing 0.1% of each freeze-dried culture and 2.0% ofprebiotic (acacia gum or resistant starch) was atomized in a 0.1 M calcium chloride. Dairy ice cream wasproduced with the following composition (w/w): 59% of pasteurized milk, 17% cream, 8.0% skim milkpowder, 12% sucrose, 3.0% glucose, 0.5% guar gum and carrageenan, 0.2% emulsifier, and 0.3% vanillaflavor. The mixture was ripened for 24 h at 5 °C and microencapsulated probiotics were added beforefreezing in order to achieve approximately 10~8 cfu.g~(-1). As controls, ice cream with free probiotics andmicroencapsulated probiotics without prebiotics were produced. Microencapsulation and the addition ofacacia gum and resistant starch did not significantly (p > 0.05) influenced the survival of probiotic cultures.At the end of 180 days of storage, L. acidophilus and B. lactis population remained above 107 and 108 cfu.g~(-1),respectively, even in ice cream with free probiotics. The microencapsulation had no effect on sensorialacceptability (p > 0.05) of probiotic ice cream. The results indicate that dairy ice cream can be considered asuitable vehicle for incorporating probiotic microorganisms.