The Protective Effect of Inulin and Resistance Starch in Lactobacillus Casei Microencapsulation in Beet Root Juice

Combination of prebiotics fructooligosaccharides (Beneo-95, Beneo-Orafti) and resistance starch (Firbersol-2, ADM) was reported to have a synergistic effect in the guts. Inulin as prebiotic could be applied to enhance viability of probiotic. Inulin and resistant starch at concentration of 1% (w/v) and 1.5% (w/v) were added into sodium alginate to form bead by extrusion method to encapsulate Lactobacillus casei. Viable cell number of L. casei in free form was added at concentration of 1.32E+07 ± 5.66E+05def CFU/mL at first day and decrease 5.20E+06 ± 7.00E+05f CFU/mL after 6 weeks storage at 4°C. Calcium alginate (2% w/v) encapsulated probiotic has better survival rate that it decreased (week 0 = 8.00E+07 ± 2.55E+07bc CFU/mL and week 6 = 7.57E+07 ± 5.86E+06bc CFU/mL) while Calcium alginate (2% w/v)-inulin (1% w/v)-resistant starch (1.5% w/v) encapsulated probiotic showed the least reduction (week 0 = 5.45E+07 ± 7.07E+05bcd CFU/mL and week 6 = 4.47E+07 ± 1.05E+07cde CFU/mL). This result showed that encapsulation with the addition of inulin and resistant starch at 1% (w/v) and 1.5% (w/v), respectively can significant increases rate of survival of probiotics which in beet root juice. pH of juice which contain free cell was decreased after week 6 (5.756667 ± 0.012g), while the addition of inulin and resistant starch at 1% (w/v) and 1.5% (w/v) has showed slightly increased (week 0 = 5.963333 ± 0.046ef and week 6 = 6.19 ± 0.01c). The acidity (%) of the free cell increased to (week 0 = 0.117104 ± 0.005ab and week 6 = 0.156139 ± 0.01a) while the 1% (w/v) inulin and 1.5% (w/v) resistant starch decreased (week 0 = 0.13512 ± 0ab and week 6 = 0.129115 ± 0.005ab). Viability reduction in simulated gastric fluid (SGF) test of free cell after 2 hours was (week 0 = 4.20E+06 ± 2.65E+05a CFU/mL and week 6 = 7.00E+05 ± 1.25E+05b CFU/mL), addition of inulin and resistant starch at 1% (w/v) and 1.5% (w/v) has lower (week 0 = 1.27E+08 ± 1.65E+07a CFU/mL and week 6 = 8.67E+07 ± 1.53E+07b CFU/mL). Free cells in simulated intestinal fluid test showed decrement (week 0 = 5.13E+06 ± 1.29E+06b CFU/mL and week 6 = 2.20E+06 ± 6.24E+05b CFU/mL), while 1% (w/v) inulin and 1.5% (w/v) resistant starch decreased (week 0 = 9.7E+08 ± 1.11E+08b CFU/mL and week 6 = 6.4E+09 ± 4.74E+09a CFU/mL).