Main content area

Protection of probiotic bacteria in a synbiotic matrix following aerobic storage at 4 °C

Chaluvadi, S., Hotchkiss Jr., A.T., Call, J.E., Luchansky, J.B., Phillips, J.G., Liu, LS., Yam, K.L.
Beneficial microbes 2012 v.3 no.3 pp. 175
Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus reuteri, acids, aerobic conditions, bacteria, calcium, cold storage, crosslinking, dietary supplements, fructooligosaccharides, health promotion, inulin, probiotics, shelf life, storage conditions
The survival of single strains of <i>Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus,</i> and <i>Lactobacillus reuteri</i> was investigated in synbiotics that included 10 mg/ml of fructo-oligosaccharides, inulin and pectic-oligosaccharides in an alginate matrix under refrigerated (4 °C) aerobic storage conditions. When the matrices were cross-linked with calcium (45 mM), 10<sup>2</sup>-10<sup>3</sup> cfu/ml of <i>L. acidophilus</i> and <i>L. reuteri</i>, and 0-10<sup>3</sup> cfu/ml of <i>B. breve</i> and <i>B. longum</i> survived refrigerated aerobic storage for 28 days. Following refrigerated storage, acetic (3-9 mM), butyric (0-2 mM), propionic (5-16 mM) and lactic acids (1-48 mM) were produced during the growth of probiotics in BHI broth at 37 °C, suggesting their metabolic activity after storage was stressed. When calcium cross-linking was not used in synbiotics, the matrix remained more gel-like after inoculation when compared to the calcium cross-linked matrix. At least 10<sup>7</sup> cfu/ml of probiotic bacteria survived after 21 days of storage within these gel-like alginate matrices. Significantly higher levels of <i>B. breve</i>, <i>L. acidophilus</i> and <i>L. reuteri</i> were obtained from the synbiotic matrices supplemented with fructo-oligosaccharides, inulin and pectic-oligosaccharides compared to alginate alone. <i>B. longum</i> survival was the same (~7 logs) in all gel-like synbiotic matrices. These results show that synbiotics protected probiotic bacteria and extended their shelf-life under refrigerated aerobic conditions. Synbiotics represent a viable delivery vehicle for health-promoting bacteria.