Viability and enzymatic activity of bifidobacteria in milk.

Bifidobacterium breve NCFB 2258, Bifidobacterium bifidum NCFB 2715, Bifidobacterium longum ATCC 15707, Bifidobacterium angulatum ATCC 27535, and Lactobacillus acidophilus N2 were evaluated for viability and beta-galactosidase and alpha-galactosidase activities under conditions of refrigerated and frozen storage in reconstituted NDM. beta- and alpha-Galactosidase activities were variable. Bifidobacterium angulatum 27535 exhibited much greater enzymatic activities than those of the other strains. All strains demonstrated culture and enzyme stability upon refrigerated storage in fermented and unfermented reconstituted NDM. Bifidobacteria were significantly less tolerant of low temperature storage than was L. acidophilus N2.