Survival lactobacillus bulgaricus

De Antoni et al. [1.23] demonstrated, that the addition of trehalose during freezing and thawing of two strains of Lactobacillus bulgaricus improved the survival rate differentially, but in both cases considerably. The samples (1 mL) were frozen at 18 °C/min to -60 °C and thawed to 37 °C at 15 °C/min. The solution consisted of distilled water, culture medium and 10 % milk with or without trehalose. It was shown, that after three freezingthawing cycles, milk alone resulted in a survival rate of 24 % or 65 %, while with trehalose this was can be improved to 32 % and 100 % respectively. The efficacy in the case of both strains was clearly different. De Antoni et al. suggested, that the efficiency of milk was related to its Ca2+ content, while the trehalose could replace water molecules in the phospholipids of the membranes. However no mention was made wether other sugar molecules in milk showed any effect. 

Hamann, W. T. and Marth, E. H. 1984. Survival of Streptococcus thermophilus and Lactobacillus bulgaricus in commercial and experimental yogurts. J. Food Prot. 47, 781-786. 

Lee, J.S., Cha, D.S., and Park, H.J. (2004). Survival of freeze-dried Lactobacillus bulgaricus KFRI 673 in chitosan-coated calcium alginate microparticles. J. Agric. Food Chem. 52, 7300-7305. 

The bacteria normally used in the production of yogurt, in particular Streptococcus thermophi-lus and Lactobacillus bulgaricus, are not expected to survive and overcome the intestinal tract and therefore are not considered probiotics. ... 

Teixeira, R, Castro, H., Malcata, EX., and Kirby, R.M. Survival of Lactobacillus delbruekii spp. bulgaricus following spray-drying, /. Dairy Scl, 78, 1025,1995. 

Vodnar, D.C. Socaciu, C. Rotar, A.M. StanUa, A. Morphology, ETIR fingerprint and survivability of encapsulated lactic bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) in simulated gastric juice and intestinal juice. Int. J. Food Sci. Technol. 2010, 45 (11),... 

Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus survive gastrointestinal transit of healthy volunteers consuming yogurt. FEMS Microbiol. Lett. 2005, 250 (2), 185-187. 

Teixeira, P. C., Castro, M. H., Malcata, F. X., Kirby, R. M. (1995). Survival of Lactobacillus delbrueckii ssp. bulgaricus following spray-drying. Journal of Dairy Science, 78(5), 1025-1031. 

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