Background/Aims: While probiotic bacteria are successfully used in the treatment of ulcerative colitis, the effect of commercially available probiotic products is still controversial. Here, we study whether the number of living probiotic bacteria in yoghurts is altered by an interruption of the cold chain. Methods: Three commonly available probiotic yoghurts were kept at 4°C or put at room temperature (RT) for 6 h or 24 h. An aliquot of each yoghurt was applied on Man-Rogosa-Sharpe agar and incubated at 37°C for 48 h. Colony forming units (CFU) were counted by microscopy. Results: The first yoghurt, containing Lactobacillus johnsonii, showed a significant decrease in CFU after 6 h of storage at RT, which was further pronounced after 24 h. The number of CFU of the second yoghurt, containing Lactobacillus GG, was also decreased after 6 h and further diminished after 24 h at RT. From the third yoghurt, containing Lactobacillus acidophilus, only 53.8% of the CFU remained after 6 h at RT; after 24 h, only about one fourth of the CFU were found. Conclusions: Our data demonstrate that the number of living probiotic bacteria in yoghurt products decreases dramatically after exposure to RT. This represents an important information for consumers of such products.

1.
Guarner F, Malagelada JR: Gut flora in health and disease. Lancet 2003;361:512–519.
[PubMed]
2.
Beaugerie L, Flahault A, Barbut F, Atlan P, Lalande V, Cousin P, Cadilhac M, Petit JC, Study Group: Antibiotic-associated diarrhoea and Clostridium difficile in the community. Aliment Pharmacol Ther 2003;17:905–912.
[PubMed]
3.
Kruis W, Schütz E, Fric P, Fixa B, Judmaier G, Stolte M: Double-blind comparison of an oral Eschericia coli preparation and mesalazine in maintaining remission of ulcerative colitis. Aliment Pharmacol Ther 1997;11:853–858.
[PubMed]
4.
Rembacken BJ, Snelling AM, Hawkey PM, Chalmers DM, Axon AT: Non-pathogenic Eschericia coli versus mesalazine for the treatment of ulcerative colitis: a randomised trial. Lancet 1999;354:635–639.
[PubMed]
5.
Bibiloni R, Fedorak RN, Tannock GW, Madsen KL, Gionchetti P, Campieri M, De Simone C, Sartor RB: VSL#3 probiotic-mixture induces remission in patients with active ulcerative colitis. Am J Gastroenterol 2005;100:1539–1546.
[PubMed]
6.
Möndel M, Schroeder BO, Zimmermann K, Huber H, Nuding S, Beisner J, Fellermann K, Stange EF, Wehkamp J: Probiotic E. coli treatment mediates antimicrobial human beta-defensin synthesis and fecal excretion in humans. Mucosal Immunol 2009;2:166–172.
7.
Wehkamp J, Harder J, Wehkamp K, Wehkamp-von Meissner B, Schlee M, Enders C, Sonnenborn U, Nuding S, Bengmark S, Fellermann K, Schröder JM, Stange EF: NF-kappaB- and AP-1-mediated induction of human beta defensin-2 in intestinal epithelial cells by Eschericia coli Nissle 1917: a novel effect of a probiotic bacterium. Infect Immun 2004;72:5750–5758.
[PubMed]
8.
Mastrangeli G, Corinti S, Butteroni C, Afferni C, Bonura A, Boirivant M, Colombo P, Di Felice G: Effects of live and inactivated VSL#3 probiotic preparations in the modulation of in vitro and in vivo allergen-induced Th2 responses. Int Arch Allergy Immunol 2009;150:133–143.
[PubMed]
9.
Ukena SN, Singh A, Dringenberg U, Engelhardt R, Seidler U, Hansen W, Bleich A, Bruder D, Franzke A, Rogler G, Suerbaum S, Buer J, Gunzer F, Westendorf AM: Probiotic Eschericia coli Nissle 1917 inhibits leaky gut by enhancing mucosal integrity. PLoS One 2007;2:e1308.
[PubMed]
10.
Rasche C, Wolfram C, Wahls M, Worm M: Differential immunomodulating effects of inactivated probiotic bacteria on the allergic immune response. Acta Derm Venereol 2007;87:305–311.
[PubMed]
11.
Schillinger U: Isolation and identification of lactobacilli from novel-type probiotic and mild yoghurts and their stability during refrigerated storage. Int J Food Microbiol 1999;47:79–87.
[PubMed]
You do not currently have access to this content.