Lactic Acid Starter Cultures May Contain Milk
July 2009

Is this possible?
According to the Food & Allergy Anaphylaxis Network (FAAN) and Food Standards Australia & New Zealand (FSANZ), lactic acid starter cultures may contain milk. The most likely reason for this is due to the fact that many lactic acid starters or lyophilized probiotic cultures are produced by fermentation in dairy whey and casein growth media.

How can probiotics contain milk and soy?
Recently, a case was reported of an infant with documented cow's milk allergy who had anaphylaxis 15 minutes after ingestion of a probiotic preparation (Moneret-Vautrin et al., 2006). In a follow-up study, three probiotic preparations used widely in France were tested for the presence of cow's milk proteins to assess their potential to cause reactions in milk allergic individuals. Two of these were found to contain significant amounts of allergenic milk proteins. The manufacturers of these preparations indicated that the two products were grown on lactoserum proteins and casein-containing media. The third prepration, which tested negative for the presence of cow's milk protein, however, was grown in the presence of hydrolyzed soy proteins. These results indicate that probiotic preparations can be unsafe for individuals with severe allergies because of residual allergens (such as milk or soy) contained in the culture medium.

Is there a need for allergen management and allergen testing by probiotic providers?
The authors of this study suggested that serious efforts need to be made by probiotic providers to establish processing procedures that efficiently eliminate food allergens from culture media, to evaluate the residual allergen content in their culture preparations by specific allergen testing, and finally to indicate on the label the characteristics of the media used to culture the cells. Currently, there are no such measures in place. FACTS has obtained positive results for milk protein in lactic acid starter cultures commercially available in South Africa using the milk-specific ELISA test.

What else should be taken into consideration?
Finally, it is important to note that the fact that starter cultures and probiotic preparations may contain milk protein from the culture media does not preclude the possibility of the products tested in this study from being further contaminated with milk protein from the processing environment.

References:
USFDA (2006). Agency Response Letter - Objection Lyophilized Probiotic Cultures FALN No. 006 (Docket No. 2006FL-0287).
Moneret-Vautrin et al. (2006). Probiotics may be unsafe in infants allergic to cow's milk. Allergy, 61, 507-8.