Markus Lipp

Kristie Laurvick

Functional foods represent a business opportunity that shows no sign of slowing down. But as these foods grow in popularity, one of the key categories—probiotics—is at a crossroads. Growing consumer recognition bodes well for food products incorporating probiotic ingredients, but future growth may be threatened by ongoing issues surrounding ingredient claims and an absence of publicly available standards for identity and quality.

Utilizing probiotic ingredients poses a host of scientific challenges. These include the difficulty in differentiating individual probiotic strains, as well as to the ability of microorganisms to survive complex processing and storage conditions (not to mention their ability to survive within the body itself). The array of complicating factors unique to probiotics makes public standards especially important for these ingredients—particularly as inexperienced manufacturers begin to formulate with them.

Central to the safety of a probiotic ingredient is its identity. Most safety studies and the clinical trials to support any purported health claim are based on the strain level. Of course, consumers do not think in terms of genus, species, and strain (taxonomy) when purchasing these products. Advertisements tout either (generically) “probiotics” or, for example, “Lactobacillus” (this is likely as specific as one would expect to see). However, the specific strain of Lactobacillus in the advertised product may be different on a functional level from every other strain of Lactobacillus. While consumers may not be thinking in those terms, it is the responsibility of the food industry to confirm the genetics of the strain, and to appropriately connect the results of clinical trials (i.e., the function of those strains) to the ingredient they are selling. Not doing so may put consumers at risk of purchasing ingredients that do not work in the way they expect, and may also put the entire probiotics industry at risk of being seen as promoting materials that do not meet apparent claims.

Additionally, any claimed effect of probiotics is also directly related to dosage. This triggers the need to count the number of live organisms present enumeration). All probiotic strains and products are not created equal; the number of organisms required for any effect will depend on the strain used. Counting probiotics organisms first requires growing them in their preferred conditions. Each strain may have its own very specific “preferred conditions,” including essential nutrients and ideal temperature. Hence, tests for enumeration are developed at a minimum specifically for a species and, ideally, down to strain level.

Probiotics are in wide use, and most companies using these ingredients are able to meet these challenges. However, as the use of probiotics expands to a growing array of food products well beyond the more traditional types of dietary supplements and yogurt/dairy foods, public standards that provide identification and enumeration methods, in addition to other quality specifications, can provide a powerful tool for manufacturers. Independent public standards can provide an important mechanism to verify that what is on the market is what it is purported to be, and can help keep honest players in the industry competitive.

Through the Food Chemicals Codex (FCC), an international compendium of standards for the identity, quality, and purity of food ingredients, the U.S. Pharmacopeial Convention (USP) is beginning to develop these standards. In December 2011, USP proposed an appendix to be included in FCC titled Microbial Food Cultures Including Probiotics. This resource covers key considerations, including identification and enumeration, to take into account when utilizing probiotic ingredients, and also addresses topics such as intended uses in food, safety, regulatory status, and purity of probiotics. Via FCC, USP intends to develop more specific individual standards at the species (and perhaps strain) level for probiotics, similar to what it provides for other food ingredients. This will require a close partnership with the food industry.

USP is seeking to ascertain the needs of industry as it embarks on this work so standards can be developed in the most useful, practical way. How to proceed in this effort will be the central focus of a joint USP-IFT workshop, which will be held May 9–10, 2012, in Rockville, Md. More information is available at

Generating meaningful public standards will be a cooperative effort of industry, academia, regulators, and others. While standards development work for probiotics will pose some significant challenges, it offers much opportunity. Grounding the hype of probiotics with transparent science can help preserve the future of these ingredients.


Markus Lipp, Ph.D., ([email protected]), a member of IFT, is Director of Food Standards and
Kristie Laurvick, M.S., ([email protected]), a member of IFT, is Scientific Liaison for USP, Rockville, Md. 20852.