As Americans learn more about the beneficial bacteria called "probiotics" and their role in healthy digestion and immunity, research has begun to focus on applying probiotics in grain-based foods. Yet there’s no need to wait on the research findings. Grain-based foods companies already may tap into the marketing opportunity by adding probiotics — and prebiotics — to their products. Some are already on the market.

Pro? Pre? What’s the difference? A joint group of the Food and Agriculture Organization of the United Nations/World Health Organization defined probiotics as "live microorganisms, which when administered in adequate amounts confer a health benefit on the host." Prebiotics are defined as "nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth of one or a limited number of bacterial species in the colon, such as Bifidobacteria and Lactobacilli, which have the potential to improve host health."

Prebiotic fibers may come in such forms as resistant starch, inulin and fructooligosaccharides (FOS). They generally aid beneficial probiotic bacteria such as Bifidobacteria and Lactobacilli already in the human gut. The heating involved in the baking process may kill probiotics, making it a challenge to apply probiotics, but not prebiotics, to grain-based foods.

Americans showing more interest

Americans might have trouble spelling the names of bacterial species, but they are interested in digestive health. Research released earlier this year by Tate & Lyle P.L.C., London, showed 62% of U.S. consumers find the concept of products that promote a healthy digestive system appealing, which compared with 54% of consumers in the United Kingdom, 59% in France and 68% in Germany.

The findings also showed 67% of U.S. consumers were receptive to a range of products that help boost the immune system through an optimum combination of vitamins, minerals and fibers. Comparable figures among overseas consumers were 69% in the United Kingdom, 65% in France and 73% in Germany.

Adding to the appeal of prebiotics is their ability to support structure/function claims.

"With prebiotics labeled as a ‘structure/function’ claim, we do not see any limitation in this respect, as long as the food processor fully understands the scope of the claims and develops a protocol in order to apply a prebiotic in a standardized fashion," said Fred S. Kaper, president of Sensus America L.L.C., Monmouth Junction, N.J. He defined dosage or storage as a workable standardized approach.

Examples of structure/function claims that might be used with probiotics include how they promote a healthy microflora, help maintain an effective immune system and foster regularity, said Cliff Caron, vice-president of bakery product development for Lallemand, Inc., Montreal.

Prebiotic fibers are some of the key ingredients used in the new Enrich service from Tate & Lyle. The service seeks to assist food and beverage manufacturers in creating products that are packed with additional nutrients but retain the same quality taste as the regular brand. Enrich focuses on three main areas: digestive health and immunity, obesity and weight management and children’s health.

Tate & Lyle is in the process of launching a resistant starch made from soluble corn fiber, said Doris Dougherty, a senior food scientist. Studies show the soluble fiber may be fermented, and it will give prebiotic effects.

"We are studying in more detail what those can be," Ms. Dougherty said. "(The ingredient) can be labeled as corn syrup, and it’s a lot like working with corn syrup in terms of functional properties."

Tate & Lyle’s resistant starch is designed to be more heat stable and more shear stable than other resistant starches on the market, which works well in cracker applications, Ms. Dougherty said.

National Starch Food Innovation, Bridgewater, N.J., also offers a line of resistant starch ingredients under the Hi-Maize brand. The company runs a web site at that tracks research studies done on resistant starch.

Pointing in a new direction was a study published in The Journal of Nutrition in May 2005. The research was led by Dr. Richard Le Leu of the Department of Medicine at Flinders University of South Australia-Bedford Park with participation from National Starch and Australia’s CSIRO Health Sciences and Nutrition. It demonstrated that the combination of natural RS2 (a form of resistant starch) from high-amylose corn and the probiotic bacteria Bifidobacterium lactis increases apoptosis (programmed cell death) of cells damaged by carcinogens by more than 30%.

The study also confirmed that natural resistant starch reduced the pH in the large intestine, boosted the growth of Lactobacilli and Bifidobacteria and increased the presence in the gut of short-chain fatty acids (SCFAs), including butyrate, the preferred energy source for healthy colon cells.

Examining the effects of inulin

Many research studies focus on the prebiotic effects of inulin and FOS.

Extracted from chicory roots, Frutafit inulin from Sensus America is a prebiotic having Generally Recognized as Safe (GRAS) food ingredient status in the United States and traditional fiber status in Canada. Research suggests that 5 grams of inulin a day stimulates growth of helpful gut bacteria, which leads to a healthy digestive system, said Connie Lin, applications manager for Sensus America.

Vitaal Flora brand bread produced in The Netherlands contains at least 5 grams of Frutafit inulin per 100-gram serving. The bread earned a healthy digestive claim in that country. Sensus carried out the research to create this new product at the request of and in cooperation with Bake Five, one of the five largest bakery organizations in The Netherlands. Vitaal Flora bread is sold by the Albert Heijn food retailing group.

Recognizing the benefits of the formulation, The Netherlands Nutrition Board, Ministry of Health stated: "Consumption of three slices of Vitaalbrood Flora per day supports a well-balanced gut flora composition and colonic function by selectively stimulating the growth of Bifidobacterium."

The board added, "For individuals with already high numbers of Bifidobacteria, there may be no additional bifidogenic effect, but fermentation of extra inulin still produces higher levels of short chain fatty acids that are potentially beneficial."

A paper on research done at the University of Reading in the United Kingdom and in The Netherlands reported that in vivo demonstrations show inulin doses ranging from 5 to 8 grams per day had a prebiotic effect in healthy humans. The European Journal of Clinical Nutrition accepted the paper for publication.

Sensus America works with North American food and beverage manufacturers on applications involving Frutafit inulin and Frutafit fructooligosaccharides (FOS).

"We already have successful products in the market and expect many more," said Pam Galvin, vice-president of sales and marketing for Sensus America. "We have extensive research and expertise in this area and will seek approval of similar health claims by the Food and Drug Administration."

Food manufacturers need to consider taste, affordability and appropriate functionality when choosing a particular prebiotic for bread, bars, cereal, pasta or other grain-based foods, emphasized Mr. Kaper of Sensus.

"In addition, the efficacy may be determined by the selection of a particular type of inulin/oligofructose in relation to the matrix of the food product, the release of the material in the colon and the storage conditions of the food product," he said.

Another ingredient supplier, Orafti Active Food Ingredients, Malvern, Pa., has scientific research to back up its prebiotic fibers. At last year’s Orafti Research Conference in Boston, speakers talked about how the large intestine may act as a "second brain" in maintaining the body’s defenses against harmful bacteria and viruses and also help in the control of energy intake and in the metabolism of fat and glucose. Research work done in Belgium showed feeding Beneo oligofructose to obese rats stimulates a series of complex signals from the gut that helps in the control of food intake and body weight.

Prebiotic effects on probiotics are documented, too. Danisco USA, Ardsley, N.Y., offers a prebiotic, Litesse polydextrose, which complements its line of Howaru probiotic cultures. Randomly linked glycosidic linkages mean that Litesse resists hydrolysis by human digestive enzymes. After ingestion, it passes intact into the colon where it is partially fermented by the colonic microflora. It selectively stimulates the growth of Bifidobacteria and Lactobacillus.

Colon simulation work done in collaboration with Glenn Gibson, Ph.D., a professor at the University of Reading in the U.K., confirms the stimulation of Bifidobacteria at each stage of colonic fermentation.

Probiotic applications take hold

While not nearly as common as prebiotics in grain-based foods, probiotics are starting to make appearances. In December 2006, Flowers Foods, Inc., Thomasville, Ga., added SnackAway peanut butter wafers to its Mrs. Freshley’s line of "betterfor-you" snacks. The bars contain probiotics, and the carton provides information to consumers about probiotics.

Kashi, La Jolla, Calif., a division of The Kellogg Co., added the probiotic bacteria Lactobacillus to its Vive cereal, which the company promotes for its digestive benefits.

Probiotics may be added after the baking process is complete. Ms. Dougherty of Tate & Lyle said resistant starch could be added to a cracker itself and then a probiotic could be applied to the creamy filling inside.

Mr. Caron of Lallemand said probiotics could go into chocolate toppings or coatings, yogurt toppings or coatings or oil-based coatings. Formulators would need to work with environments that are friendly to the live probiotics.

"Something with low water activity, a high protein level, a low sugar level and a higher fat level," he said.

Food manufacturers once had vague reactions to the potential for probiotic and prebiotic applications, but that trend is changing, Mr. Caron said.

"I think now we’re going to see really rapid growth with more products coming into the marketplace," he said.