Working with Probiotics
Feb. 1, 2012
by Laurie Gorton
Just as dietary fiber readily incorporates into baked foods, so can probiotics. The better-for-you bacteria that support gut health also support market appeal, and the frequency of consumption of baked foods makes them excellent candidates for probiotic additions. Proving this point, new breads, wraps and nutrition bars containing probiotics are already on the market.
Thanks to common foods such as yogurt that contain active bacterial cultures, consumers already know the value of beneficial microbes and how they fit into their busy lives. “Probiotic products are well-recognized by consumers and reach a new segment of the market,” observed Joanie Dion, technical representative, R&D, for Institut Rosell, a division of Lallemand, Montreal, QC.
The popularity of probiotic foods is easy to understand, given that 38% of US consumers currently manage a digestive problem, said Kayla Polzin, PhD, principal scientist, probiotics, Cargill, Wayzata, MN, quoting a recent report. Digestive health benefits rank high with many shoppers. “Consumers continue to desire more fiber and whole grain, but there has also been an increase in the desire to incorporate probiotics into their diets,” Dr. Polzin said.
Americans currently spend more than $1 billion each year on probiotic-based products, according to Ganeden Biotech, Mayfield Heights, OH. Mike Bush, the company’s vice-president, business development, noted more than 50 different foods and beverages now on the market use Ganeden probiotics. “We have tested hundreds of different foods,” he said. “Our general feeling is that products that are consumed on a regular basis make good candidates for probiotics to be incorporated into daily lifestyles.”
Today, many people seek answers to their health-and-wellness concerns in the foods they purchase and consume. They view active cultures of beneficial bacteria, or probiotics, as aiding the digestive function with specific potential for alleviating irritable bowl syndrome, diarrhea, constipation, immune system problems and more. For example, clinical studies found chocolate supplemented with probiotics to be useful in stress management.
But to achieve such benefits, probiotics must be consumed daily because they move constantly through the digestive system. A 2005 study by Australian researchers found that Lactobacillus acidophilus and L. casei, two typical probiotics, survived in the human gut but dissipated when consumption stopped, with none left two weeks later.
“We recommend 1 billion colony-forming units (cfu) per serving,” Ms. Dion said. This measures viable cells, unlike direct microscopic counts where all cells, living and dead, are tallied. Bacteria are extremely small, and 1 g of the pure culture easily contains 25 billion to 50 billion cells. “And there are no regulations in the US about level of use,” she added.
In the digestive system, Mr. Bush explained, probiotic microbes produce L-plus lactic acid, which lowers pH, thus making the gut less hospitable to destructive microorganisms. Probiotics use proteins and simple sugars as their food source.
Delivering probiotics to consumers, however, requires the formulator to consider the application and its effect on the microorganism.
“The limiting factors in adding probiotics to food are primarily about keeping the bacteria alive,” Dr. Polzin said. “Probiotics are best supplied in short-shelf-life refrigerated foods.” Recent advances in encapsulation extend applications to nonrefrigerated foods. “For baked foods and snacks, the best applications have low water activities and shelf lives of less than six months,” she said.
Ms. Dion cautioned that probiotics should be added after baking or heat shock, or else they must be protected by encapsulation. “But we have strains that are resistant to baking, Bacillus subtilis R0179, which can be used in bread and baked products.”
Cargill offers single strains or combinations of probiotic cultures of Bifidobacterium lactis, L. johnsonii (formerly L. acidophilus), L. paracasei and L. rhamnosus as concentrated, frozen cultures.
Lallemand’s roster of probiotic cultures includes L. rhamnosus, L. helveticus, Bif. longum and Saccharomyces boulardii in specialized strains developed for human nutrition by Institut Rosell. The company patented the Probiocap microencapsulation technology that protects probiotics in food applications. Applications such as chocolate, granola bars and peanut butter are typical, according to Ms. Dion.
Probiotics are becoming more formula- and process-friendly, according to Mr. Bush, and Ganeden recently patented its Ganeden-BC30, a strain of Bac. coagulans, specifically for baked foods, cereals and other grain-based foods. It withstands high heat, freezing, mechanical stress, high pressure and long-term storage. “As long as the process is not too brutal, you can easily add it and then forget about it throughout the manufacturing cycle,” he said. “Bread and cookies fit into this spectrum.”
Applications dictate the conditions of use. “Some allow the probiotic to be mixed into the blend, but others may require encapsulation,” Mr. Bush said. “It’s a case-by-case situation, and formulators should use the supplier’s R&D support to decide where best to put the probiotic into the product.”
That’s how Ganeden worked with Orlando Baking (see “Real-life bakery experience” on Page 72). “Water activity was the big concern,” Mr. Bush said. “Since we did not want to alter the baker’s manufacturing process, we looked at it very carefully to see where the best place was to add Ganeden-BC30.”
In general, the less the processing, the better the results. “Applications that have really long bake times or high water activity are less suited to probiotics than something drier,” Mr. Bush said.
Coated and drizzled
Keeping probiotics viable during processing through distribution usually requires some sort of protective environment. Confectionary coatings do this job well, and such coatings are often custom-built by the coating manufacturer working with a probiotics supplier. Chocolate must meet federal Standards of Identity that stipulate permitted ingredients, but no such regulations apply to confectionery coatings. Formulators can use nonstandard ingredients to deliver flavor and functional benefits.
“Confectionery coatings have long been used as a carrier to deliver innovative flavors or unique flavor combinations to an increasingly discerning and competitive marketplace,” said Kelly Austin, vice-president of technical sales, Clasen Quality Coatings, Madison, WI. “Confectionery coatings can turn a product from dull to delectable.” Uses range from drizzle designs and inclusions to panning, moulding and full enrobing. In drop form, they can enhance trail mixes, cereal bars and cookies.
Coatings also provide a vehicle for delivering nutritional claims. Their high-fat matrix protects probiotics against the damaging effects of moisture and oxygen and helps maintain their vitality as they pass through the digestive tract, according to Laura Bergan, marketing manager, Barry Callebaut, Chicago, IL. The company conducted extensive research to develop its Probenefit chocolate line, which includes a no-sugar-added dark chocolate product sweetened with stevia.
Some limitations occur. “To protect the efficacy of the probiotics, Probenefit chocolate must be added at the post-bake stage to ensure that it is not heated over 107°F,” Ms. Bergan cautioned. The stevia-sweetened chocolate comes in an easy-melt form enabling ease of use for bottoming, enrobing or drizzling. Chips and chunks are also available.
“Time and temperature stability remains a key consideration,” Ms. Austin advised. Thus, addition of a probiotic enhancement should take place right before use in the final form or application and at the lowest temperature possible. “And a full shelf-life analysis is recommended in the finished product application with packaging under typical distribution and storage conditions to determine efficacy based on the nutritional claim being made."