[Frozen/Refrigerated Foods] Vol. 20 No. 8 August 2010 ww Deliciously Frozen Probiotics—Ice Cream and Beyond By Cindy Hazen, Contributing Editor Given a choice between cultured buttermilk or a bowl of ice cream, most Americans would choose the latter. Buttermilk may be a healthier option, because it feeds us friendly bacteria that fortify our digestive system, but ice cream is infinitely more satisfying—even if we perceive it to offer us mostly flavor and calories. Adding probiotic bacteria to ice cream and frozen desserts Sweet Sales removes potential guilt and gives us reason to enjoy our The U.S. ice cream and frozen-dessert favorite scoop. But for the manufacturer, adding these market reached $24.6 billion in 2009, microscopic organisms requires a little know-how. notes a Jan. 2010 report published by Packaged Facts, “Ice Cream and Probiotics: It’s alive Frozen Desserts in the U.S.: Markets and Opportunities in Retail and Foodservice, 6th edition." Sales are National Yogurt Association, McLean, VA, notes that projected to reach $26.5 billion by probiotics are living microorganisms, which upon ingestion 2014. Frozen yogurt represents an 8% in sufficient number, exert health benefits beyond basic share of U.S. frozen-dessert sales. Ice nutrition. “Probiotics need to be viable in order to have any cream, on the other hand, comprises nutritional value, and thus must be incorporated post- 59% of sales. Frozen novelties make up 30% of sales. Further, the report pasteurization," says Peggy Pellichero, senior food notes, “the trend has taken a turn in technologist—dairy team leader, David Michael & Co., that it now focuses primarily on Philadelphia. “Interestingly enough, the freezing process products that have added ingredients, does not kill the organisms, it just puts them into a dormant like probiotics and omega-3, that state until consumed." promote good health, rather than products that have eliminated ingredients." While the probiotics must be added after pasteurization so they won’t be killed by high temperature, there isn’t consensus as to which step they should be incorporated. “We generally recommend that they be added at the flavor vat," says Jon Hopkinson, Ph.D., senior applications scientist—frozen desserts, Danisco USA, New Century, KS. “Flavoring should not be added at exactly the same time, as concentrated flavors can damage the probiotic cell. Further, it would be good practice to avoid excessive mixing or air incorporation into the mix." Shear and oxygen exposure during manufacture can impact the survivability of probiotic organisms. According to Mike Bush, vice president of business development, Ganeden Biotech, Inc., Mayfield Heights, OH, the most important part of the formulation process is finding the best possible way to add the probiotic within the manufacturing process where the highest amount of cell survival can be demonstrated. “Because probiotic organisms can be extremely fragile, they need to be protected from extremes ranging from temperature and pH to pressure and rapid environmental shifts," says Bush. “One of the www.foodproductdesign.com Page 1 [Frozen/Refrigerated Foods] Vol. 20 No. 8 August 2010 issues in manufacturing frozen products is the shift in temperature from cold to frozen. Many times, there are large losses when temperature shifts from the mixing temperature to freezing temperatures, and such shifts make many such applications cost-prohibitive." Probiotics generally survive well in ice cream and frozen desserts, but care is needed. “Anything that can affect the formation of ice crystals in ice cream can affect the bacteria," cautions Hopkinson. “Slow hardening and heat-shock cycles can, therefore, affect the viability of the probiotics. In resale mixes that are frozen for distribution, it is very important that the freezing process be as fast as possible for the same reason." The pH of the frozen dessert is important. “It would seem counterintuitive in light of recent frozen yogurt popularity, but very low pH product should be avoided," Hopkinson continues. Bush notes that, since traditional probiotics tend to be more fragile than spore-forming strains, sometimes they require an extra step or change to the manufacturing process to increase viability. “The spore-forming probiotics do not require this," he says. Spore-forming probiotics are hardier than other probiotics. “The use of such spore-forming organisms eliminates many of the inherent limitations found with non-spore-forming organisms and make difficult applications possible," Bush says. “For example, in frozen applications, the Bacillus coagulans spores simply remain dormant and are very stable through the end of the shelf life of the finished product." The company offers a strain of B. coagulans that is a spore-forming bacterium, meaning it builds a hardened structure inside the cell that protects the cell’s genetic material from extreme temperatures, pressure and low pH. Lactic acid bacteria are among the hardiest of the non-spore-formers, because they naturally produce a protective layer of exo-polysaccharides. However, these secretions don’t completely envelop the bacteria, so they are only partially shielded. Federal regulations do not dictate which organisms should be used in frozen desserts, or even their viability. There isn’t even a standard for frozen yogurt. According to the National Yogurt Association, some products that are called frozen yogurt use heat-treated yogurt in which all of the cultures have been killed, or the cultures have been added but the fermentation step has been missed. If these bacteria do not survive processing, or don’t survive the digestive process to confer a benefit to the host, they do not meet the definition of probiotics. Every probiotic strain possesses unique characteristics, and the amount of probiotic added to a product depends upon the supporting clinical data on the strain. “Probiotics need to have the clinical support to demonstrate a proven health benefit, and health benefits are strain-specific," says Bush, noting that the company’s B. coagulans, provides benefits to consumers at 500 million to 2 billion colony-forming units (CFU) per serving. Label declarations are dependent on the strain. “Content claims are the most common," notes Hopkinson. “Structure/function claims require close control of the number of probiotic bacteria in the product through shelf life, and the manufacturer will need to be able to support the claim with the www.foodproductdesign.com Page 2 [Frozen/Refrigerated Foods] Vol. 20 No. 8 August 2010 research that supports it. The actual number of probiotic bacteria per serving is dependent on the amount used in the research. Probiotic suppliers should provide this research." Ultimately, for any product carrying a probiotic declaration, it’s the manufacturer’s responsibility to test the finished product to be certain that the minimum viable numbers of each probiotic strain survive to the end of shelf life. Optimal probiotic formulation Typically, there is no need to use specialized stabilizer systems when formulating an ice cream or frozen yogurt that contains probiotics. “Any system that provides an excellent texture and stability is appropriate for probiotic ice cream," says Hopkinson. That said, success of the stabilizing system is more critical to probiotic-rich frozen desserts. A good stabilizer will reduce ice-crystal size and minimize weeping. If unchecked, syneresis can lead to the development of large crystals. Controlling the formation of ice crystals will give the product a creamier texture, but the ultimate benefit in these products is greater probiotic survivability. Using a probiotic-cultured base mix, “seems to add creaminess and body to an otherwise weak and low-fat frozen-dessert base mix," says Pellichero. “The probiotics need to be cultured in a dairy base mix in order for them to propagate. This culturing process creates a mix that is viscous and, thus, adds the body and texture to the finished product." Her company developed a frozen dessert that used kefir as a source of probiotics. She suggests flavoring these types of products with superfruits such as yumberry and goji berry, “because the tartness of the base mix complements the acidity coming from the superfruit." Hopkinson recommends avoiding mixes with low solids, and those that are high in monosaccharides like fructose and glucose. These lower-molecular-weight carbohydrates may compete for water in the system and interfere with the functionality of the stabilizers. He suggests that formulations that are higher in maltodextrin, corn syrup or polydextrose can help with probiotic survival. These higher-molecular-weight carbohydrates can increase viscosity, especially when combined with high levels of milk proteins. An end-benefit is decreased, and more- effective, use of hydrocolloids. Polydextrose is beneficial to probiotic formulations because it is a prebiotic fiber that is only partially hydrolyzed in the small intestine. Technically, it is an oligosaccharide, a short chain of sugar molecules. In the gut, it is broken down to low-molecular-weight polydextrose polymers, which feed probiotic bacteria. In addition to oligosaccharides, milk protein and lactose—inherent in frozen yogurt, ice cream and many frozen desserts—provide a substrate for growth of probiotic organisms. www.foodproductdesign.com Page 3 [Frozen/Refrigerated Foods] Vol. 20 No. 8 August 2010 Branching out Frozen yogurt, hard-packed ice cream and soft serve are all worthy applications for probiotics. But while consumer awareness of probiotics is on the rise, Bush believes that consumers may still associate probiotics with yogurt. “We believe that ice cream and frozen dairy deserts are fantastic delivery systems for quality probiotics," says Bush. “Consumers are looking for probiotic options and are looking for simple ways to incorporate probiotics into their everyday life without adding new foods and/or habits. Frozen dairy deserts and ice cream allow consumers the option of adding probiotics in a format that they already enjoy—and now can enjoy daily while feeling less guilt." Hopkinson adds that “ice cream is not anywhere near as bad a product health-wise as it is portrayed in the popular press.