Delivering probiotics, part 3
by Laurie Gorton
Yes, baked foods can effectively deliver probiotics, provided certain conditions exist. Kayla Polzin, PhD, principal probiotics scientist, Cargill, Wayzata, MN, describes consumer health benefits and bakery processing conditions in this exclusive Baking & Snack Q&A. There’s plenty of market potential for these ingredients because 38% of Americans now “manage” a digestive problem.
Baking & Snack: How do probiotic ingredients foster better digestive health in humans? Can you share recent research that supports this capability or describes mechanism for this activity?
Kayla Polzin: Every human being contains within their gastrointestinal tract trillions of bacteria that are critical to our survival. In fact, if you counted all the cells in a human being we would be 10% human and 90% bacterial (if you go by DNA, we’re 1% human and 99% bacterial). These bacteria help us to extract nutrients and energy from food, moderate the activity of our digestive tract, train and help control our immune system, fight off pathogens, and may even communicate with our brains in ways that can affect mood and feelings of digestive comfort. Different bacteria can have different effects, and by consuming these bacteria we can modulate some or all of these activities that occur in our GI tracts.
A recent paper from Jeff Gordon’s lab published in Science Translational Medicine showed how probiotics can act by impacting the gene expression of other bacteria in the GI tract (McNulty et al. 2011. Sci. Translational Medicine 3:106). Another paper from Michael Kleerebezem’s laboratory reported how probiotics affect gene expression in human intestinal cells (Baarlen et al. 2010. PNAS 108:4562). A short review can be found at Shanahan (2010) Gastroenterology 139:1808.
What do formulators need to know about the way these ingredients perform during preparation and processing? Are there limits — regulatory and/or practical — on usage levels in formulations?
There are a number of factors that affect the use of probiotics in foods. Many (but not all) organisms used as probiotics have been consumed as parts of fermented dairy products for millennia and have proven safe to consume at levels of 10 billion cells per day and probably higher. The limiting factors in adding probiotics to food are primarily about keeping the bacteria alive.
Probiotics are defined as “LIVING microorganisms which, when consumed in adequate doses, provide a health benefit to the host.” The key word is “LIVING.” Most manufacturing processes and food formulas are designed to inhibit and kill bacteria. Or their shelf life is such that adequate numbers of bacteria can’t be kept alive to the end of shelf life.
Also, it’s essential to consume the probiotic bacteria regularly because they don’t (generally) colonize your GI tract and will disappear from your system within a matter of weeks if not regularly replenished. Ideally, probiotics should be consumed every day, which means that the food they’re incorporated into should be something that consumers can be expected to consume daily without any adverse effect on health.
Are your ingredients better in some applications than others? What types of baked foods and snacks make the best use of these materials?
Probiotics are best supplied in short shelf life refrigerated foods. However, recent advances in encapsulation have extended the shelf life in nonrefrigerated foods. For baked foods and snacks, the best applications have low water activities and shelf lives of less than six months. The probiotic would also need to be added after baking or extrusion.
What ingredients does Cargill offer that help create such applications in the baked foods and snacks categories?
According to a recent report on probiotics, 38% of US consumers are currently managing a digestive problem. At Cargill, we are continuously exploring new and innovative solutions to help our customers formulate around the growing consumer demand for food products with digestive health benefits. 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. Following are Cargill’s current products in the probiotics space:
* VIABLE Cultures
These are single strains or combinations of probiotic cultures of Bifidobacterium lactis, Lactobacillus johnsonii (formerly Lactobacillus acidophilus), Lactobacillus paracasei and Lactobacillus rhamnosus. These concentrated, frozen cultures are optimized for high counts throughout product shelf life and for the best potential to contribute to intestinal health.
* SBIFIDUS BATL Cultures
This range of probiotic yogurt cultures consists of the acidifying strains Streptococcus thermophilus and Lactobacillus delbrueckii subsp.bulgaricus plus two, three or four different probiotic strains of the probiotic strain options listed above in the VIABLE section. Selecting from the range of BATL cultures allows production of mild yogurt with varying flavor and texture profiles.