Guest Editorial
Support your local flora

Joseph O’Donnell is executive director of the California Dairy Research Foundation. He contributes this column exclusively for Cheese Market News®.

Support your local flora. I am not talking flowers here but something at the gut level. We all come into this world pretty much sterile as far as bacteria microflora go. But starting with our birth, our mothers inoculate us and the process continues throughout life.

As you know, we live in a microbially-dominated world protected by our skin and whatever defense mechanisms nature has bestowed on us in order to hold our own position on this planet. In the spirit of going along to get along, we will host 10 times as many bacterial cells in and on our bodies than we have cells of our own DNA. It’s quite a system. It seems like nature recognized that it is a tough world out there and that our immune systems, as good as they are, simply couldn’t carry the weight or resistance all by themselves. So nature took the organic route — increasing the heterogeneity of friendly bacteria associated with our bodies so that we could compete against those bacteria with vile intentions.

Bacteria enter our bodies wherever they can get past the skin. That means cuts or the various openings in our bodies, most notably the mouth. Foodborne infections remain part and parcel to any organism that has a mouth. This threat starts at day one of our entry into the world. The gut is set up to be fertile ground for bacteria — it needs bacteria. So, right off the bat mom gives us a mixed inoculum of bacteria that were enjoying life in her environment. But that’s not the whole of it. So now the infant gut is going to see this mixed bag of bugs looking for a home and not all these bugs are well-intentioned; some are downright nasty or even deadly. How is the gut going to sort through all this and survive? As you might have guessed, let’s look at the primary product going into the infant’s mouth — milk.

Scientists around the world know that oligosaccharides are not digestible to humans, yet they do support the growth of bacteria, the probiotic bacteria as well as other bacteria. Commercially, oligosaccharides based on fructose (FOS) dominate as additives in dairy products marketed as carrying probiotics. FOS is cheap and available from plants. However, another classification of oligosaccharide is the galacto-oligosaccharide (GOS). These non-digestible galactose-based carbohydrates are found in milk, and they too support the growth of probiotics. Why in the world would nature invest energy and material putting GOS in milk when it is not even digestible? It could be that nature uses very specific GOS to encourage growth of very specific probiotic bacteria in the infant to build a defense system as well as untold other advantages.

It makes a lot of sense ­— so much so that many university researchers have turned their efforts to supporting this concept. One of the leading researchers behind this concept is Professor Bruce German at University of California at Davis. Since he came up with this hypothesis, the analytical technology to isolate the GOS from milk and then measure the amounts of the various GOS compounds were developed and placed in the UC Davis laboratory of Carlito Lebrilla. With the GOS separated and identified, they could be fed by UC Davis’s Dave Mills to a wide selection of bacteria isolated from infant and adult human sources to see which bug does best with which GOS. If the bugs that do best with the GOS are also the ones with the greatest probiotic potential, imagine the ramifications to product development and nutritional messages around milk.

Today’s market finds pills containing probiotic bacteria or dairy products containing probiotics and supplemented with plant-derived FOS. Tomorrow’s market will find these probiotics contained in a delivery system designed to maximize the probiotic contribution and those systems will be milk-based. This entire concept has captured the imagination of scientists around the world and now represents a very competitive arena, with each scientist trying to be the first to uncover a new facet of the milk/probiotic relationship.

As the researchers move forward, clinical studies will emerge, more bacterial isolates will be fully characterized and scientific knowledge will explode. All of it will be focused on understanding the role that these relatives of lactose play in promoting probiotic activity. Animal geneticists then will jump in to find those cows that produce the most GOS and then select accordingly to maximize this value-added component. At this juncture, the efforts of the International Milk Genomics Consortium (www.imgconsortium.org) will come into play with milk producers around the world accessing the database and moving to capture this market for value-added milk.

In relatively short order, the universities will have culture collections of important probiotic bacteria whose performance correlates to the presence of milk components. Researchers around the world will have access to these bugs and will continue to work out the metabolic relationships between the bacteria and dairy products. Manufacturers either can find their own strain selected by following the published academic process or simply license strains known to deliver benefits when in the presence of dairy products. Whatever the process, the dairy industry produces and sells the product needed by the probiotic bacteria, and the consumer benefits.

CMN

The views expressed by CMN’s guest columnists are their own opinions and do not necessarily reflect those of Cheese Market News®.