From Tank to Gut: Why You Need Microbiome Monitoring For Your Dairy Products
Since humans learned to farm and herd 11,000 years ago, milk has become a staple in every household. Since it is the source of proteins, essential amino acids, carbohydrates, fats, minerals, and vitamins, it's dubbed as a "complete food." Milk has impacted cultures and entire populations. In fact, it induced the emergence and persistence of the intestinal lactase enzyme in European populations, and eventually, the rest of the world.
However, not everyone can produce this enzyme to utilize milk products, especially adults. Thus, humans discovered the fermentation of milk into yogurt and cheese, a process that can make lactose digestible for people without lactase enzymes. But are we the only ones benefitting from milk products? Besides being nutritious to humans, milk can also be an excellent substrate for microorganisms.
Think about all the processes involved in milk production, from milking machines to storage. Many microorganisms might colonize your milk products, and pasteurization might not be enough to get rid of them. It begs the question: what species of microorganisms are present in your dairy products?
What microorganisms are present in milk?
Many believe that milk is free of any microorganisms, but recent studies prove that it's not the case. Bacterial colonization begins even before the milk is subjected to different industrial processes. Some of the bacteria found in milk are lactic acid bacteria like Lactobacillus and Enterococcus species, Gram-positive bacteria like Bacillus and Propionibacterium, and Gram-negative bacteria like Pseudomonas and Fusobacterium species. These microbes might come from the udder's skin or even the cows' intestines, carried by the immune and dendritic cells from the intestinal walls to the mammary gland.
As you already know, not all of these bacteria are beneficial. By understanding the microbial composition of your dairy products, your can improve the quality of your dairy products.
What causes milk spoilage?
If you think that low-temperature storage and pasteurization can get rid of spoilage bacteria, think again. These can decrease the proliferation of lactic acid bacteria, but other milk spoilage-causing bacteria may still persist in the product. For instance, Gram-negative bacteria that can degrade proteins and lipids in milk can cause low-temperature spoilage.
On the other hand, Gram-positive lactic acid bacteria can cause the good kind of spoilage — the kind that makes cheese and yogurts. This will improve the shelf-life and taste of your dairy products.
When is dairy bad for one's health?
The marketing and consumption of raw milk have increased in recent years, especially with the emergence of raw milk vending machines in farms. Raw milk might be dangerous to consumers' health as unpasteurized milk contains pathogens. These bacteria cause significant diseases like campylobacteriosis and listeriosis. The latter has a high hospitalization and fatality rate. They may also contain toxins like staphylococcal enterotoxin and aflatoxin M1.
How do you keep your milk and dairy products safe for your consumers?
At this point, you might think that if a higher diversity of gut microbiome is positively associated with gut health, consumption of bacteria-colonized raw milk can improve gut health as well, right? Well, it's not that simple. Without metagenomic analysis — that is, knowing the bacterial species present in your dairy products via the approximation of all genes present in it — you won't know whether the bacteria present in our dairy products are safe, beneficial, or pathogenic.
As producers, you are responsible for keeping your dairy products safe for consumers. Make sure to pasteurize your dairy products before declaring them safe for consumption. Pasteurization will rid your milk products of bacterial pathogens like Shiga toxin-producing E. coli (STEC) and Campylobacter. At the very least, remind your consumers to boil the milk if they prefer raw milk.
The solution to your dairy problems
Is boiling or pasteurization enough? As mentioned earlier, some bacteria and toxins can survive pasteurization and low-temperature storage. Further, the goal is not to eliminate all the microorganisms in your product but to monitor the microbiome present, whether they're beneficial or not, and get rid of the pathogenic ones. After all, the diversity of good bacteria in your milk products can improve your consumers' gut health.
To ensure the quality of your milk products, know the microbes' species and quantity present through microbiome monitoring. More traditional methods like culturing and biochemical tests may take too long and cost a lot. There's also the possibility of nondetection as some bacterial species are not culturable.
As such, you'll need molecular techniques to get more accurate and efficient results. Here at Eurofins, we use both classical and modern methods such as real-time PCR to determine and characterize the microbes up to the strain level. What's more, our services include Challenge tests and Shelf-life studies to ensure your products are at their best.
Contact your local Eurofins laboratory if you have any questions about microbiome monitoring.
