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Understanding Microbes to Improve Food Safety

What can harm us can also help us


Probiotics have grown in popularity as an area of focus in our diets, from products like yogurt and sauerkraut to kimchi and kombucha, we have learned that the inclusion of probiotics can support a healthy gut. More and more research is also shedding light on how the role of the gut may be greater in our lives than we previously understood, with some calling the gut a “second brain” that significantly affects our moods and thoughts. The microbiome in our gut flora consists of trillions of microorganisms, the entirety of which science does not yet completely understand. Yet what is becoming increasingly clear is that a further understanding of this microbiome may lead to breakthroughs in science, not only in the health sector, but in cleaning and hygiene and food safety as well.


There is more research available now than ever before that explains that our current cleaning methods may leave something to be desired in cleaning potential due to a lack of knowledge around what microbes are, how they work, and what their affect is on human health.


There is more research available now than ever before that explains that our current cleaning methods may leave something to be desired in cleaning potential due to a lack of knowledge around what microbes are, how they work, and what their affect is on human health. As that knowledge grows, we will become more and more able to answer questions around how to manage microbes, and even work with them in order to improve human health through methods that extend beyond dietary needs.


Cindy Davis of National Institutes of Health explained at the symposium on Microbiomes in Food Safety, Food Quality, and Human Health that “Humans are composites of species, with up to ten times as many microbial cells as human cells. Our microbiomes benefit us in many ways: they allow us to harvest nutrients and extract otherwise inaccessible energy; produce vitamins; metabolize carcinogens; and compete with pathogens. Every individual’s microbiomes (which differ depending on body location) are unique to them.” What becomes clear then is the extent to which we are made up of organisms that are immense in scope and difficult to understand in their entirety, as each individual’s microbiomes are different from one another, creating unique questions regarding the optimal health and balance of each body.


Davis explains further, “Having a greater diversity of species seems to be important (and can help reduce susceptibility to pathogens), but it remains unknown exactly which organisms and what abundance of them is desirable for health. Although certain shifts in the human microbiome (gut and other locations) have been correlated with various states of disease, no definition for a healthy microbiome currently exists, and we cannot yet predict how broad changes to the microbiome translate into health effects.”


Yet, we have known for a long time that the manipulation of microbes can help to manage the spoilage of food; however, historically, we did not have the specific knowledge of what microbes are and how they work. The fermentation process, which is caused by the activity of specific microbes present in or added to a food or beverage, has existed, especially in beverages, since Neolithic times (about 12,000 years ago at the end of the Stone Age). We have used the fermentation process in our creation of beer, bread, cheese, vinegar, wine, and yogurt in Western culture for thousands of years, with many other common food products using fermentation processes in cultures beyond the West as well. Yet it wasn’t until the 19th century that we began to understand what fermentation was, with Louis Pasteur making the discovery that lactic acid fermentation is caused by living organisms in 1857.


Today, we still have much more to learn, but it is clear that microbes play a huge role in human health, beyond just our diet. Microbes exist on surfaces to a degree that we still do not entirely understand, although there is more research that shows that some cleaning methods do not yet entirely eliminate the buildup of biofilm, which is the collective of one or more types of microorganisms that grow on surfaces. Additionally, biofilm may not always be visible, which is why traditional cleaning methods may not always eliminate its presence. It is also difficult to determine the presence of biofilm on surfaces due to its potential lack of visibility, although, since biofilm is made up of bacteria, fungi and protists, it also has an effect on the existence and persistence of foodborne pathogens in food handling.


Research shows that the organisms that can harm us can also help us, if we are made aware of which ones we are working with and which ones we are eliminating.


So, it is clear that microbes exist on surfaces and have a potentially negative affect on our health, and that the presence of biofilm on surfaces, if not eliminated, can negatively affect every aspect of food handling. Yet, what is interesting to learn is that the use of microbes can also be the very thing to eliminate the hazards caused by other microbes and organisms, as further research into the subject has indicated. Research shows that the organisms that can harm us can also help us, if we are made aware of which ones we are working with and which ones we are eliminating.


For example, certain researchers have “investigated the fungal strain Trichoderma harzianum Th33 as biocontrol agent with [an] important role in disease prevention, improving the quality of agricultural products and reduction of pesticide hazards. Copper-tolerant Trichoderma can be used in combination with copper-containing pesticides and therefore reduce the use of chemical pesticides. In addition, it can also be used for bioremediation of copper-contaminated soils since copper pollution is disadvantageous to the quality and safety of food.”[1]



It may be surprising that the application of fungus into our food can in fact improve the quality of that food, rather than harm it. Some microbes when applied to food can even improve human health, such as Lactobacillus plantarum, which is a protective culture in cheese making. The work of researchers who are attempting to understand more about the interaction of microbes on food, specifically in the area of enhancing food safety and diminishing the spread of foodborne pathogens, are continuing to shed light on aspects of our own internal ecosystems that we would not be able to understand otherwise.


By Alana Hippensteele, Editor, American & Cleaning & Hygiene

[1] Nevijo Zdolec, José Manuel Lorenzo, and Ramesh Chandra Ray, “Use of Microbes for Improving Food Safety and Quality,” BioMed Research International, vol. 2018, Article ID 3902698, 2 pages, 2018.


Managing Slime


A biofilm on kitchen surfaces


Anyone in the foodservice industry knows slime when they see it, whether it’s inside the ice machine, on a cutting board, inside a floor drain or under a countertop-mounted piece of equipment.


What most people in foodservice don’t understand is that there is much more to slime than meets the eye. Unless foodservice professionals want to risk getting “slimed out of business,” they need to address slime as the menace it is and not just as a cleaning chore.


What we typically refer to as slime is actually biofilm, which is defined as a collection or community of bacterial cells. Often those bacteria are the bad variety, such as E. coli or salmonella, which can both cause foodborne illness.


In a foodservice environment, bacterial cells that have not been removed through proper cleaning and sanitizing procedures can stick to one another and to surfaces. Attempts to remove them sets off a reaction: They become stressed or threatened, then send out chemical signals to other bacteria in the area and generate a glue-like material (actually a complex sugar) that helps them stick together and launch a protective “shield” against the next attempt to kill and remove them. The longer this is allowed to continue the more difficult it is to correct.


Biofilm can develop on a variety of surfaces despite thorough cleaning and can easily spread. If biofilm is allowed to form on a cutting board, for example, the pathogenic bacteria will survive recommended normal cleaning and sanitizing processes. If a biofilm is present on a surface, and salmonella from a nearby food comes in contact with it, the biofilm will capture some of the salmonella bacteria. There it will not only survive but grow or reproduce within its new safe haven.


What Can Be Done?

As with many food-safety hazards, the best way to deal with biofilm is to prevent it from taking hold in the first place. If there is a hint of slime anywhere in the foodservice operation, don’t ignore it—attack it.



Sometimes our senses can also detect the start of biofilm formation. Visual signs may be a “rainbow” appearance on a stainless-steel surface, while tactile signs may be a slimy feel to a piece of equipment that normally feels clean to the touch. A sour or off smell doesn’t prove the presence of a biofilm, but it could be a warning sign; such a smell is generally a sign of improper cleaning, which could lead to biofilm formation.


As a biofilm is forming, it is still very vulnerable and can be removed with some extra effort. Once it has been allowed to develop, which may only be 24 to 48 hours, it moves into another stage that makes it much more difficult to eliminate. Biofilm can also establish itself more readily on rough or irregular surfaces, such as a pitted or chipped cutting board or a damaged food prep counter. This is just one more reason food codes specify that food contact surfaces must be smooth and easily cleaned.


If a foodservice operation gets slimed, management unfortunately only has their own cleaning methods to blame. There is no Ghostbusters team available to eliminate this slime dilemma.


By Steven Sklare, REHS/RS, CP-FS, LEHP, Everclean Strategic Business Development Executive