Skip to content

Most Bacteria In Kitchens Are Harmless

Ever wonder what bacteria are living on your kitchen surfaces, including sponges? It turns out that even with different hygiene, dietary habits, and cooking practices, there is a core group of bacteria that are common to all kitchen surfaces (core microbiota). At least this was true for residential kitchens in 5 European countries.

The Norwegian researchers took samples from 74 kitchens in 5 countries - France, Norway, Portugal, Romania, and Hungary. Bacteria were sampled from cutting boards, counter tops, sinks, handles, and cleaning utensils, including sponges.

The researchers found that the core microbiota in European kitchens were of eight genera or families.  They are: Acinetobacter, Pseudomonas, EnhydrobacterEnterobacteriaceaePsychrobacterChryseobacteriumBacillus, and Staphylococcus.

The researchers mention that other studies also found Acinetobacter (part of the core bacteria) in all kitchen samples in all countries (including USA, South Korea), and in high abundance. It probably enters kitchens daily because it is on vegetables, meat, fish, milk, and even in drinking water systems. By the way, these bacteria are not a threat to humans!

Bottom line: Bacteria are all around us, including in our kitchen - and that's OK. Most are harmless! However, harmful bacteria such as Salmonella can enter kitchens through contaminated food.

From Science Daily: Bacteria in kitchen may not be as harmful as you think

Bacteria found in 74 kitchens spread among 5 European countries were mostly harmless according to new research published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology.

"We have previously found considerable variations in kitchen standards, food preparation practices, and cleaning regimes between France, Norway, Portugal, Romania, and Hungary," said Birgitte Moen, Ph.D., Scientist -- Department of Food Safety and Quality, Nofima -- Norwegian Institute of Food, Fisheries, and Aquaculture Research, Ås, Norway.

In the study, the researchers sampled bacteria populations from sinks, cutting boards, counter tops, handles and cleaning utensils -- sponges and cloths -- used in kitchens.

Despite large numbers of species and considerable differences in bacterial diversity between samples, the researchers identified 8 bacterial genera commonly associated with environmental sources in most of the kitchens they sampled, which they characterized as "core microbiota." These included Acinetobacter, Pseudomonas, Enhydrobacter, Enterobacteriaceae, Psychrobacter, Chryseobacterium, Bacillus and Staphylococcus.

In the report, the authors stressed that the core microbiota persisted despite considerable differences between kitchens in the study. Some kitchens lacked running water, some lacked an indoor sink and some lacked dishwashers. They also persisted despite differing food preparation methods, dietary habits and differences in hand and kitchen hygiene, both of which affect the probability of infection.

The study was motivated by the authors' curiosity, said Moen. Bacteria in food, in the gut, in hospitals and in professional food production had been well researched, but little was known about the microbes that inhabit the domestic kitchen. With an already existing collaboration across countries, "we had a unique opportunity to dig into this," Moen added.

The team knew that harmful bacteria enter kitchens via contaminated food, and that the type of these bacteria varied across countries. For example, Salmonella is not a problem in Norway, but it is the most commonly reported cause of foodborne illness in mainland Europe. Knowledge of the bacteria inhabiting the domestic kitchen could be used to help prevent human illness, and perhaps could even lead to more hygienic kitchen designs and better cleaning utensils, said Moen.

Leave a Reply

Your email address will not be published. Required fields are marked *