Bagged Salad Is a Breeding Ground for This Deadly Bacteria

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If you plan to serve or eat bagged salad over the holidays, you might you want to reconsider those plans.

New research shows bagged salad is uniquely suited for breeding salmonella, the bacteria responsible for the food-borne illness salmonellosis.

Researchers at the University of Leicester in England found that over a typical five-day period of refrigeration, around 100 salmonella bacteria multiplied to approximately 100,000 individual bacteria.

Their findings were recently published in the journal Applied and Environmental Microbiology.

At the root of the problem is the “juice” found in bagged salad. This juice comes from the lettuce leaves themselves when they are damaged, and it mixes with any water present inside the bag.

The study found that when the juice was mixed with water, it more than doubled the movement of individual salmonella bacteria.

Researcher Giannis Koukkidis, a graduate student, explains:

“This salad juice can stimulate salmonella growth massively in this salad plastic bag environment. Salmonella also attaches more aggressively to the salad plastic bag when it comes in contact with salad juices, and salmonella can even grow in the fridge much faster when it comes into contact with salad juices.”

Normal microbes present on the salad leaves did not respond to the juice, however. That led the researchers to believe that the juice gives salmonella “a marked advantage” over other bacteria attempting to multiply on the lettuce, according to the study.

Salmonella causes an estimated 1 million illnesses in the U.S. each year, including 19,000 cases that lead to hospitalizations and 380 that end in death, according to federal government data. That’s more than any other bacteria associated with food poisoning, including the notorious E. coli.

To learn more about how to protect yourself from salmonella, check out “7 Keys to Dodging Deadly Bacteria Lurking in Your Food.”

Does this news change your mind about bagged salad? Let us know below or on Facebook.

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