Salmonella and E-Coli Can Thrive In Fruits and Veggies

Salmonella and E. Coli Can Thrive Inside Tissues Of Fruit & Vegetables











Sanitizing the outside of produce may not be enough to remove harmful food pathogens, according to a Purdue University study that demonstrated that Salmonella and E. coli can live inside plant tissues.

E. coli 0157:H7 was present in tissues of mung bean sprouts and Salmonella in peanut seedlings after the plants' seeds
were contaminated with the pathogens prior to planting.

Food science researchers said seeds could be contaminated in such a manner before or after planting through tainted soil
or water.

"The pathogens were in every major tissue, including the tissue that transports nutrients in plants," said researchers, whose results were published in separate papers in the Journal of Food Protection and Food Research International.

Researchers specializing in botany and plant pathology, said finding pathogens inside plants has been challenging because tests require slicing off pieces of the plants, which can move the bacteria from the outside to the inside or vice versa. It becomes difficult to know where a pathogen might have been before the plant was cut.

"The results are often imprecise because the methods allow bacteria to move," they said

In a new study, researchers used a fixative to freeze the location of the bacteria in the plant tissues before slicing samples. Antibodies labeled with fluorescent dye were used to detect the pathogens, a process called immunocytochemistry.

"This shows us as close to what was in the plant when it was living as possible; The number of bacteria increased and persisted at a high level for at least 12 days, the length of the studies." able to count hundreds of bacteria in almost every type of tissue, they explained.

Proper sanitization would eliminate Salmonella and E. coli
from the surface of foods, but not inner tissues, Cooking
those foods to temperatures known to kill the pathogens
would eliminate them from inner tissues.

Researchers continue to study the pathogens to determine how they survive inside plant tissues and possible ways to eliminate them. The U.S. Department of Agriculture's Agricultural Research Service funded their work.

Story Source: Purdue University.
Journal References:

"Identification of the Cellular Location of Internalized Escherichia coli O157:H7 in Mung Bean, Vigna radiata,
by Immunocytochemical Techniques" Journal of Food Protection, 2011;

"Internalization of E. coli O157:H7 and Salmonella spp. in plants: A review." Food Research International, 2011

This article is for informational and educational purposes only, and is not intended to provide medical advice, diagnosis or treatment. Consult with your doctor or healthcare professional for medical and nutrition advice.