Purchasing pre-bagged leafy green salads is a convenient way for many people to eat more healthy vegetables. When buying unpackaged leafy greens or any other fruits or vegetables, it is very important for consumers to wash them (under clear running water) once at home to clean off any bad microorganisms that may be present. However, if you are buying pre-bagged leafy green salads, it is important to read the label to see if it has already been washed. If it is labeled “washed” or “ready-to-eat,” then you do NOT need to wash it at home.
Washing pre-washed leafy greens has not been shown to reduce the risk of foodborne illness, and actually may increase the risk of cross-contamination in your kitchen. The commercial washing process removes 90-99 percent of all microorganisms that may be present, so it will be difficult for any washing at home to remove much more. Also, when washing the greens, any microorganisms that may already be present in your sink, your countertops or on your hands could easily contaminate the greens even more.
The most important things consumers can do to prevent foodborne illness from eating pre-washed bagged salads is to keep them refrigerated at 35 to 40° F, observe the “use by” dates marked on the package, and don’t buy any salad that has excess water in the bag or has not been kept refrigerated. As with any fresh fruits and vegetables, always handle pre-washed greens with clean hands, and make sure cutting boards, utensils and countertops are clean.
An article with more information on this topic, including food safety recommendations for consumers, is available here: http://foodsafetypundit.com/docs/fresh-cut-greens-handling.pdf
Read more at http://missourifamilies.org/features/foodsafetyarticles/fdsfty63.htm
Contributor: Londa Nwadike, PhD, Extension Food Safety Specialist, University of Missouri Extension,