Almost all households consume packaged or bagged salads. We are accustomed to thinking that the food we purchase is safe – but how safe?
Prepackaged vs non-packaged greens – Some say bagged greens may be more at risk of containing bacteria than a regular head of lettuce because the leaves are younger and cut. Bacteria can enter the cut and travel into the leaf whereas a head of lettuce has longer leaves and the consumer can remove the outer leaves. In addition the many steps to get a bagged lettuce to market means many more opportunities for contamination. Also inside the bag the growth of bacteria can continue. *
Some say that bagged leafy greens are the riskiest food one can eat in terms of food safety. A lettuce leaf and other greens have crevices and raised areas where soil, chemicals and bacteria can “hide”
Many packages contain “pre-washed” greens and sometimes “triple washed”, but they can still contain harmful disease-causing bacteria, like Listeria, salmonella or E. coli, which can not always be rinsed off. Pesticides and other chemicals are on regular & pre-packaged foods. However they say not to be alarmed, because the product will be washed with chlorinated water – often greater than the concentration in a swimming pool. But because of the nooks and crannies, even in “triple-washed” leaves, some adhered bacteria may remain attached to the leaf and continue to live and grow. The leaf surface forms a microenvironment that reduces the bleach concentration and allows bacteria to grow. **
Triple Washed – greens aren’t necessarily washed with water. In fact they are usually washed with sanitizers and other compounds that are intended to reduce pathogens which eliminates about 90 – 99% of the microbes. However that 1-10 % may remain and grow.***
When one hand washes greens at home, one examines every leaf, but commercial machines are not so careful and some dirt and grit gets through. A lettuce cleaning solution for the masses is used – chemical additives, not potentially harmful like pesticides- and not to be feared. They are used to improve the industrial process and clean the vegetable. The salad mixes do not simply go through a sprinkler three times and then to the drying machines and then popped into a plastic bag, but rather go through chemical solutions containing chlorine and ozone which are added to the water to make an effective cleaning solution. Large packaging firms develop their own cleaning mixtures and label them on their package. Complaints about pre-washed bagged salads often refer to the gritty texture, the slimy texture or the flavor is a bit off. Lettuce is filled with nooks and crannies and not the easiest vegetable to wash. The sand and grit just gets in there and does not let go and can have a gritty texture. These chemical washes, although generally recognized as safe by the FDA, can create the “off” flavor that some persons object to in packaged salad mixes. Also this “off” flavor can be due to the fact that the product after being washed and pre-cut and placed in a plastic bag for a week or two before you bring it home. The slime – that is “rot” and rotting vegetables harbor bacteria. Lettuce that has been washed, cut and packaged, tends to spoil more quickly. Sometimes preservatives are used to maintain freshness and the bags may be punched with special holes that allow it to respire or breathe. Also some claim that the nutritive value begins to decline immediately after harvest and continues as the product is cut up, washed and put into a bag. ****
If you want the convenience of pre-washed lettuce and salad mixes, there are some things you can do at home. – WASH THE LETTUCE. WASH THE SALAD MIXES. Wash away any grit, wash away the slimy lettuce, and wash away at least some of the bacteria. Wash the product before you eat it, whether or not it has already been washed. Wash only the amount you will eat at the time. When washing lettuce take care to not add additional contamination. Do not mix with utensils, cutting boards, bowls, etc., that have been used to prepare other foods. Do not put lettuce or salad greens directly into the sink as sinks may hold bacteria and you can cross contaminate.
Also watch the expiration dates on prepackaged products and always store products in the refrigerator.
KEEP EATING THOSE VEGETABLES, EAT THE LETTUCE AND EAT THE SALAD GREENS – JUST WASH THEM AND THEN ENJOY!
You may also like to read – in this blog:
Food Safety in Produce, www.foodcrumbs.com, 6/29/2014
Vacuum Cooling of Produce, www.foodcrumbs.com, 11/28/20012
Lettuce-Harvesting, Storage, & Transport, www.foodcrumbs.com, 10/31/2012
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- Sadler, Alex Thomas, The Potential Health Risks of Bagged and Prepackaged Lettuce, http://clark.com-health-care, January 19, 2017.
** Breyer, Melissa, 7 Reasons to Ditch Packaged Salads, http://www.treehuugger.com/green-food, August 20, 2015.
*** Kearse, Stephen, Why are Salad Greens Always Labeled “Triple-Washed”?, www.State.com, April 27, 2016.
**** Sidhu, Allison, Pre-Packaged Salad Mixes: Are they Really Safe?, http://foodal.com/knowledge/paleo/safety-of-prepackaged-salad-mixes/, November 24, 2015