How to Kill E. coli on Produce

Preparing produce properly can kill or remove E. coli and other pathogens.

Fresh produce may harbor a range of pathogens, but E. coli (short for Escherichia coli) is among the worst for its potential to cause illness if even small amounts are ingested. The danger is especially great for children, the aged or those with weakened immune systems. A process that irradiates produce and other edibles to kill pathogens including E. coli is not generally used for produce and, in any case, is not available to the home gardener. But taking proper steps to wash and prepare produce can help you avoid illness.

Things You'll Need

• Clean water
• Vegetable brush
• Peeler
• Colander
• Vinegar, chlorine bleach or produce sanitizer

Instructions

1. Wash your hands thoroughly with soap and water before handling produce. Ensure that salad bowls, cutting boards, countertops, knives and other food preparation areas and utensils are washed thoroughly with soap and clean water (or a mild solution of the chlorine bleach/water mix noted below) to avoid the potential of cross-contamination of E. coli from meat, other produce or dirt picked up from your surroundings.

2. Wash the produce. Use clean running water to remove surface dirt and use a vegetable brush will help remove particles. For such produce as lettuce and cabbage, remove the outer leaves and, if the leaves are open (such as is common in spinach), separate them.

3. Use a vegetable brush or peel. Brush produce with skin you will leave on. Or peel vegetables as needed such as carrots, white potatoes, sweet potatoes and oranges. After peeling, wash the produce as you would unpeeled produce.

4. Soak the produce in a sanitizing solution. Place the produce in a sink or bowl and use one of the following methods: a) Prepare a blend of about 1 1/2 tsp. of 5.25 percent sodium hypochlorite bleach such as Clorox per gallon of water and soak for 20 minutes, then rinse with potable water. b) Soak in white distilled vinegar before rinsing. c) Soak in a commercial product designed specifically to kill pathogens; brands include such products as Bacdyn, Microdyn and CitroBio (a citrus seed extract product). Note, however, that you should use a product specifically designed for food use.

5. Rinse and drain the produce. After soaking the food in a bleach solution or other antibacterial product, rinse your produce thoroughly in clean water. Drain well.

6. Optional: Pasteurize or cook your food. E. coli is killed through pasteurization or heating to a minimum of 160 degrees Fahrenheit. However, since most vegetables and fruits are eaten raw or prepared with other foods, they are often not heated to these temperatures so it will be necessary to clean them as above.

Tips & Warnings

• To avoid contamination of other foods or refrigerator shelves, it's best to disinfect produce (or wrap it very well) prior to storing it at home or placing it in the refrigerator. If you do wash and disinfect the produce when you first bring it home, but do not intend to use immediately, then let it dry thoroughly to avoid mildew and ensure it lasts as long as possible.

• Remember to rinse your produce after using an antibacterial agent or chlorine mixture. Do not use normal soaps or hand sanitizers, even those called "antibacterial" for cleaning produce since they can contain ingredients that are unsafe to ingest. Also note that some products that are called fruit or vegetable washes may simply "wash" the produce. Read the label to ensure it will kill E. coli and other pathogens. Always follow the use instructions for the specific product.

References

• Science Daily; Dr. Mom Was Right -- And Wrong -- About Washing Fruits And Vegetables; Apr. 16, 2008
• Colorado State University Extension; Preventing E. coli From Garden to Plate; J.G. Davis and P. Kendall; April 2005
• WNCNews: Five Ways to Avoid E. coli Bacteria
• Cooking in Mexico: How to Clean and Disinfect Fruits and Vegetables in Mexico