Quick facts
- Washing fresh produce with potable water treated with a sanitizing agent reduces illness-causing pathogens.
- To maintain appropriate levels of sanitizer in your wash water, use test strips or another method to verify the concentration after each addition of sanitizer.
- Always read and follow the sanitizer label instructions.
When washing your produce in a dump tank or other tank with recirculated water, it is recommended to use a sanitizer in the water to reduce the chances of spreading illness-causing pathogens, such as E. coli, Cyclospora and Salmonella. These organisms may be present in the soil or on the skin and rinds of fruits and vegetables, and wash water can spread that to other vegetables.
Sanitizers reduce the potential for cross-contamination by reducing the overall microbial load of the water, keeping it clean and fresh. Sanitizers can also increase the shelf life of some products such as greens, as the sanitizer will also kill organisms that can cause decay and rot.
- Use sanitizer in your wash water when rinsing leafy greens (lettuce, spinach), peppers, green beans, green onions, melons, cucumbers and zucchini.
- Do not wash berries (strawberries, blueberries, blackberries, raspberries) or tomatoes.
- Keep chlorine and other sanitizers away from children and pets and in tightly closed and labeled containers away from heat and direct sunlight.
- Read and follow label instructions; sanitizing chemicals can be toxic at full strength.
How to use sanitizer in your wash water
Step 1. Remove soil and organic matter from produce before washing
Organic matter, such as dirt and other debris, reacts with the sanitizer solution to lower its effective concentration. The more organic matter in a water and sanitizer solution, the less effective the sanitizer is.
Lightly brush produce with thick skins or rinds (melons, potatoes, carrots) or prewash leafy greens.
Step 2. Measure and mix the sanitizer in your wash water
The sanitizer you use must be labeled for use on fresh fruits and vegetables. For suggestions for choosing a sanitizer, see the bottom of this page.
Follow the directions carefully on the label of your product. You might have to seek out the complete label for the product online, using the EPA registration number of the product. The label will indicate the specific PPM, or concentration, of the product when being used for fruit and vegetable washing.
- Water used for washing must be clean and potable (drinkable).
- Water temperature should not be more than 10 degrees F cooler than the interior of the produce to reduce the potential for infiltration of the water into the produce. If the water is colder, the water and any pathogens in the water can be sucked inside and no amount of sanitizing will kill the interior pathogens.
- Water should be at a cool temperature, but not cold. If it is too cold the sanitizer will not be effective. If it is too warm it may encourage the growth of some pathogens and diseases. Generally, sanitizers work best between 55 degrees F and 120 degrees F. Check the label of the sanitizer for effective temperature range.
- Make sure to use proper protective equipment when handling the sanitizer, such as gloves, an apron and goggles.
Step 3. Rinse products in solution
- Gently submerge the produce in the water with the sanitizer.
- Very gently move the produce through the water.
- Let the water remove the dirt, not your hands.
- Do not immerse tomatoes. Tomatoes should be wiped with a clean cloth that has been dipped in sanitizer solution, or wiped with single-use paper towels.
- Make sure that you let the produce remain in the solution for as long as indicated on the label.
Step 4. Rinse products in fresh water if indicated by the label
Read the label carefully. Some sanitizers require a freshwater rinse, others do not.
Step 5. Change water frequently
Used wash water can be poured onto non-edible crops, grasses or shrubs if you don’t have a drain. Make sure to change the water when it becomes dirty and when a new crop is added. After dumping old water, refill the container with clean water, re-measure the sanitizer, and test for concentration.
Step 6. Monitor pH and sanitizer levels
To maintain levels that are appropriate for your sanitizer, use test strips or another method to verify the concentration after each addition of sanitizer. Make sure to read the entire label to find the correct PPM for your product. You can reach out to the manufacturer or Extension for help finding the correct PPM if needed. You can buy chlorine test strips at restaurant supply stores or online. Test strips for other products are generally available where those products are sold.
Read the label to determine what pH level is required. Generally, pH levels should be maintained between 6.0 and 7.0 to provide for the greatest effectiveness.
Step 7. Always document the sanitizer levels on a log sheet
Keep a log sheet with the date, time, and concentration levels near your washing station. You should check the sanitizer level in the water after each addition of sanitizer and document the level on the log sheet.
DO NOT add sanitizer at random times or in unmeasured amounts. This is not effective and the levels will vary greatly.
Sanitizers for produce wash water*
Chlorine-based sanitizers: Many formulations of bleach are approved for use in fruit and vegetable wash water. One common is hypochlorite such as Clorox Germicidal Bleach, EPA registration number 5813-111. The label indicates 25 PPM for fruit and vegetable rinsing. To achieve this concentration, mix 1/2 teaspoon of bleach for each gallon of potable water. Use a tester strip to verify this level. If you use a different formulation, read the label and follow those instructions.
To find a PPM in a different volume of water, or with a different concentration of chlorine-based sanitizer, use this online calculator.
Sanidate 5.0 from BioSafe: EPA #70299-19. Sanidate is a peroxyacetic acid (PAA) based sanitizer that is approved for use in organic production. PAA is a combination of acetic acid and hydrogen peroxide, and it breaks down readily in the environment. It does not react to organic matter in the same way as chlorine-based sanitizers, so the levels will stay stable for longer when washing dirty produce. Rates for fruit and vegetable processing water should be between 27- 96 PPM. It is available from Johnny’s, BFG Supply, Arbico Organics, or directly from the company. The Minnesota BioSafe Systems rep is Jessica Jacobsen, jjacobsen@biosafesystems.com, 320-212-3905.
Tsunami 100 from Ecolab. EPA #1677-64. Tsunami 100 is another peroxyacetic-based sanitizer. Call Ecolab Inc., 651-293-2233.
VigorOx 15 F&V EPA# 65402-3 from Evonik. VigorOx is a peroxyacetic acid and hydrogen peroxide-based sanitizer.
*These are commonly used sanitizers. This list is for information and should not be viewed as an endorsement of a product by the University of Minnesota.
Follow the label for the product that you are using. Do not trust other internet sources or factsheets to indicate the PPM to use. Sometimes a factsheet will indicate a level for food contact surfaces, rather than fruit and vegetable washing. Make sure to know your product and label.
Reviewed in 2024