Best way to wash fresh produce

Organophosphorus pesticides are often detected in conventionally grown Australian produce. Why is it important to minimize our exposure to these compounds? These pesticides have been associated with endocrine dysfunction, male infertility, compromised foetal development, lower IQ, Parkinson’s disease and cancer. Organically grown foods may provide safer options. But their availability is often limited, they cost substantially more and may not be affordable for everyone.

We can be sure that the many health benefits of consuming fruits and vegetables outweigh the risks associated with pesticide residue exposure. But, is there a way to minimize our exposure to these pesticides that does not cost a fortune? YES, there is! I decided to write this article to provide a few practical suggestions. First, simply rinsing and rubbing your fresh produce under running tap water removes about 50% percent of pesticide residues. Researchers compared rinsing lettuce, strawberries and tomatoes under running water with soaking the produce in the sink with vegetable and fruit wash products, and soapy water (adding 5 g dishwashing liquid). They found no significant difference in the level of pesticide residue removal. Soaking fruits and vegetables using fruit and vegetable wash products or dishwashing soap do not increase residue removal compared to rinsing with plain water. No need to waste money on special products. What about adding vinegar to the soaking water?

Comparing rinsing with plain water, vinegar and salt solution

Soaking potatoes in plain water removes about 2 to 13% of pesticide residue.

Rinsing cabbage with plain water for 20 mins removes between 15-19% of residues.

Vinegar-water solution – soaking for 20 minutes:

 Adding diluted vinegar from the grocery store (5% acetic acid concentration) does not enhance pesticide removal significantly. However, adding a 10% vinegar concentration to the soaking water:

Potatoes: between 80-100% of pesticide residue was removed.

Cabbage: between 65-75% of pesticide residue was removed. If the cabbage is stir-fried, the cooking process enhances removal to 100%.

Salt-water solution – soaking for 20 minutes: reduces pesticides between 67-74%.

 Full-strength vinegar (10% acetic acid) is not cheap. However, sea salt is even cheaper than vinegar and can remove up to 80% residue of some pesticides. Cooking further reduces pesticide residue. It turns out a 10% salt-water solution may offer the best way to wash our fruits and vegetables. Plain cooking salt is cheap and very easily accessible pretty much anywhere. You need to prepare a 10% salt-water solution by dissolving 9 parts water to 1 part salt and soak fresh produce for 20 minutes. Fruits and vegetables need to be thoroughly washed after soaking to remove salt residue.

 

 The Dirty 12 and Clean 15 list

Have you heard of the The Dirty 12 and Clean 15 list? To help consumers in choosing safer foods and minimize exposure to pesticide residue, the Environmental Working Group (EWG) publishes an annual shopping guide list of fruits and vegetables, known as the “Dirty Dozen” and “Clean Fifteen”, listing the twelve foods reportedly having the highest pesticide residue levels and the fifteen foods having the least contamination levels. EWG recommends choosing organic counterparts for the Dirty Dozen list whenever possible. Organic farming uses natural pesticides. Hence, organic produce still have pesticides residue and requires washing. The Dirty 12 and Clean 15 lists are based on US farmed produce, but the list can still be useful to us. A lot of pesticides commonly used in US are also used here in Australia. There is no need to feel intimidated by these lists. I believe it is good to know which crops have higher contamination levels, so we can make sure we wash our produce to minimize our exposure. As discussed previously, soaking produce on 10% salt or vinegar-water helps to reduce our exposure to pesticides significantly.

“Good food on a tight budget” shopping guide is another useful publication from EWG, the guide lists cheaper and most nutritious vegetables, tips to save when shopping and planning meals, cooking, storage and pantry staple tips and recipes. Fresh fruits and vegetables provide numerous health benefits and we should eat plenty of these daily. When shopping, give preference to produce available seasonally, shop at the local farmer’s markets, and try growing some of your own herbs and vegetables at home. It is so satisfying to pick your own herbs, leafy green vegetables and fruits any time you need.

You can access the The Dirty 12 and Clean 15 lists: https://www.ewg.org/foodnews/

Good food on a tight budget shopping guide: https://www.ewg.org/goodfood/

 

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