Fruits and Vegetables--What Should You Buy?

To me, one of the great things about early fall is the arrival of fresh local apples.  The kind that taste like you just picked them off the tree.  At our farmers market over the weekend, I tasted an apple sample that put a smile on my face--crisp, tart, so yummy!  As I was filling my bag with these lovelies, I overheard another customer ask the farmer if the apples were organic.  He replied, "No, we used integrated pest management."  Without so much as a 'thank you', the woman turned on her heel and strode off.  All I could think was " You don't know what you are missing!"  But the farmer did himself no favors as he missed an excellent opportunity to educate a customer. 

Local peaches, tomatoes, and pears

Faced with a myriad of choices at the grocery store and farmers markets, how do you chose the best fruits and vegetables for your family?  How does organic compare to conventional?  What is integrated pest management?  Fresh vs. frozen or canned?  Does washing fruits and vegetables matter and how do you do it?  Let's get started with some answers!

Organic versus Conventional

While 'natural' is an unregulated term, there are very specific requirements for food to carry the USDA Organic label.  By USDA definition, organic means:

• Produced without excluded methods (e.g., genetic engineering), ionizing radiation, or sewage sludge.
• Produced per the National List of Allowed and Prohibited Substances.
• Overseen by a USDA National Organic Program- authorized certifying agent, following all USDA organic regulations. 

 Food can be labeled with the USDA certified organic label if they are '100% organic' or 'organic' (meaning basically 95% of the ingredients are organic).  'Made with organic' can be used if 70% of the food is made with organic ingredients, but cannot carry the USDA certified organic label.

In many grocery stores, the certified organic produce is more expensive than conventionally grown fruits and vegetables.  Is the premium worth it?  To decide what is best, it is helpful to examine the question in two ways: nutrient quality and pesticides.

Nutrient Quality

Conventional farmers argue that there is no significant difference in the vitamins, minerals and phytochemicals found in conventional vs organic produce.  But organic advocates beg to differ.  Unfortunately, the science is unclear.  While a 2009 American Journal of Clinical Nutrition review of 55 studies found no difference, organic proponents took issue with the methodology.  A 2014 study did find a difference in phytochemicals, with organics having more.  But, again, critics took issue with the study, particularly that any health benefit of the observed increase in phytochemicals.  Sadly, the ongoing debate doesn't help the average consumer. 

However, as I researched this topic, I was struck by the number of articles that outlined or mentioned how other factors, in addition to organic vs conventional, influenced mineral, vitamin, and phytochemical content.  For example, different species and even different cultivars have different profiles of phytochemicals.  Post-harvest handling--transportation time, storage, freezing, canning--also influences the nutrient profile.  And surprising to me is that sometimes phytochemicals increase with the post-harvest handling! 

My take-home on nutrient quality is that there may be a difference between organics and conventional produce, but not enough to influence buying decisions.  However, when selecting fruits and vegetables it is perhaps helpful to expand beyond your usual rainbow, integrating a new varieties of fruits and vegetables into your diet.

Pesticides

In my mind, this is where the rubber meets the road on organics.  Simply put, conventionally grown fruits and vegetables use synthetic pesticides.  Organic certification restricts the kind and type of pesticides and, as a result, organic produce has a lower level of pesticides.  In 2012, the American Academy of Pediatricsurged pediatricians to educate parents about pesticides in their children's food, noting that "Children encounter pesticides daily and have unique susceptibilities to their potential toxicity." 

The Environmental Working Group (EWG), using data from the USDA and FDA, have complied lists of those conventional fruits and vegetables with the most and least amounts of pesticides, otherwise known as the Dirty Dozen and the Clean 15.  For the Dirty Dozen, the EWG suggests buying organic when possible to limit pesticide exposure.  The Clean 15's lower levels of pesticides makes conventional produce a good choice. 

• Dirty Dozen--apples, strawberries, grapes, celery, peaches, spinach, sweet bell peppers, imported nectarines, cucumbers, cherry tomatoes, imported snap peas and potatoes
• Clean 15--avocados, sweet corn, pineapples, cabbage, frozen sweet peas, onions, asparagus, mangoes, papayas, kiwis, eggplant, grapefruit, cantaloupe, cauliflower and sweet potatoes
• Dirty Dozen Plus--This category is for leafy greens (kale and collard greens) and hot peppers.  The pesticides on these vegetables are at low levels, but are contaminated with pesticides that are toxic to the nervous system.

Frankly, the Dirty Dozen list is enough to make you run screaming from the produce section of your grocery store!  But keep a few key facts to keep in mind:

• Wash your produce.  When the USDA processed the samples, they were washed or peeled to mimic consumer behavior.  As a result, the pesticide load may be higher on unwashed produce (more on washing below).
• Cook your produce.  Cooking reduces the levels of pesticides.
• Still eat your fruits and vegetables.  Even the EWG, a group with a clear opinion on pesticide matters, urges consumers to eat fruits and vegetables, even if conventional is your only choice.  Far better to eat the conventional apple than the donut!
• Data may not be current.  EWG relies on USDA sampling data to compile their lists.  Some items like strawberries, celery, and kale, have not been testing since 2008.  We can hope that future sample testing leads to a reshuffle of the Dirty Dozen.
• GMO-fruit and vegetables are limited.  If you are concerned about GMO in the produce aisle, know that the produce does not have to be labeled (and probably won't be).  That said, there is not a lot of it.  According to EWG, some zucchini and yellow squash are genetically engineered, along with some sweet corn.  Non-organic papayas grown in Hawaii are pretty much all GMO.  If you want to avoid GMO produce, buy organic.

Eating Local

The EWG lists focus on conventional fruits and vegetables, offering organic as an alternative.  But talk to your local farmers at the weekly farmers market and you will find there is a third option.  I spoke with several farmers selling at my market.  Both, and many others, use integrated pest management (IPM).  What is IPM?  As I listened to the farmers and read this great description from one orchard, I realized IPM is a middle ground.  These farmers still use pesticides when necessary, but try other things first like mating disruption for moths and planting more hardy fruit. 

One pesticide highlighted by the EWG in their Executive Summary was diphenylamine (DPA).  DPA has been banned in the European Union, but is applied to most conventionally grown apples and some pears in the US to prevent fruit skin discoloration.  In my conversation with two local apple farmers, neither applied anything to their apples post-harvest.

In her book What to Eat, Marion Nestle notes her personal priority list is "(1) organic and locally grown, (2) organic, (3) conventional and locally grown, (4) conventional" (page 66).  For me, I would move 'conventional and locally grown' to the number 2 spot.  The produce is likely tastier, leading my family to eat more.  And, if I can talk to my local farmer, I can come away with a better understanding of their version of conventional.

Fresh, Frozen, or Canned?

One article I reviewed looked at vitamin C content as a marker to compare fresh and frozen fruits and vegetables.  Examining peas and broccoli, the vitamin C levels were similar between fresh-from-the-store and commercially frozen.  Interestingly, peas stored in-home for several days were not as good as frozen!  This study and others have demonstrated that frozen and canned vegetables and fruits, processed at their peak, offer nutritionally sound (and sometimes less expensive) alternatives to fresh produce. 

In selecting canned and frozen items, be sure to read the label.  Some frozen vegetables, for example, contain added salt.

Washing

My biggest at-home change this week from my research will be washing produce.  As noted above, the USDA samples used by EWG were washed and peeled as done at home.  So with no washing, the levels are sure to be more.  But how to wash? 

Just washed tomatoes, ready to be dried

From Foodsafety.gov:

• Cut away any damaged or bruised areas.
• Rinse produce under running water. Don’t use soap, detergent, bleach, or commercial produce washes.
• Scrub firm produce—like melons or cucumbers—with a clean produce brush.
• Dry produce with a paper towel or clean cloth towel… and you’re done. 
• The good news? Bagged produce marked “pre-washed” is safe to use without further washing.

And from the University of Maine Cooperative Extension, a few more tips:

• Produce with a lot of nooks and crannies like cauliflower, broccoli or lettuce should be soaked for 1 to 2 minutes in cold clean water.
• Some produce such as raspberries should not be soaked in water. Put fragile produce in a colander and spray it with distilled water.
• Drying clean paper towel can remove more bacteria.

Foodsafety.gov and other sites made a point to emphasize that it is important to wash all fruits and vegetables, even those you are going to peel.

After reading Foodsafety.gov, I still wondered about the various commercial washes.  Thankfully, the University of Maine Cooperative Extension article cover this issue.  They compared rinsing with distilled water to a Proctor and Gamble product and two other treatments.  Their finding?  Distilled water was as good or better than the alternatives!  While distilled or bottled water is great because it is filtered and purified, they also note very clean cold water works as well.

 Local Tomato Sauce--washed and cooked!

First step?  Washing and drying the local Roma tomatoes, of course!

With generous pour of olive oil, I cooked one white onion and two cloves of garlic, roughly cut, over low heat.  When the onion was getting clear, I started adding the tomatoes.  I cut the Roma tomatoes into rough quarters and dropped them into the pot as I went.  Once the tomatoes were in, I added about a teaspoon of Italian seasoning and 1/2 teaspoon of Kosher salt. 

Then on went the lid and they simmered at low heat (with occasional stirring) for about 30 minutes.  Next, the lid came off (to try to get some liquid to evaporate) and I dialed the heat down to a true simmer. 

After another 20 to 30 minutes, it was time for the blender!  A quick spin around the blender on the puree setting made for a simple tomato sauce to top our evening's linguine!  The extra was frozen for another day.