The Dark Side of your Supermarket’s Produce Department
Ever wonder how that supposedly fresh produce from far-off locales arrives in your supermarket looking as good as it does? We did, so we sent Phil McIntosh off to investigate. What he discovered may have you reconsidering where you get your fruits and veggies.
When shopping the produce aisles at your local megachain grocery store it’s hard not to be impressed with the apples so red and the oranges so orange. Zucchini and eggplants are large and unblemished, and the selection seems to go on forever. Everything looks fresh and healthy and the occasional spritz from a mister keeps lettuce and other greens looking their best. Based on appearance these must be the best-quality fruits and vegetables in the world, right? However, looks can be deceiving.
To maintain a consistent and reliable food supply, a vast network has been established that includes farmers, transporters, and retailers. Most fruits and vegetables aren’t grown in commercial quantity in most places with production localized to regions where the climate is suitable for large scale, extended-season growing. As a result, a lot of planning goes into getting products from field to table. The fact is, most produce has to be picked early, stored for a time, prevented from ripening or spoiling too soon, and shipped long distances, often under controlled conditions. As a result, the food is not nearly as fresh as it looks, or you might think (or hope) that it is.
Bananas are only grown in tropical regions, yet the banana bins in far northern or southern climes are seldom lacking. It takes large ships and trucks to deliver bananas from places like Honduras, Guatemala, and Ecuador. Shipping takes time and bananas quickly overripen. The solution is to pick them green, keep them cool during shipping, and then get them ready for the store in ripening chambers.
After several days journey in a container ship, the bananas are kept for a week or more under controlled conditions with the addition of ethylene gas, a plant hormone that encourages ripening. By the time you get to choose a bunch they can be anywhere from a few weeks to months old, depending on how the supply chain is working. If there is a glut of product, it may have to be stored longer until product is removed from inventory, or there can be shipping delays.
As far as bananas go, you really don’t have much of a choice when it comes to variety either, because the Cavendish, which is well suited to the mechanized production and shipping scheme, is pretty much in monoculture around the world, even though many would agree it is far from the best tasting banana.
And then there are apples. Unless you are picking them yourself at a local orchard, the ones you eat can be anywhere from nine to fourteen months old. How can that be? Apples only last a few weeks after picking when ripe, and it takes at least that long to get them from the orchard to the store, so something has to be done. And what is done is that they are picked when about ripe and then stored at low temperature for several months.
Ripening, which is enhanced by the natural production of ethylene by ripening apples, is blocked by the introduction of 1-methylcyclopropene gas. This same reagent is also used to slow the degradation of vegetables. The treatment does not make the product harmful, but over time the amount of vitamins, antioxidants and, yes, the flavor, of fruits and vegetables does decrease.
Many fruits and vegetables look so nice and shiny because they are coated with wax. The wax not only makes them look better but prevents dehydration. Wax has been used this way for hundreds of years. Most fruits and vegetables naturally have a waxy layer on their skin which tends to get damaged and worn off during harvesting and processing. Producers often use a thin layer of carnauba or beeswax, sometimes an alginate or carrageenan, or even a “shellac” obtained from insects as a protective coating. These substances do prolong shelf life, reduce wounding, and improve the appearance of produce, but they are not digestible, and provide no nutritional value. One of the most common treatment waxes, carnauba, is a palm product, and there has been a lot of discussion lately around the environmental damage caused by palm plantations.
- The Science of Sweet: How Fruit Ripens
- How to Grow 4 Types of Berries Hydroponically
- The Art of Growing Hydroponic Grapes
- Cultivating a Hydroponic Citrus Grove
So, the food in grocery stores is not all that fresh, and certainly does not taste as good as if it was. What else would do folks in the front office not want you to know?
There are many pesticides approved for use on conventionally grown fruits and vegetables to combat, weeds, insects, bacteria, fungi, and nematodes. Over a billion pounds of chemicals are applied to crops every year in the U.S. And, of course, much food is imported from other countries, some with a higher standard of pesticide vigilance, and some with less. Moreover, the U.S. tends to lag behind other nations in eliminating higher-risk pesticides from the market. Strawberries are a perennial leader in the race for the title of “most pesticide-contaminated food.” Also often coming in on the high side of pesticide residue analysis results are greens, stone fruit, grapes, and tomatoes. Not to focus only on the bad, corn, melons, and avocados are usually low in or essentially free of pesticide residues.
With careful shopping, one can find foods both safe and healthy at the local big-chain grocery store. But if you really want the best taste, most nutrients, and a greater variety for your table, shop local and organic. Better yet, grow it yourself.
Grocery stores would prefer you spent more money than less, and they’d rather sell an old grapefruit to you rather than throw it out. Here are a few well-known grocery store tricks.
Written by Philip McIntosh | Science & Technology Writer, Teacher