A typical Wednesday night at my house goes something like this: Open refrigerator, take lettuce and other vegetables out of crisper, see that most of them are wilted, return them to refrigerator. Realize meat isn’t defrosted, whip out iPhone, order Thai food delivery.
By my back-of-the-envelope calculations, I’ve thrown away just over $1,200 in produce so far this year. I’m not proud of that.
In fact, I’m pretty embarrassed. When I buy meat, I use every bit of it, including the bones for stock. Why am I so careless with produce?
I’ve made a real effort to break this bad habit. I try to eat vegetables with every meal. Still, Swiss chard and romaine lettuce leaves droop and sag after a few days at home, and there are only so many stir-fries and soups one can make when carrots, green beans and asparagus get bendy. Sometimes you just crave something fresh and crunchy without wanting to drive to the grocery store or wait a few days for the next farmers market to open.
I wish I had the time and lifestyle to shop for food every day. But even if I did, a one-person household takes longer than a family of four to go through a head of lettuce or a bunch of carrots. Even when I’m trying, vegetables often wilt before I can manage to get to them.
With a firm resolve to save money and be respectful of the farmers who grow the produce I eat, I’ve been on a mission to extend the “fridge life” of my vegetable staples. So I turned to the experts to learn more about how to revive what I’ve got and better store what I buy.
“Water is everything.”
That's what Bernard Boyle of Garner's Produce tells me at the 14th and U Farmers Market on a sunny Saturday morning. He's right. We all learned in high school biology that the human body is about 60 percent water. What I've discovered in my let's-try-not-to-be-so-wasteful vegetable research is that plant foods have us beat: Most fresh vegetables in the typical American diet are more than 90 percent water by weight, according to Nathan Myhrvold and the team that wrote the epic food science and technology tome "Modernist Cuisine: The Art and Science of Cooking" (The Cooking Lab, 2011).
For example, they found that a carrot is roughly 88 percent water, nearly the same proportion found in milk. A fresh cucumber contains a higher proportion of water than some mineral-rich spring waters. Swiss chard is 94 percent water.
In "Keys to Good Cooking: A Guide to Making the Best of Foods and Recipes" (Hodder and Stoughton, 2010), food science expert Harold McGee writes that fresh vegetables and herbs gradually deteriorate as they use up their limited water reserves after harvesting. That makes sense. But can you give them a little boost before they cross over to the rotten side, and if so, how?
Consumer advice about reviving vegetables runs the gamut: room-temperature water vs. ice water; submerging the whole vegetable or soaking just the ends; adding salt, sugar or vinegar to the water. Chefs, food companies, scientists and food bloggers offer a variety of methods juggling time, temperature and those additives, with the one commonality being water.
Kathleen M. Brown, professor of plant stress biology at Penn State University, teaches a post-harvest physiology class and has researched this topic. Her advice: All you need is water.
“Additives actually reduce the difference in osmotic potential between the vegetable and water and reduce the rehydration rate,” she says. “Besides, you don’t need those flavors.”
Air and water temperature matter during the revival process, Brown advises. “When the air temperature is lower, the vapor pressure deficit — the driver of moisture loss — is smaller.” She tells me I should soak vegetables in cold water from the tap to revive them, and do so in the refrigerator instead of in my warm kitchen.
For vegetables that have a heavy cuticle, or waxy exterior layer that might not admit water as quickly — Swiss chard and celery are examples — Brown suggests trimming the stems and putting them in a glass or vase of water, as you would fresh-cut flowers.
How do you know when they’re refreshed? “When the vegetables are well hydrated, there is a higher pressure in the cells, and they break and release moisture more easily when you chew, so they seem crisp,” says Brown.
Can vegetables be over-hydrated? Sort of. Gardener and chef Deborah Madison, whose latest book is "Vegetable Literacy" (Ten Speed Press), cautions that when you wash or revive leafy greens such as lettuce, kale or chard, you need to dry them thoroughly if you're not going to use them right away: Water remaining on the outside invites bacteria. In fact, she breaks apart her lettuce and other leafy greens, rinses and dries them, then stores them in a plastic bag with a clean, dry dish towel or paper towels to absorb any remaining moisture on the leaves.
But then what? After we get all that water back in vegetables, the refrigerators we put them into take it out all over again.
“In basic refrigeration, the cooling system is in the freezer, and the refrigerator gets its cold air from the freezer,” says Michael Mattingly, senior refrigeration product manager at GE. “The colder you make your freezer air, the more humidity is stripped out.”
Mattingly explains that humidity in refrigerators comes from two sources: outside air flowing in when you open the refrigerator door and humidity given off from fruits and vegetables inside. New, high-end refrigerators have dual-evaporation systems: separate cooling systems for the freezer and the refrigerator, allowing for better humidity control. And most residential refrigerators also have some level of adjustable humidity control in the crisper drawers that the owner’s manual or product Web site should give guidance on how best to use. Just know that although adjusting the drawers’ humidity can help with storage, it won’t stop the vegetables’ natural process of losing moisture.
The challenge for many consumers, myself included, is that crisper drawers are at the bottom of the refrigerator. Though Mattingly explains the engineering and aesthetic design rationale behind that placement, and it makes perfect sense, out of sight is out of mind.
Madison keeps flours, grains, nuts and dried fruit in her refrigerator crisper drawers — not vegetables.
"I store vegetables in plastic bags on the shelves in my fridge, and it works just fine," she says. Keeping them in plastic bags provided by vendors gives vegetables a better chance at lasting longer.
It’s common sense that the foods kept at eye level are the ones you will use most in your cooking, says Madison. If you’ve lost sight of vegetables and they have wilted, it’s worth trying to rehydrate them. But if they’re past the point of no return — if your produce has changed color, is covered in dark spots or has discolored, liquefied, become slimy or generated obvious bacterial or mold growth — discard them.
Better yet, “compost them!” says Madison. “Returning them to the earth should make you feel less guilty.”
Blymire is a freelance writer and author who lives in Takoma Park. She'll join today's Free Range chat at noon: live.washingtonpost.com.
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