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.
That typical Wednesday night is followed by my Saturday morning routine: Go to the farmers market, buy great stuff, come home, open refrigerator, slide out crisper drawer, throw (almost) everything away from week or two before, replace with new stuff. Lather, rinse, repeat.
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.
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.
Most fresh vegetables in the typical American diet are more than 90 percent water by weight.
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.
Kathleen M. Brown, professor of plant stress biology at Penn State University 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.
Fresh not soggy
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.
Most residential refrigerators 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 there are engineering and aesthetic design rationale behind that placement, out of sight is out of mind.
That’s why 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.
It’s common sense that the foods kept at eye level are the ones you will use most in your cooking, says Madison.