Food Waste: Keeping Greens Green
While the world remains stuck at home, we all find ourselves both cooking more, entertaining less, and (hopefully) trying to limit the number of trips we’re making to the store. This has created a bit of a pileup in my produce drawer, with no dinner party salads to offload the odd bunch of scallion or mint left from another dish. We’re all also a bit extra sensitive to sanitation these days, with the dry hyper-washed knuckles to prove it.
So as we have fewer opportunities to share, less money to spend, and more time to handle our ingredients, it is a great time to walk through a few practices to extend the shelf life of all the green things gracing your kitchen. Hopefully, these tips for leaf vegetables and herbs will help you reduce waste, stay safe, and save money. It’s a bit of a pain, and you may create a bit of waste in the process in paper towels and plastic bags (though you can of course use cotton towels and reuse the bags)! But at some point between shelf and mouth, you’re going to wash all this anyways –– and by doing it as soon as you bring it home, you’ll end up with longer-lasting produce and less work when you’re ready to get cooking.
Here, we’ll walk through spoilage science, how to best clean your produce, and storage tips for common herbs and greens.
Storage Science
When we’re trying to increase the longevity of produce, we’re trying to control four things:
Microbes: When you bring a piece of produce into your home, it’s had the chance to pick up microbes from the field, farmers, transportation network, shopping cart, grocery conveyor, bags, counter, etc –– and over its purchase day, that produce will encounter whiplash of humidity and temperature which just might kickstart the growth of a microbe that will greatly reduce its longevity.
Moisture: we want to maintain roughly the same moisture conditions as when the plant was growing. Too much water, cells may burst and turn slimy. Too little water, and the water stored in cells dry up and the cells collapse, causing the plant to wilt.
Temperature: all foods contain scores of bacteria, which are generally 4-5 times more active at room temperature than at refrigerated temperatures. We’re trying to keep foods as cool as we can without going so cold that some water freezes, damaging the cells and creating a soggy, limp mess. Remember that fridges cycle temperature, oscillating the cooling element such that certain areas and moments will be dramatically colder than the rest.
Light: too much light after picking degrades chlorophyll and turns plants yellow.
Additionally, you’ll want to pay attention to putting your greens near apples, bananas, or ripening avocados, which produce ethylene and can speed up the breakdown of more delicate produce.
In most cases, we can address all of these risks in one process by rinsing, enclosing, and refrigerating. So let’s dig into a surefire process to batch this up once your greens come home.
Processing
Setup
Largest bowl / pot you have, or the bowl of your sink filled with cold water
By filling a vessel instead of rinsing, you reduce the risk of damaging delicate produce with direct pressure from the sink
Salad spinner
Baking sheets lined with paper towel or dish towels
If you’re using dish towels (which I recommend!), just note it’ll take longer for things to dry
Storage containers per the below (plastic bags, glass lidded containers, tall jars)
Generic Cleaning Process
Place the herb / greens into the bowl or pot a handful or two at a time. Gently swirl them in the water then transfer delicately to the salad spinner.
Once spun dry, transfer to baking sheets or counter lined with towel in a shallow layer. If space is tight, you can put a layer of towel above the greens and then place more on top of that paper, with up to 2 or 3 layers sandwiched together.
After spinning, pour the salad spinner liquid down the drain, and repeat.
Now, let’s apply this generic process to rugged and delicate categories of both herbs and leaf vegetables.
Storing
Herbs
Rugged herbs
These drier, woodier herbs need just a bit of moisture to keep their cells from wilting. Keep these wrapped in a damp paper towel in a plastic bag.
Rosemary
Thyme
Sage
Chives
Scallions
Delicate herbs
The cells of these herbs collapse quickly if they lose too much water, so these should be kept in a damper environment. Ideally, these would be placed in a bit of water in a glass with a plastic bag over the top to ensure the leaves are also in a humid, clean environment. Before placing in water, be sure to trim the bottom of the stems and remove any leaves which would be submerged.
Parsley
Cilantro
Dill
Mint*
Basil*
* Mint and basil are unique in that they are slightly better off at room temperature than in the fridge. Treat these herbs like a bouquet of flowers, in water and on the counter.
One last note on delicate herbs — if they do seem to be within a day or two of collapse, make them into a salsa verde or other herby sauce.
Salad Greens / Leaf Vegetables
Crunchy greens
These robust greens are a bit tricky, as you want to wash them to rinse off any dirt or microbes but also don’t want to trap too much water in the folds. Generally, trim the root end, rinse, and dry thoroughly.
Romaine
Head lettuces (cabbage, iceberg): do not wash; store in a loose plastic bag with a paper towel.
Delicate greens
Handling delicately, rinse these in the water bowl, spin, dry on towels, and place in a plastic bag or hard container with a paper towel.
Mâche / lamb’s lettuce / feldsalat
Spinach
Arugula
Butter lettuce: I like to core and separate the leaves and wash thoroughly upon bringing them home.
If you’re looking at bitter greens like arugula or spinach that are nearing the end of their fridge life, mix them into a quick pesto — equal weights of chopped nuts, grated parmesan, and greens blended together with some salt, garlic, and ample olive oil drizzled in, these pestos are great with pasta, bread, or with raw crunchy vegetables.
These practices should help extend the life of greens from a few days to (in some cases) a few weeks, helping you reduce waste, eat healthy, and avoid trips to the store. There’s a world of tips for fruits and vegetables that are also plant-specific (carrots go in water in the fridge, tomatoes sit on the counter unwashed), but as a rule the quickest-spoiling produce are these greens and herbs. A great place for us to chip away at the amount of waste we produce!
