Freezing vegetables is a fast and easy form of food preservation, and most crops, such as asparagus, broccoli, green beans, peppers, summer squash, dark leafy greens and all types of juicy berries, will actually be preserved best if frozen. Part of the beauty of freezing vegetables is that you can easily do it either in small batches — thus making good use of odds and ends from your garden — or in one big batch of your homegrown harvest or peak-season, discounted crops from the farmers market. Unlike with canning, you don’t have to pay attention to acidity or salt when freezing vegetables. Instead, you can mix and match veggies based on pleasing colors and flavors — for instance, using carrots for color, bulb fennel for texture, and green-leafed herbs for extra flavor. You can include blanched mild onions in your frozen combos (a good use for bolted onions that won’t store well), but don’t include garlic, black pepper or other “seed spices,” which can undergo unwanted flavor changes when frozen.
The greatest amount of space in my freezer belongs to vegetables, mostly in freezer bags that stack nicely because I first freeze the vegetables flat on cookie sheets. I also allot freezer space for odd-shaped packages, such as those for cabbage leaves that have been blanched and frozen flat for making cabbage rolls in winter. I even steam-blanch and freeze an assortment of hollowed-out, stuffable veggies, such as pattypan squash, zucchini, small eggplant and peppers. By season’s end, the contents of my freezer reflect the full diversity of my garden.
Freezing Vegetables: The Basics
Only use fruits and veggies in excellent condition that have been thoroughly cleaned. Most vegetables you plan to freeze should be blanched for two to five minutes, or until they are just done. Blanching — the process of heating vegetables with boiling water or steam for a set amount of time, then immediately plunging them into cold or iced water — stops enzyme activity that causes vegetables to lose nutrients and change texture. The cooled veggies can then be packed into bags, jars or other freezer-safe storage containers. Fruits or blanched vegetables can also be patted dry with clean kitchen towels, frozen in a single layer on cookie sheets, and then put into containers. Using cookie sheets for freezing ensures that the fruits and vegetables won’t all stick together, thus allowing you to remove a handful at a time from the container.
Unless you’re freezing liquids — which require space for expansion — you should remove as much air as possible from within the freezer container. With zip-close freezer bags, you must squeeze out the air by hand, whereas a vacuum sealer will suck out air as it seals the bags. Vacuum sealing reduces freezer burn (the formation of ice crystals that refreeze around the edges of the food and damage its taste and texture) because the crystals have no space in which to form. To read more about freezer-safe container options, see “Can You Freeze in Canning Jars?,” later in this article.
According to the National Center for Home Food Preservation (NCHFP), fruits and vegetables will last in the freezer for eight to 12 months if prepared and stored properly. Vacuum-seal bags cost more than regular freezer bags, but devotees say they are worth the extra expense because they make frozen foods last even longer.
At one time or another, I have been so crunched for time that I stored excess tomatoes simply by washing them and tossing them in a freezer bag. This method provides plenty of tomatoes for soup or sauce, and frozen, whole tomatoes peel like magic if held under warm water. If you want to retain the skins for nutritional reasons, you can run half-thawed tomatoes through a food processor. (At this point, you’ll be glad if you cored the tomatoes before you froze them.)
Frozen, whole tomatoes take up lots of freezer space, and because the tomatoes will not have been heated before they were frozen, enzyme activity may cause some loss of vitamins and other nutrients. This won’t happen, however, if you gently stew your tomatoes in their own juice before freezing them. After removing cores and skins, which you can do by blanching them, bring the coarsely chopped tomatoes to a gentle simmer for about 10 minutes, or until the tomatoes are tender. Allow to cool. If desired, you can ladle off some of the juice from the top and freeze it separately. Removing some of the juice will give you a frozen product similar to diced or stewed tomatoes in cans.
You can also include selected veggies and herbs in the mix when freezing tomatoes, and let the simmering tomatoes serve as the blanching liquid. For example, you could add chopped peppers and cilantro to a batch intended for use as a chili base; combine okra, peppers and thyme in jambalaya mixtures; or throw in everything from eggplant to zucchini for veggie stews.
I freeze a few quart bags each of whole cherry tomatoes and stewed tomatoes along with dozens of tomato-based veggie mixtures, but the trick to having the best-tasting frozen tomatoes is to dry them halfway first, as is done in the Oven-Dried Tomato Recipe (later in this article). Removing some of the moisture from tomatoes intensifies their flavor, saves freezer space, and gives you the ideal tomato for pizza or pasta sauce.
Tip: If you have a small amount of tomato sauce left over from canning, keep it in the fridge and use it as a broth when freezing vegetables, such as summer squash or eggplant.
How to Freeze Green Beans
You can freeze most types of snap beans, including yard-long beans. The more substantial the bean, the better the finished frozen product. For example, pencil-thin filet beans soften too much when blanched and frozen, but bigger, firmer green beans are fine freezer candidates. Most pole beans freeze especially well, but my best batches of frozen beans come in fall, when I slow-cook savory shelly beans and freeze them.
After blanching your green beans, you can put them directly into freezer containers, or pat them dry and pre-freeze them on a cookie sheet first. You can also freeze shelly beans in their cooking juices. When cooking thawed green beans, try using “dry” cooking methods, such as braising them in a little butter or olive oil, or making green bean oven fries.
Tip: Purple-podded bean varieties can be used as blanching indicators on freezing day. Their purple hue will change to green when the beans are perfectly blanched.
How to Freeze Peppers
Opinion is divided over whether blanching is required when freezing peppers. Chopped, raw peppers stashed in freezer-safe containers will keep nicely for several months, but you can also try other methods for freezing peppers. I often cut ripe sweet peppers into halves or quarters for stuffing, then steam-blanch and freeze the pepper “boats” individually on cookie sheets. After they’re frozen, they can be nested together and packed in freezer bags. If I run out of chopped peppers, I start using the peppers I set by for stuffing.
Some peppers have wonderfully complex flavors that intensify if the peppers are roasted, grilled or smoked before they’re frozen (for a Fire-Roasted Peppers Recipe later in this article). Roasted peppers cooked over a hot fire until just done and then stashed in freezer bags are among the best-tasting foods produced by my garden and kitchen.
Tip: Always wear protective gloves when handling hot peppers. Putting on gloves is much easier (and less painful) than removing capsaicin — the compound that makes peppers hot — from your hands.
Saving Summer Squash
Despite their beauty and productivity, summer squash — including zucchini, yellow squash and pattypans — are lightweights in the flavor department. They’re also prone to degradation from enzyme activity, so they must be thoroughly blanched before they’re frozen. I like to hollow out single-serving-sized pattypans and zucchinis for stuffing, and then steam-blanch them before freezing.
The standard procedure for freezing summer squash is to blanch half-inch slices in boiling water or steam for three minutes. Because I’ll use most of my frozen squash in casseroles or soups, I often add more colorful vegetables and herbs to bags of frozen squash — for example, chopped basil, sliced carrots and ribbons of kale. When thawed, the squash mixtures seem like summer in a bag.
Another method for freezing summer squash is to slice zucchini horizontally into large, flat slices before blanching. These can be grilled or used to make roll-ups. You can also freeze blanched and grated squash to add to all kinds of baked goods.
How to Freeze Corn
When we asked the MOTHER EARTH NEWS Facebook community about their favorite ways to freeze sweet corn, many respondents raved about the flavor of sweet corn that had been frozen raw in the husks, as described by Arkansas reader Betty Heffner: “The best method I’ve found is to pull back the husks to remove the silks and cut off any damage from the tips, then smooth the husk back over the corn before freezing it.” Many folks attested that this easy method preserves fresh corn flavor for six months, though it’s not among the approved processes for freezing corn listed by the NCHFP.
Experts recommend blanching sweet corn before freezing it, which locks in taste, texture and nutrition. You can freeze whole, blanched ears if you have freezer space, or cut the kernels from blanched, cooled ears and freeze only the kernels. I like to cut the kernels raw, press out some juice, and bring the mixture barely to a simmer before cooling and freezing it. I then compost my cobs, but a tip from Carolyn Vellar of Kansas City, Mo., made me realize I’ve been doing so prematurely. Carolyn simmers her bare cobs to make corn broth, which she freezes for use in winter soups.
New Mexico reader Diana McGinn Calkins freezes kernels cut from blanched, cooled ears when she has no freezer space left for raw ears in the husk. “I get as much air out as possible and then flatten out the bag of corn. Once frozen, I break it up and put it back into the freezer. Then I can take out as much as I want.”
For sweet corn that’s ready to heat and eat, try this easy roasting method from Katrina Steele of Howard, Ohio: “We cut the corn off the cob and pile it in a big pan with a stick of butter and enough milk to cover the bottom of the pan. Then we bake it at 350 degrees Fahrenheit until piping hot, stirring every 10 minutes. After it cools, we spoon it into freezer bags. Tastes wonderful!”
Can You Freeze in Canning Jars?
A few summers ago, a visiting friend was aghast when I poured blackberry juice into a canning jar and screwed on a used lid before stashing the container in the freezer door. She said I had broken two rules: freezing in canning jars and reusing canning lids. But some rules can be carefully broken. You can freeze in clean canning jars as long as you leave plenty of headspace, because liquids expand as they freeze. I leave 11⁄2 inches in pints and 2 inches in quarts.
Used lids should never later be reused for canning, as these can’t be trusted to form a sound seal. But you don’t want a seal when freezing in canning jars. I screw lids on loosely at first, and then tighten them after the jars have frozen solid. I mostly use canning jars for freezing fruit and veggie juices, which are messy to handle in bags. I also use canning jars for freezing dried veggies, which will last two years in the freezer but only about one year on a pantry shelf.
You may opt to freeze your produce in glass containers if you’re concerned about chemicals that can leach from plastics onto your food. Most freezer bags are made of No. 4 LDPE (low-density polyethylene), which is not known to leach chemicals. If you’re worried about putting hot food into plastic, however, wait until the food cools before packing it into bags. Learn more about safely storing food in plastic.
Flavor-Packed Freezer Recipes
Oven-Dried Tomato Recipe
You can make these delicious morsels in an oven, in a food dehydrator, or out in the sun on a dry, sunny day.
If using your oven, preheat it to 250 degrees Fahrenheit. Wash and dry ripe tomatoes. Cut paste tomatoes and cherry tomatoes lengthwise in half. Cut slicing tomatoes into quarters. Arrange the prepared tomatoes — with the cut sides facing up — on baking sheets that have rims to catch any juices. Sprinkle with sea salt. You can season the tomatoes with fresh herbs and a light drizzle of olive oil. Place in the oven for 1 hour, then reduce heat to its lowest setting. Dry for 2 more hours, or until the tomatoes flatten and the edges pucker.
When using a dehydrator, dry the tomatoes for about 4 hours.
To dry your tomatoes in the sun, lay them out on a screen or in a solar dehydrator (to build your own, see Build a Solar Food Dehydrator) and leave them outside in full sun until they have fully collapsed. If your tomatoes are exposed, cover them with a light cloth to deter bugs.
Freeze your half-dried tomatoes on cookie sheets, and then pack them into freezer-safe containers. Fully dried tomatoes take longer to dry, and won’t need to be frozen.
Fire-Roasted Pepper Recipe
Wash peppers and cut out any blemished spots.
Place whole peppers on a hot grill or under a hot broiler. Use tongs to turn peppers as needed until they’re blistered on all sides, with brown and black patches.
Place the hot, roasted peppers in a large pot with a lid or enclose them in a paper bag. Allow them to cool. When the peppers are cool, use your hands and a table knife to remove loose pieces of skin. Cut peppers in half and remove cores. Freeze the roasted peppers on cookie sheets and then pack into freezer-safe containers. Roasted peppers can be used for dozens of recipes.
If you’re in a hurry, you can freeze whole, roasted peppers and then remove the skins by dunking them in warm water after they’ve been frozen. Their warm-water dunk makes them easy to chop, too.
Contributing editor Barbara Pleasant gardens in southwest Virginia, where she grows vegetables, herbs, fruits, flowers and a few lucky chickens. Contact Barbara by visiting her website or finding her on Google+.