Better than fresh? Your garden isn't producing yet, but never fear: canned and frozen fruits and vegetables are nutritious, convenient, and—as these recipes show—delicious

Natural Health, April, 2005 by Phillip Rhodes

FRESH IS BEST. That's the mantra of foodies who slaver over hand-plucked delicacies delivered from pastoral Edens. Nutritionists often follow lockstep, armed with pamphlets depicting a bounty of use-it-or-lose-it produce that could feed the population of Iowa, cows included.

Fortunately for the time- and money-pressed, fresh isn't always best. Sometimes, in fact, fresh isn't even fresh.

"A canned product can be just as nutrient-rich as a fresh one--and in some cases even more nutritious," says Patricia Kendall, Ph.D., R.D., professor of food science and human nutrition at Colorado State University. Ditto for frozen foods.

In this transitional season--we're hankering for summer produce, but have weeks to wait--that's good news. But it's also sort of shocking. "We're so used to thinking of fresh as the gold standard," says Dawn Jackson Blatner, R.D., a dietitian at Northwestern Memorial Hospital Wellness Institute and a spokeswoman for the American Dietetic Association.

"Convenience foods" seem like the relic of an age when cars didn't have seatbelts and tobacco companies sponsored track meets. How can whipping up a side of canned yams for dinner really be good for you?

shipping news

MODERN AGRICULTURE has grown very efficient--and very centralized. Temperate states produce many of the fruits and vegetables that reach our tables--for example, a third of the fresh tomatoes we eat each year come from California, and a third of those are raised in San Diego and Fresno counties. "Even though we have parts of the country that can produce year-round, a lot of fruits and vegetables are shipped long distances," Blatner says. "And foods that are sitting around a long time after harvest lose nutrients."

From root to fruit, a plant is a single living thing--and any vegetable or fruit begins to die the moment it's torn from the stem. "The plant is not photosynthesizing," says Alfred Bushway, Ph.D., professor of food science at the University of Maine. "It's still living tissue, but it's slowly dying as natural enzymes get released from ceils and begin to break down."

So how did that lustrous tomato come to be stacked atop a ruby-red pyramid in your local grocery store? Someone in California probably picked the fruit weeks ago. From the field, it was trucked to a cold-storage facility, then forwarded to stores and eventually dinner tables nationwide.

But the tomato wasn't idle: During the journey from field to table, its nutrients were slowly expiring. Within seven days, the tomato could have lost half its vitamin C, according to U.S. Department of Agriculture research. And if a fruit or vegetable isn't refrigerated quickly after harvest, nutrients can vacate the scene in a day or two.

saving grace

PRESERVING FOODS--whether in your grandmother's Ball jar, a can, or a freezer bag--essentially halts this nutrient degradation. After it's cleaned, produce destined for the cannery gets a quick bath in boiling water to set its color. Next it's sorted, placed into cans along with water and salt or sugar, then sealed and cooked at high temperatures for 12 to 14 minutes or more to kill any lurking germs. "Canning uses temperature to [neutralize] naturally occurring enzymes that would result in breakdown of tissue," notes Bushway.

There are losses. Some water-soluble nutrients, such as vitamin C and folate, don't fare well--the liquid cooks them away. According to a study at Cornell University, two minutes of blanching can cut vitamin C levels in a tomato by 10 percent, while 15 minutes of cooking causes them to drop by 15 percent.

But other nutrients thrive during canning. Carotenoids--the beta carotene, lycopene, lutein, and zeaxanthin found in orange, yellow, and red produce--are made more effective by heat processing. The Cornell study found that levels of lycopene, an antioxidant found in tomatoes, rose by 54 and 171 percent, respectively, after the two-and 15-minute cooking times. In a study of canned corn, also at Cornell, levels of antioxidant compounds rose by as much as 550 percent after processing.

"When heated, these plant chemicals become more digestible and usable by the body," Blatner explains. "So canned pumpkin, sweet potatoes, carrots, corn--all potentially have more phytochemical actions." And that results in more protection against cancer and heart disease.

getting the goods

THE CATCH is that canned produce can also pack a high-sodium punch. Canned peas, for example, contain about 300 milligrams of sodium per 1/2-cup serving--that's more than 100 times the amount found in unsalted fresh-cooked peas. Even though sodium works preservative wonders, it's added for another reason altogether. "Most added sodium is there for flavor," Blather says. One way to keep sodium levels down is to purchase "no-salt-added" canned veggies. "Or you can rinse the food before cooking, and 30 percent to 40 percent of any added sodium washes down the drain," notes Blatner. (This trick also works for fruits canned in sugary syrup.)

No matter how they're packaged--short of being drowned in butter or baked into pies--fruits and vegetables are good for you. Eighty-eight percent of Americans fall short of the recommended minimum five daily servings of any produce, missing out on a simple and inexpensive way to maintain their health. A month's supply of statins, the cholesterol-blocking drugs many Americans take to prevent heart disease, can cost $100. On the other hand, keeping yourself in produce, which has similar effects, will set you back only about $20.