Health & nutrition
It's a common question, which is better? Frozen or fresh? What about when it comes to meat?
It depends, of course. The experts cite many, many variables. But perhaps we're asking the wrong questions.
Most frozen produce is picked at peak season and then immediately frozen to retain nutrients and freshness. Fresh produce from faraway places, on the other hand, loses some of its nutrient value while traveling and then sitting on a shelf for days or longer. But the amount of nutrient loss varies greatly depending on the type of produce, says Jeff Blumberg, professor of nutrition science and policy at Tufts University.
"If you are looking at something like fresh spinach, you are losing up to half the folates after about eight days," Blumberg says.
In general green, leafy vegetables are the most delicate and susceptible to nutrition loss, while vegetables and fruit with a skin or shell (think oranges or squash) are more robust and stay nutritionally intact longer, he says.
That being said, even the green leafy varieties don't lose nutrients across the board, says Kristen Ciuba, a nutritionist.
"You are not going to lose the fiber or the minerals," Ciuba says.
And even when nutrients are lost, Blumberg adds, some produce, such as spinach, is so rich in folates that "you can afford to lose some of it." Spinach is so nutrition-dense that it's good for you either way you eat it, he says.
And this is generally the story on produce. Get your five to nine servings a day in whatever form you can.
Just make sure, says Ciuba, that the frozen variety doesn't include added salt (vegetables) or added sugar (fruit and berries).
Another thing to keep in mind is to buy whole frozen or fresh fruits and vegetables whenever possible. "Avoid buying chopped, peeled and crushed produce if at all possible," Blumberg says. "Because whenever you accelerate the degradation process, you lose nutrients."
The way produce is prepared actually is more important for nutrition retention than picking the absolute freshest of fresh spinach, for example.
"If you were to boil spinach you would lose much more folate than if you had it sitting in the fridge a few days," Blumberg says, adding that lightly steamed or raw is preferable.
Other things to consider are the economics of produce (frozen often is cheaper than fresh) as well as taste and texture. Some produce just doesn't fare very well when frozen.
Think frozen asparagus. Mushy, right?
"They just don't taste good when their cellular structures are altered," Blumberg says.
Both Ciuba and Blumberg emphasize that the main message, though, should be to eat more produce, whether fresh or frozen.
"Don't over-worry this frozen/fresh thing. The most important thing here is to eat plant food in whatever form it may be, up to nine servings a day," Blumberg says. "Most people don't eat enough produce, and not being able to buy local produce should not be an excuse to eat even less."
Says Ciuba: "You're missing the boat if you won't eat anything but organic and local. Are you going to replace an apple with an organic cracker?"
Fish, meat and poultry
Although they're not seasonal, like veggies and fruit, meat and fish are part of the fresh-vs.-frozen debate, too. And the answers here echo those for produce.
"Frozen fish is not inferior, nutritionally speaking," says Aliza Green, a Philadelphia-based chef and author of "The Fishmonger's Apprentice: The Expert's Guide to Selecting, Preparing, and Cooking a World of Seafood, Taught by the Masters."
"If you had asked me in the '70s and '80s, when I first started out as a chef, I would have said 'only buy fresh fish,' " she says. "But I have really changed my mind. The freezing technology is so much better now."
These days, she says, the freshly caught fish is flash-frozen aboard the fishing boat, keeping it nutritionally intact and "fresh" longer.
It should also be noted that all wild-caught fish - by law - has to be frozen in order to kill parasites, she says. In other words, unless you're catching it yourself, there is no such thing as fresh, wild-caught fish, she says.
Farm-raised fish, on the other hand, often is shipped and sold to consumers without being frozen first.
So, it comes down to what looks good at the store.
"Fresh fish should not smell fishy - at all," Ciuba says. "And if it's frozen, look for freezer burn or crystals." If you see them it means the fish has been thawed and refrozen, which affects quality.
Overall, in terms of flavor and texture, fresh, farm-raised fish often is preferable, Green says. But if you decide to go with frozen fish just know, she says, that some fish types do better in the freezer than others. Lean, white varieties such as cod tend to become dry when frozen, but the fattier types, such as tuna and salmon, should be fine even when frozen.
The same nutritional rules hold true for meat and poultry, according to the Agriculture Department. "Freezing meat and poultry does not affect the nutritional value," says CiCi Williamson, a food safety expert with the USDA meat and poultry hotline. "It should be fine for a month or longer," she says. But keep an eye on the fat content - the fattier the meat, the better it will freeze, just like fish. Look for bigger cuts and vacuum-sealed packaging, and make sure to keep the freezer as cold as possible. For a list of freezer storage times and other information on freezing foods, the USDA's Food Safety and Inspection Service has a Freezing and Food Safety fact sheet at www.fsis.usda.gov.
Important aspects of preparing frozen meats and fish, Green says, are to make sure they thaw slowly (in the fridge) and aren't overcooked.
With fish, prepare with olive oil, lemon and maybe some parsley and perhaps top with fresh salsa - all healthy choices.
"Just don't over-think the frozen versus fresh," Green says. "The biggest problem is that people don't eat enough fish - not that they eat the 'wrong' fish."
In other words, "fresh or frozen?" is the wrong question. Instead, the more important question is: Are you getting enough produce and lean proteins?
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