美国国家公共电台 NPR Frozen Food Fan? As Sales Rise, Studies Show Frozen Produce Is As Healthy As Fresh（在线收听）

MARY LOUISE KELLY, HOST:

Frozen food is having a moment. After years in a slump, sales of frozen and prepared foods are on the rise. They are often cheaper than fresh and can be more convenient. As NPR's Allison Aubrey reports, another upside of frozen food may come as a surprise.

ALLISON AUBREY, BYLINE: Like a lot of us, Olivia Mitchell (ph) has had some preconceived notions about frozen food. She prefers to buy fresh produce.

OLIVIA MITCHELL: I think so. I mean, fresh and local is, you know, what they say is - tends to be healthier.

AUBREY: But with two young children and a busy schedule, she's come to appreciate the frozen food aisle.

MITCHELL: I buy frozen peas and okra.

AUBREY: With a quick zap in the microwave, you can get them from the freezer to the dinner table in a flash. And Mitchell says less goes to waste.

MITCHELL: I think frozen is great because sometimes with fresh food, it goes bad.

AUBREY: After it sits too long in the fridge. All these factors explain the renewed interest in frozen, says Phil Lempert. He's editor of supermarketguru.com. The uptick is recent, he says. But he thinks it will continue.

PHIL LEMPERT: It's affordability. It's convenience. It's not having a lot of waste. People are more concerned about waste than ever before.

AUBREY: And so what about the assumption that fresh produce is healthiest? Well, it turns out that frozen produce can pack a punch when it comes to nutrition. When you freeze fruits and vegetables, it locks in nutrients. And several studies show this helps retain high levels of vitamins. Plant scientist Hazel MacTavish-West, who works as a consultant to the food industry, says freezing is a great preservation method. Take a bag of blueberries or peas.

HAZEL MACTAVISH-WEST: So you could store them in the freezer for a year, and the nutrient level pretty much stays the same.

AUBREY: By comparison, fresh produce continues to lose nutrients due to handling and oxidation.

MACTAVISH-WEST: You could take fresh vegetables, and you put them in the fridge maybe for up to a week. They'll just continue to decline in most cases.

AUBREY: To nail down how fresh compares to frozen, food scientist Diane Barrett and a group of colleagues at UC Davis evaluated a bunch of fruits and vegetables. With funding from the Frozen Food Foundation, they measured the nutrients in samples of fresh and frozen carrots, broccoli, spinach, peas and berries.

DIANE BARRETT: Overall, the frozen was as good as fresh. And in some cases, some of the frozen fruits and vegetables were better than fresh.

AUBREY: For instance, most of the frozen produce had higher levels of vitamin E.

BARRETT: That was really the most shocking thing.

AUBREY: Barrett says frozen produce does lose some nutrients during processing when it's blanched or steamed. But she says part of the reason the nutrition holds up well in frozen fruits and vegetables has to do with how quickly they're frozen after harvest.

BARRETT: Typically the freezing facilities are very close to the place where the vegetable is grown. So within hours, that vegetable is frozen.

AUBREY: Of course fresh produce is loaded with nutrients, too. And many people are big believers in the buy-local movement. But Barrett says frozen holds its own, and it could be one more factor to help make the frozen aisle a little more attractive. Allison Aubrey, NPR News.

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