Advice from Livestrong
Don’t feel guilty about eating frozen fruit or veg
A recent email from Livestrong, the giant US cancer charity, removed the guilt from my shopping. They say “produce selected for freezing is harvested when it’s ripe, rather than harvested early and allowed to ripen during transport to the market” (as is so much of our so-called ‘fresh’ fruit and veg).
When ripe, vegetables and fruits provide the most nutrition, according to Dr. Gene Lester of the USDA Agricultural Research Center. “Shortly after being picked, fruits and vegetables start to lose moisture, become susceptible to spoilage and decline in nutrient value. The “fresh” produce you get at a grocery store was likely picked or pulled from the ground several days, or even weeks, ago. Store it in your fridge for another few days, and you’ve got vegetables and fruits that have a lot of lost nutrients”.
And there was me, thinking frozen meant second-best!
What happens during freezing? For the most part, the majority of a vegetable’s original nutritional value remains intact during the freezing process. Certain vitamins, though, will be negatively affected by the blanching process, which is the first step of freezing most vegetables. Manufacturers put cut-up vegetables in hot water to seal in their colour and kill harmful bacteria. Vitamins C and B do break down when exposed to this heat, so frozen vegetables are not ideal sources of these water-soluble nutrients.
Our ancestors did know best, shopping daily. Today, our habit of buying in bulk and keeping fruit and veg for longer can also cause vitamin C to degrade, though, so eat fresh produce quickly after purchase to get the most C.
Certain antioxidants may also be affected by freezing — but not in all vegetables. Fresh green beans, for example, have more beta-carotene than frozen, but frozen peas have more beta-carotene than fresh varieties. But eat frozen produce within a year — after that, vitamins and other nutrients start to degrade rapidly.
Where it’s equal Fruit is not typically blanched before being frozen, so fresh and frozen varieties are usually equally healthy. Both fresh and frozen blueberries, for example, have nearly equal health benefits. Some fruit, such as peaches, must be peeled before being frozen which may lower the fibre and phytonutrient content.
Choose carefully Frozen fruit sometimes contains added sugar, which means it won’t be as healthy as fresh. Some frozen vegetables, particularly those with sauces, also contain unhealthy additions such as sodium, fat and preservatives. Avoid boiling fresh or frozen produce, which further reduces the nutrient value of these foods; choose steaming instead.
When you opt for frozen, cook it straight from the freezer. A study published in a 2000 edition of “Die Nahrung” found that thawing vegetables, particularly spinach, okra and green beans, before cooking led to greater vitamin C loss. Steaming frozen vegetables in a small amount of water in a stainless steel pan leads to the greatest preservation of vitamin C.
If you think about it, frozen can make a lot of sense. How often do you buy ‘ripen at home’, and find the fruit has gone off quickly? Is it me, or don’t those green bananas, when ripened, taste like they used to?
And it can be very convenient when you don’t have time to shop, to delve into the deep freeze to pick out your ‘five a day’.