Cooking Veggies May Not Cut Nutrients
Study: Some Cooking Methods Maintain or Boost Certain Nutrients in Vegetables
Dec. 21, 2007 -- Cooking vegetables may not reduce all of the nutrients in
those veggies, according to a new Italian study.
The University of Parma's Nicoletta Pellegrini, PhD, and colleagues bought
freshly harvested carrots, zucchini, and broccoli at a local market.
In their lab, the scientists measured levels of various antioxidants in the
raw vegetables. Then they boiled, steamed, or fried the vegetables. Lastly,
they measured antioxidant levels in the cooked vegetables.
Raw vegetables were loaded with antioxidants. After cooking, their
antioxidant levels were a mixed bag.
In some cases, the veggies lost antioxidants to cooking. But not all
antioxidants decreased when cooked -- and in some cases, certain antioxidant
levels rose when cooked.
For instance, steamed broccoli contained higher levels than raw broccoli of
glucosinolate compounds, which may reduce cancer risk. And boiled carrots
contained higher levels than raw carrots of carotenoids, which give carrots
their bright orange color.
No single method of cooking stood out as being best for all
"Our results suggest that for each vegetable a preferential cooking
method could be selected to preserve or improve its nutritional qualities,"
write the researchers.
Their findings appear in the Journal of Agricultural and Food