Antioxidants from Eggs
Jianping Wu, Andreas Schieber and graduate students Chamila Nimalaratne and Daise Lopes-Lutz of the U of A Department of Agricultural Food and Nutritional Science examined egg yolks produced by hens fed typical diets of either primarily wheat or corn.
They found the yolks contained two amino acids, tryptophan and tyrosine, which have high antioxidant properties.
After analyzing the properties, the researchers determined that two egg yolks in their raw state have almost twice as many antioxidant properties as an apple and about the same as half a serving (25g) of cranberries.
However, when the eggs were fried or boiled, antioxidant properties were reduced by about half, and a little more than half if the eggs were cooked in a microwave.
"It's a big reduction but it still leaves eggs equal to apples in their antioxidant value," said Wu.
The discovery of these two amino acids, while important, may only signify the beginning of finding antioxidant properties in egg yolks, said Wu, an associate professor of agricultural, food and nutritional science.
The study was published in the peer-reviewed journal Food Chemistry.
From the July 7, 2011, Prepared Foods' Daily News.