Combine chicken broth, corn, and chicken pieces in a large saucepan. Bring mixture to a boil over medium heat, stirring occasionally. Blend cornstarch with cold water and add to soup. Continue cooking, uncoverd, for 3 minutes. Beat egg whites untill foamy; stir into soup.
Reduce heat to a simmer and cook until foamy. Ladle soup into individual bowls and garnish with parsley. Serve hot