New study re-emphasizes natural cocoa powder has high antioxidant content

Study also shows that Dutched cocoas retain significant levels of antioxidants

09 oct 2008--Over the past ten years, dark chocolate and cocoa have become recognized through numerous studies for flavanol antioxidant benefits. In a study published this month in the Journal of Agricultural and Food Chemistry, scientists from The Hershey Company and Brunswick Laboratories of Norton, MA report on the levels of antioxidants in selected cocoa powders and the effect of processing on the antioxidant levels. The study, which analyzed Hershey's Natural Cocoa Powder and nineteen other cocoa powders, reported that natural cocoa powders have the highest levels of antioxidants. Natural cocoa powders contained an average of 34.6 mg of flavanols per gram of cocoa powder, or about 3.5% of total flavanols by weight. This places cocoa powder among the foods highest in these types of antioxidants.
The study went on to look at a variety of Dutched (alkaline processed) cocoa powders, which are commonly used by the food industry. New findings showed that the Dutched cocoa powders, especially the light- and medium-Dutched cocoa powders, retained significant amounts of cocoa flavanol antioxidants. In fact, despite the losses created by light to medium Dutch processing, these cocoa powders still were in the top 10% of flavanol-containing foods when results were compared to foods listed in the USDA Procyanidin Database.
"This is an important finding for people who like all things chocolate." said Ken Miller, the lead author of the paper. "Because cocoa powder is one of the richest sources of flavanol antioxidants to start with, even lightly- or medium-Dutched processed cocoa powders still retain significant levels of the beneficial antioxidants."
Dutching, or alkali treatment, of cocoa is a 180-year-old process used to lower the bitterness and darken the color of cocoa powder. Dutched cocoas are commonly used in beverages such as chocolate milk and hot cocoa mixes, in cakes and cookies, and in a limited number of confections. In the United States, the presence of Dutched cocoa or Dutched chocolate is indicated by looking for the terms "dutched" or "processed with alkali" on the ingredients label.
In this study, the degree of cocoa alkalization caused a progressive, but not complete loss, of flavanol antioxidants, with about 40% retained in lightly dutched cocoas, 25% retained in medium dutched cocoas, and 10% retained in heavily dutched cocoas.