Scientifically and health minded chocolate and cocoa eaters take note. Processing of cocoa powder to make it less bitter removes substantial amounts of antioxidants.
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 why Mars sells their Cocoavia line of chocolates that have more retained antioxidants. But it is not clear to me how high the concentration of antioxidants is in Cocoavia versus lightly processed or even heavily processed cocoa powders.
When buying cocoa powders what we need to know is just how heavily processed they have been. The difference between 40% and 10% retention of flavanols is a factor of 4.
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.
That USDA Procyanidin Database makes for interesting reading (at least to me). Raw pinto beans are up there with unsweetened chocolate in terms of procyanidin antioxidants and you can eat a lot more pinto beans than chocolate. But cooked pinto beans have about 2 orders of magnitude less of the good stuff. Is that accurate? Blueberries and cranberries are excellent sources. Ditto hazelnuts, pecans, and pistachios. Sorghum is highly excellent. I had no idea. But that's typically cooked. Whereas you can eat the berries and nuts raw. My advice: eat the berries and nuts.
Update: Chocolate contains resveratrol.
In the study, top selling retail products from six categories were tested for the level of resveratrol and its sister compound, piceid. The six product categories included cocoa powder, baking chocolate, dark chocolate, semi-sweet baking chips, milk chocolate and chocolate syrup. Gram for gram, cocoa powder had the highest average amount of resveratrol and piceid, followed by baking chocolates, dark chocolates, semi-sweet chips, milk chocolate and then chocolate syrup. In the products studied, the level of piceid was 3 to 6 times the level of resveratrol.
When the cocoa and chocolate levels were compared to published values for a serving of red wine, roasted peanuts and peanut butter, resveratrol levels of cocoa powders, baking chocolates and dark chocolate all exceeded the levels for roasted peanuts and peanut butter per serving, but were less than California red wine.
My guess: If you want to get a regular substantial dose of resveratrol then best to take pills.
|Share |||Randall Parker, 2008 October 20 08:27 PM Aging Diet Resveratrol|