The antioxidant content of chocolate, particularly the levels of flavan-3-ol, is the most important factor in delivering a potentially beneficial dose, report researchers, but the formulation does play a part.
“Due to the fact that the net absorption and resulting circulating levels of flavan-3-ols are regarded to be generally low, designing matrices to optimize the flavan-3-ol bioavailability resulting from cocoa consumption could prove to be an important strategy for maximizing the in vivo health benefits from cocoa products,” explained the researchers in the Journal of Agricultural and Food Chemistry.
Researchers from Purdue University, collaborating with scientists from Research, Development, and Quality at Kraft Foods, recruited six people to consume a variety of chocolate products, and found the highest blood levels of flavon-3-ol were obtained following consumption of a beverage and chocolate in a high sugar matrix.
“Therefore, it seems plausible that beverage and/or high sucrose matrices could be designed to facilitate rapid appearance of flavan-3-ols in blood at higher maximal concentrations,” wrote the researchers, led by Purdue’s Mario Ferruzzi.
“Confection chocolate formulations could be designed to maintain lower flavan-3-ol concentrations for extended periods of time,” they added.
Antioxidants in chocolate and beyond
The health benefits of antioxidant-rich chocolate have received much recognition in recent years, with positive findings from a number of studies impacting on consumer awareness. Chocolate manufacturers are using high cocoa content (over 70 per cent) as a means of differentiation, and cocoa has also received attention for its potential in functional food applications.
Despite higher flavon-3-ol levels being measured following consumption of a high sugar matrix, the sugar content of such formulators would not be readily accepted by health-conscious consumers, suggesting that the beverage formulations may offer the most potential.
The Purdue-Kraft researchers measured the bioavailability of epicatechin (EC) from various cocoa matrices, including solid confections such as dark chocolate, high sugar and high milk protein chocolate, and chocolate beverages including a sugar-milk protein, and a non-nutritive sweetener (sucralose) milk protein drink. All products were formulated with a 36mg catechin plus epicatechin per serving, based on the raw materials.
Both humans (six subjects) and in vitro studies were performed and the researchers found that, the greatest increases in blood levels of EC were observed following consumption of the beverages. The beverages also produced the quickest increases in blood levels, albeit not statistically different to the other products.
Regarding the confectionery products, matrices containing higher levels of sucrose appeared to lead to quicker and higher EC levels in the blood, compared to lower sucrose and milk formulations, said the researchers.
“These data suggest that bioavailability of cocoa flavan-3-ols is likely similar from typical commercial cocoa based foods and beverages, but that the physical form and sucrose content may influence [the speed of absorption] and [the maximum concentration achieved in the blood],” concluded the researchers.
Proof in the pudding
A recently study by the Hershey Company, in collaboration with scientists from Brunswick Laboratories, found that maintenance of cocoa’s heart healthy compounds in a finished product like chocolate cake depends on the presence of other ingredients, particularly the leavening agents.
Their results, published in the Journal of Food Science, found that using baking powder rather than baking soda in a chocolate cake mix preserves the product’s antioxidant activity and flavanol content.
Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, 25 September 2009, doi: 10.1021/jf902919k
“Influence of Chocolate Matrix Composition on Cocoa Flavan-3-ol Bioaccessibility In Vitro and Bioavailability in Humans”
Authors: Andrew P. Neilson, J.C. George, E.M. Janle, R.D. Mattes, R. Rudolph, N.V. Matusheski, Mario G. Ferruzzi