Chocolate Chemistry

Chocolate Post-Lab Questions - 20 points

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1. How is bittersweet chocolate different from unsweetened chocolate? Can one be substituted for the other in baking? 3 pts

Unsweetened chocolate, as its name indicates, contains absolutely no added sugar, while bittersweet chocolate has anywhere from about 10% to 50% sugar. Because of the difference in sugar content, these two types of chocolate are not interchangeable in recipes.

2. Lots of chocolate is “Dutch-processed”. What does “Dutch-processed” mean and how does it chemically change the chocolate? 2 pts

Dutch process cocoa powder is washed with a potassium carbonate solution that neutralizes cocoa's acidity to a pH of 7. Since Dutch process cocoa isn't acidic, it doesn't react with alkaline leaveners like baking soda to produce carbon dioxide. That's why recipes that use Dutch process cocoa are usually leavened by baking powder, which has a neutral pH.

3. Read this article about studies looking at the health benefits of eating chocolate from “NIH News in Health” at http://newsinhealth.nih.gov/issue/Aug2011/Feature1. Write a 1-2 paragraph summary of the article while answering the following questions. 6 pts

* How strong is the evidence that eating chocolate has a beneficial effect on any aspect of the average American’s health?

* Flavanols are believed to be “responsible for the beneficial aspects” of eating chocolate. How can you determine the flavanol content for a given chocolate?

* Compare the health effects of the three types of chocolate – dark, milk and white chocolate.

* What are the detrimental effects of eating chocolate?

The NIH News shows that the evidence of eating chocolate has a beneficial effect on any aspect of the average American’s health is very weak. Scientists believe that flavanols might be the reason why chocolate is healthy, but since many companies remove the Flavanols from chocolate because of its bitter taste,...