Spring is here and symbols of new life abound. If Cadbury Cream Eggs (yes, gross, but I love them anyway) and Mini Eggs on drugstore shelves have you, too, thinking about chocolate, check out this piece in the Washington Post on the history and chemistry of the “feel-good” components of the stuff, including “the world’s most widely consumed psychoactive drug,” caffeine.
Chemist Simon Cotton, PhD, writes:
Another chocolate molecule believed to be important was discovered less than 20 years ago: anandamide. This binds to receptors in the brain known as cannabinoid receptors. These receptors were originally found to be sensitive to the most important psychoactive molecule in cannabis, Δ9-THC. Likewise, anandamide and similar molecules found in chocolate are also thought to affect mood.
Phenylethylamine, another family of chemicals, is found in chocolate in very small amounts. It is a naturally occurring substance with a structure that is closely related to synthetic amphetamines, which of course, are also stimulants. It is often said that our brain produces phenylethylamine when we fall in love. It acts by producing endorphins, the brain’s natural “feel-good” molecules. The bad news, however, is that eating chocolate is probably not the best way of getting our hands on phenylethylamine as enzymes in our liver degrade it before it can reach the brain.
There are other molecules in chocolate – especially in dark chocolate – such as flavonoids, which some scientists think may help improve cardiovascular health. But chocolate manufacturers have been known to remove bitter flavanols from dark chocolate.
One last feel-good factor, which isn’t a molecule: the melt-in-your mouth sensation. The fatty triglycerides in cocoa butter can stack together in six different ways, each resulting in a different melting point. Only one of these forms has the right melting point of about 34 degrees, so that it “melts in your mouth, not in your hand.” Getting the chocolate to crystallize to give this form is the product of very careful chocolate engineering.
I’m curious to know what kinds of chemicals give the sugary “whites” and “yolks” of the cream eggs their appeal, though maybe it’s better kept a foil-wrapped secret.
Previously: When caffeine dependence affects quality of life, Do you (heart) chocolate? Evaluating the cocoa “prescription” for cardiac health and Mapping the DNA of wild strawberries and fine chocolate
Photo by Joel Kramer