It’s one of the most festive weeks of the year! For many people, this time of year involves some combination of twinkling lights, meetings with friends and family, maybe a goofy sweater or two, and of course, some CHOCOLATE. The holidays tend to bring an abundance of good food, but even with all of the figgy puddings and sugar plums to choose from, doesn’t it seem like there is always some kind of chocolate within reach somewhere during this particular week of the year? Why is chocolate the treat much of the world seems to crave, in good times and bad? From a biological point of view, it may have something to do with the fact that the chocolate we love is derived from a plant that has powerful psychoactive properties, Theobroma Cacao.
When Montezuma met the Spanish conquistadores in 1519, he intended to overwhelm them with a lavish display of royal hospitality. To impress, the emperor of six million people brought out fifty golden jugs of one of his most potent weapons – chocolate. However, what he served to the awed Spanish was not at all like the sweet chocolate we enjoy today. The cacao plant is native to the Amazon region, and Montezuma was serving up an elite tradition of chocolate that had begun 3,000 years before the Spanish arrival. The Spanish experienced a drink made of the beans of the cacao pod, ground and mixed with water, vanilla, chile, and cornmeal, which had been poured back and forth at a height to create an enticing, bitter, melt-in-your-mouth froth. In an instant, the global obsession with chocolate was born.
Chocolate can now be found anywhere in the world, and it’s easy to forget that under the bright wrappers and diverse flavors, chocolate comes from a plant with a very powerful chemical profile. The cacao tree and its precious seedpods only grow in equatorial regions of the world, and produce a bean that is much more than just tasty. Cacao beans are psychoactive, with multiple compounds capable of stimulating the production of neurotransmitters in the brain. Through their bitter and frothy beverage, Mesoamericans were the first to enjoy the stimulating effects of Theobromine, a chemical in cacao that is very similar to caffeine. Theobromine increases blood flow, inducing a feeling of mental alertness, vigor, and overall well-being. On top of this dynamic duo, cacao also has Tryptophan and Phenylethylamine, among many other compounds. Tryptophan assists in the creation of the “feel-good” neurotransmitter Serotonin. Phenylethylamine assists with the creation of another happiness-inducing neurotransmitter, Dopamine. These delightful neurotransmitters, plus a surprising number of antioxidants and anti-inflammatory compounds, can help explain humankind’s passionate three-thousand-year love affair with chocolate.
The cacao beans that furnish this phytochemical feast are actually quite challenging to grow. Theobroma Cacao plants need just the right conditions and lots of care to fight the diseases and pests that typically attack them, not to mention just the right insects to fertilize them. There are three main varieties of cacao bean available today, and within each variety there are several, often genetically different, hybrid strains. Relatively hardy Forestera beans make up 85 percent of the world’s chocolate. Most prized, rare, and delicate are Criollo beans, which provide 3% of the world’s chocolate. The hybrid of Forestera and Criollo is known as Trinitario, was created in the 18th century when a hurricane nearly caused the Criollo variety to go extinct. Although Criollo plants are not productive on a scale that can meet global demand, they produce flavors and aromas that are more complex and rich. Much like wine, Criollo can be described as having notes of fruit, tobacco, or caramel. Criollo was the preferred variety of the Aztec and Maya, and most likely the one that the Spanish enjoyed as part of Montezuma’s hospitality.
Go to the supermarket today, and in the candy aisle you will see an array of chocolate worthy of an Aztec Emperor. An Aztec Emperor would surely recoil at the sweet, milky flavors of chocolate today, but that is the beauty in the biology of chocolate. Cacao’s pleasing array of phytochemicals and rich flavors practically guarantee an enjoyable experience. Whether taken bitter by an emperor or sweet on a holiday visit, on the molecular level, chocolate is sure to satisfy your brain and not just your sweet tooth.
Sources and Further Reading:
An Introduction to the Science of Chocolate: https://www.youtube.com/watch?v=bt7tzEzEg5o
A General history of Chocolate: https://www.youtube.com/watch?v=ibjUpk9Iagk
Africa and the Global Cocoa Trade: https://www.youtube.com/watch?v=G4c7l_CVwFc
A small farmer’s up-close look at harvesting, fermenting and roasting Cacao beans: https://www.youtube.com/watch?v=V-4FsJ6-bzc
The Neurochemistry of Chocolate: https://www.scilearn.com/why-your-brain-loves-chocolate/
Scientific Paper on the Health Benefits of Chocolate: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3575938/