UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
How do you make chocolate?
Question Date: 2013-02-27
Answer 1:

Chocolate is an amazing food, isn’t it? It comes from the Cacao tree, which is native to South America, but is mostly grown in Africa now.

The fruit of the tree is interesting because it grows off the trunk instead of at the ends of branches. It is about 15 cm (6 inches) long and is sort of football-shaped. We don’t eat the fruit itself, we eat the beans (also known as seeds) inside. About 2,000 years ago, the Aztec people may have been eating the fruit of the cacao tree. They didn’t try eating the seeds until much later, but it’s hard to know exactly when. The first chocolate was probably made in the 1500s in South America. Cacao seeds were so valuable that they were used as money and only the very rich actually ate them.

Farmers grow cacao trees in forests instead of orchards. The tiny fly-like animal (a midge) that pollinates the cacao likes the cool, moist forest floor. Without pollinators, the cacao flowers would not grow into cacao fruit.

When growers harvest the fruit twice a year, they cut it open and let the seeds ferment in the sun, along with the fruit. The seeds have a soft, slimy covering and the fermentation by wild bacteria removes the coating. The bacteria also cause chemical changes in the seeds, which will improve the flavor and aroma. Farmers dry the bean in the sun or in drying ovens, then ship the beans to factories all over the world.

The factories clean and roast the beans, then crack off the hulls, leaving the inner bean. They grind this inner part to make a paste. It can be dried into blocks or dried and then ground into baking cocoa. Better yet, it can be mixed with sugar to make dark chocolate for candy. You can probably guess what else they add to make milk chocolate.

As you can see, this is a very complicated process that relies on a forest community to successfully grow trees and a bacterial community to ferment the seeds. No one has ever been able to make chocolate in a lab without the seeds and the bacteria.

chocolate because it allows them to make a living while protecting rainforest species. Why would those species do better in a forest than in an open orchard?

Thanks for asking. I have to go eat some chocolate now.

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use