Researchers Dig Into Cocoa’s Past to Grow a Better Future

Cocoa is a treat that has been enjoyed for thousands of years and by people from all over the world. People love the rich, sweet, creamy taste of chocolate. However, it’s more than a tasty delight. According to the National Confectioners Association, up to 50 million individuals rely on the cocoa industry for their livelihood.

Chocolate is produced from the cocoa bean, the fruit of the Theobroma cacao tree, which translates to “food of the gods.” Now, scientists are using genetic research to trace the cacao tree’s ancient evolutionary origins, according to Earth.com. They hope that through exploring the tree’s ancient evolutionary roots, they will find the means to ensure its prosperous future.

Cacao Challenges
Despite the size of the cocoa industry, the trees that are a source of chocolate are delicate. Cacao trees only begin producing cocoa beans at four to five years old and each tree will produce approximately 2,500 beans over the course of its lifetime. Around 400 beans are needed to produce just a pound of chocolate. Additionally, cacao trees’ frailty results in around 30 percent of the crop, on average, being lost per year.

Climate change threatens these already fragile trees, NPR reports. Sweltering heat makes it difficult for the trees to grow, whereas unusually copious amounts of rainfall lead to fungal infections.

Recently, nearly half of the cocoa yield in some areas was wiped out by a devastating virus. CSSVD, the cacao swollen shoot virus disease, spread by mealybugs that prey on the trees’ buds, leaves, and flowers, has taken its toll. This comes as Ghana has lost over 254 million chocolate-producing trees in recent years.

Looking to the Past
According to a study published in PLOS One, the cacao species has undergone genetic diversification over millions of years, with divergence occurring approximately 7.55 million years ago. The study emphasizes genetic variability in cacao, which has developed over time, suggesting potential for ongoing genetic diversification.

Phys.org shares researchers focused on fine aroma cacao, a unique variety of cacao with a distinctive flavor profile. Fine aroma cacao, which is estimated to have likely diverged evolutionarily during the Pleistocene (0.31 to 1.82 million years ago), doesn’t fit neatly into the most common classifications of cacao tree varieties. 

After taking seven samples from different fine aroma cacao genotypes grown in North Peru, researchers uncovered three distinct genetic groups. The groups were linked to different cacao varieties: one aligned with Trinitario and Criollo, another with Forastero from the Lower Amazon, and a third with the National and Curaray groups. They also found that there was a high level of genetic variation in the ycf1 gene, in particular, making it a good candidate for studying cacao’s evolutionary history and its potential for future genetic variation.

Through studying cacao trees’ genetic history, Earth explains, researchers hope to help growers breed and select cacao varieties that are more resilient or disease resistant, as well as those that are tastier and more productive.

Science and Tradition
Growing cacao trees was historically done by local growers in Latin America, Africa, and Asia, many of whom have been cultivating their crops for generations and have developed significant local expertise and the ability to observe small differences among trees.

This study, and others like it, open the door for traditional growers to collaborate with researchers, combining traditional know-how with lab findings to benefit growers and chocolate enthusiasts. Knowledge from the past and science may just save the future of this tasty treat.