Cacao would never obtain its rich flavor profile without a traditional food processing technique: fermentation.
“I feel like fermentation adds about three-quarters of the flavor to the finished chocolate. I think it is the most important step in the entire tree-to-bar process for the flavor of the chocolate, and the chocolate makers have been taking too much credit for the flavor of their chocolate,” says Nat Bletter, PhD and founder of Madre Chocolate.
Chocolate makers “can definitely take a great grown and fermented cacao and make it shine, but it’s really hard to take a badly grown and fermented cacao and make a good tasting chocolate and that’s why so much of the world’s chocolate is loaded with milk and sugar to try to cover up some of the bad fermentation flavors.”
Bletter joined Max Wax (vice president of Rizek Cacao) and Dan O’Doherty (principal of Cacao Services) in sharing their expertise during a joint webinar, The Fermentation-Flavor Connection in Chocolate., co-hosted byThe Fine Chocolate Industry Association and The Fermentation Association..
The three speakers work in different size chocolate operations. Madre Chocolate is a small-scale chocolate making company in Honolulu that uses cacao from small Hawaiian farmers; Rizek Cacao is a producer and exporter of cacao and cacao products based in the Dominican Republic; and Cacao Services (also in Honolulu) s an agricultural and scientific consulting company that specifically focuses on cacao production systems.
Complex fermentation
Cacao fermentation is among the most complex of food ferments because it utilizes three families of microbes and 5-10 species in each. “It is a little bit hard to control since it’s not just one single species of microbes that you’re trying to support a good ecosystem,” Bletter adds.
Wax attributes less of chocolate’s flavor to fermentation. He says there are flavors produced by the metabolism of the plant itself, “so genetics is probably No. 1, then comes the terroir that comes with fermentation. We shouldn’t be dogmatic on fermentation but on the contrary open to this fantastic dialogue between wisdom and science.”
A chocolate maker is responsible for studying the effects of yeasts on their cacao ferment, Wax adds. They should ask: How does the naturally occurring yeast change flavor? What’s the metabolism rate? Is there a possibility of naturally inoculating the cacao for a different flavor?
“It is absolutely true that you should not inoculate something using either commercial yeast or yeast from grapes or other types of culture, or even from different environments,” Wax says. “But it is also true that the variety of yeast that is naturally occurring, not all of them give the same taste profile. … Nobody wants the same flavor and the same cacao forever, just as we don’t want the same wine or the same cheese or the same yogurt or the same beer.”
Rizek Cacao employs 32 varieties of yeast in their chocolate.
Sensory Cues
O’Doherty, who works with cacao farmers, says it’s possible to ferment cacao without any kind of quantitative measuring devices.
“If you’re an experienced fermenter and you really know what you’re looking at, you use all your senses,” O’Doherty says. A fermented cacao bean will be plump and juicy; the color will be reddish-brown (a pale bean is under-fermented) and the bean’s scent will change depending on the stage of the fermentation process.
“If I only had one sense to go on for cacao fermentation, I think it really would be aroma,” O’Doherty continues. The scent sequence will begin as fresh and fruity, transition to a strong yeast fragrance, next to wine , then to ethanol and, finally, the sharp vinegar scent will fade to a fruity vinegar.
One of the topics mostly frequently raised by cacao producers, says O’Doherty,is how to modernize their operations. He points out that most cacao farmers still ferment using boxes and heaps.
“In general, cacao cultivation and processing is centuries behind,” he says. Most cacao farms are run by small shareholders who don’t have the money for barrels or stainless steel equipment. “Sophisticated fermentation vessels are not really an option for consideration. Truth be told, well executed, both heaps and wooden box fermentations can produce some absolutely fantastic cacao.”
O’Doherty concludes: “The larger question about commodity cacao and the incentives or lack thereof is the reason that I have a job helping farmers with fermentation. Although there may be traditions, there’s no feedback mechanism. There is no incentive for good quality and, typically, there’s really not a penalty for bad quality, unless it is actually decomposing…a lot of the work I do is linking these producers that I assist with their harvest and process to chocolate makers that will pay double or triple the typical commodity price. I still don’t think that’s enough but it’s moving the needle in the right direction.”