Polyphenols are phytochemicals responsible for the astringency, bitterness, green flavours and antioxidant activities in cocoa (Theobroma cacao) beans. During rosting, the step of chocolate procesing that brings out the flavor, some of the healthful polyphenols are lost. To make chocolate more healthful and sweeter, Emmanuel Ohene Afoakwa and colleagues, University of Ghana, Legon, have experienced with cocoa pulp pre-conditioning by pod storage and roasting duration.
The researchers divided 300 pods into four groups that were either not stored, stored for three, seven, or ten days before processing. They took samples from each of the storage groups and roasted them at the same temperature for different times. The current process is to roast the beans for 10–20 minutes at 248–266 °F (120–130 °C). The team found that the seven-day storage and a slower roasting (45 minutes) at lower temperature (242 °F; 116.7 °C) resulted in the highest antioxidant activity and more polyphenols. The pulp pre-conditioning likely allowed the sweet pulp surrounding the beans inside the pod to alter the biochemical and physical constituents of the beans before the fermentation.
- Presented at the 249th National Meeting & Exposition of the American Chemical Society (ACS), Denver, CO, USA