Digitalization of Management of Cocoa Bean Fermentation Process to Guarantee Beans Quality

Abstract

Cocoa bean fermentation is a critical post-harvest operation that influences bean quality and suitability for chocolate processing. This study examined the digitalisation of cocoa bean fermentation management using an instrumented cylindrical fermenter designed to support monitoring and controlled turning. Ripe cocoa pods obtained from Côte d’Ivoire were fermented in cylindrical fermenters made of plastic and wood. Fermentation behaviour was assessed through temperature monitoring, microbial population analysis and pH measurement of bean components. Temperature probes inserted at different heights in the fermenting mass recorded thermal evolution, while yeasts, lactic acid bacteria, acetic acid bacteria, Bacillus and moulds were enumerated using dilution and culture methods. The pH of whole beans, kernels and pulp-shell fractions was also monitored. The cylindrical fermenter retained fermentation heat and showed relatively small temperature differences between turning operations. Internal temperatures increased during fermentation and reached values consistent with active fermentation. Microbial succession followed the expected trend, with yeasts and lactic acid bacteria appearing early, followed by acetic acid bacteria and Bacillus during later stages. The study also presents an electronic control approach using a microcontroller, relays, a motorised turning mechanism, temperature sensors and a mobile application interface for remote observation and turning control. The results indicate that temperature is a suitable physical parameter for digital monitoring of cocoa fermentation. The cylindrical fermenter and dynamic turning method produced at least 80% brown beans. The proposed system may reduce manual workload and support more consistent process management, although further field validation remains necessary.