Energy Requirements in the Processing of Cocoa Beans into Powder

Abstract

This paper aims to analyse the direct energy utilization in the processing of cocoa beans into powder using energy from the national grid and diesel engine in some cocoa processing factories located in South-western Nigeria. Energy consumption in the processing of cocoa beans into powder was evaluated for the eight major unit operations that cocoa processing entails, namely: cleaning, roasting, winnowing, milling, alkalizing, pressing, butter packing and grinding/sieving. The data obtained were imputed into existing energy equation to estimate the energy requirement for each of the eight unit operations. The results show that total energy expenditure in the processing of raw cocoa bean into powder were 1.815 and 2.384 MJ/Kg using national grid (PHCN) and diesel engine, respectively. The most energy‐intensive operation identified were pressing and milling accounting for 58 % and 26.3 % of the total electrical energy expenditure. For all the unit operations involved in the processing of cocoa bean into powder, diesel engine generator consumed more energy than the PHCN sourced power. From material balance 7200 kg of cocoa beans will yield about 2825 kg of cocoa powder and 2925 kg of cocoa butter with about 20.14% weight loss in the processing line. This work provides important data for production planning, process optimization and reduction in energy costs in cocoa processing.