Estimating Energy Requirements in the Processing of African Locust Beans (Parkia biglobosa) into Condiment

Food industry requires energy for many processes. Hence, the knowledge about energy use in agriculture and the food system is essential in developing a sustainable food production system especially in a developing nation like Nigeria. A comparative study of the energy requirements for processing African locust beans into condiment (iru) using the traditional and a small- scale mechanized processing methods were carried out. For both processes, quantitative data on the operating conditions for each unit operation were measured during processing of raw African locust bean to iru (the condiment). Standard equations were used to estimate energy demand. Mean total energy for processing 24 kg of raw locust bean seed into condiment (iru) using traditional method was estimated to be 1435.75± 34.34 MJ with energy intensity of 59.82 ± 1.4 MJ/kg. Estimated total energy required for converting 24 kg of raw locust bean seed into condiment using semi-mechanized method was 1621.55 ± 46.98 MJ and intensity was 67.56 ± 1.3 MJ/kg. Thermal ((1383.24 MJ ≍ 96.30%) and manual (52.49 MJ ≍ 3.66%) energy were the sources of energy used in traditional method. Energy sources of semi-mechanized were thermal (1563.52MJ ≍ 96.45%), manual (29.65 MJ ≍ 1.83%) and electricity (28.38 MJ ≍ 1.75%). In both processes, the first boiling operation was identified as the most energy intensive operation while hand picking and fermentation were identified as the least energy consuming operations in traditional and semi-mechanized methods. Input of machines in the semi-mechanized process represents a small fraction of the total energy consumed (1.96%), but the effect was significant at p < 0.05.