Oil yields for Allanblackia parviflora (tallow tree) in Ghana: the effects of oil extraction methods, tree morphology and environmental characteristics

摘要

This study provided understanding of the oil yields from Allanblackia parviflora fruits in Ghana. The study sought patterns of variations in oil yield between 157 trees, 16 communities and 3 ecological zones. Ecological zone and soil properties were considered as surrogates for growing conditions associated with tree and fruit morphology. Kernel and seed oil yields were determined using the manual screw press ranged from 31.3 to 61.8% and 0.2 to 36.8%, respectively. Large variations were observed between individual trees, and significant oil yield differences were observed between the 16 communities. There were no relationships between oil yields and soil properties, even though tree-to-tree differences were observed. The farmers' estimated ages of the trees predicted kernel oil yields: very young and very old trees revealed medium and low kernel oil yields, respectively. Kernel oil yields were also seen to be influenced by ecological zone. Most of the low kernel oil yielding trees were identified in the semi deciduous forest zone (SD), and more trees in wet evergreen forest zone (W) were identified as very high kernel oil yielding trees. Trees selection for domestication can be based on tree phenotype and providing environmental conditions similar to the wet evergreen forest zone.