Post-harvest handling of kolanut: Cola acuminate and Cola nitida Schott & Endl. using three storage structures in Lagos, Nigeria

Two kolanut varieties, Cola acuminate, and Cola nitida, were preserved in three (3) various kinds of special shape set-up structures over a length of eleven (11) weeks, and their exceptional qualities were evaluated over time. Rafia Baskets, Jute Bags, and Paper cartons were used as outside structures. To minimize moisture loss in storage, three other materials were used to line each outside structure: Gbago leaves which were in direct contact with the Kolanuts, followed by brown paper, and all wrapped in transparent polythene. The study was carried out at the Entomological Laboratory, Lagos Zonal Office of Nigeria Stored Products Research Institute, Nigeria. Mean values of temperature and relative humidity obtained from the data logger during the study are 27–28oC and 81-85%, respectively. Parameters used to evaluate quality during the study were sprouting, colour changes, rot, weight loss, mould formation, rusty-brown spots, and weevil damage. At a 95% significance level, rot and weight loss were found to be significantly greater in Cola nitida than in Cola acuminata, while sprouting was significantly greater in Cola acuminata. For both kolanut varieties, quality during storage varied significantly with storage structure, C. acuminata stored better than C. nitida. For both kolanut varieties, Jute Bags recorded the highest reduction in quality based on the quality parameters measured.