Chemistry and Materials Research www.iiste.org ISSN 2224- 3224 (Print) ISSN 2225- 0956 (Online) Vol.6 No.8, 2014 16 Studies on Some Physical Properties of Dikanut Seeds Oladimeji Olusegun 1* , Idowu-Adebayo Folake 1 and Oladokun S. Olanrewaju 2 1 Department of Food science and Technology, Faculty of Agriculture, Federal University Oye, P.M.B 373 Oye- Ekiti, Ekiti state, Nigeria. 2 School of Ocean Science and Engineering, University of Malaysia, Terengganu, Malaysia. *E-mail and Telephone number of the corresponding author: segundimeji@yahoo.com +234-803-3932642 Abstract The physical properties of dikanut seeds sold in Nigerian markets were determined. The dried seeds were evaluated for the principal dimensions, weight, volume, true density, bulk density, and porosity, angle of repose, static coefficient of friction and specific heat capacity. The average three principal dimensions were 2.375, 1.592 and 0.778cm. The seeds had an average weight of 1.904g, volume of 2.38cm 3 , density of 0.832g/cm 3 , bulk density of 0.475g/cm 3 , porosity of 43%, and surface area of 3.468cm 2 . Angle of repose and coefficient of friction varied quadratically with moisture content. The specific heat capacity of dikanuts was measured at four moisture contents and eight temperatures. The specific heat of dikanut varied from 1.9333J/g˚C to 6.075J/g˚C for moisture contents between 3% and 30% and those that were used to model multiple simple regression equations expressing specific heat as a function of moisture content. Key words: Dikanut, seed, dimension, specific heat capacity 1. Introduction Dikanut is the seed obtained from the fleshy fruit of Irvingia Gabonesis and is locally known as ‘apon’ in Yoruba land (Adeboye and Bello, 1998). The freshly harvested seeds are dried and sold openly in most Nigerian markets. The dried seeds are comminuted and used in the formulation of recipe for ‘ogbono’ soup in the southern part of Nigeria (Oguntona et al., 1999). Though dikanut is readily available in the market, its demand is always high. This has however, resulted to high selling price of dikanut (Anegbeh et al., 1996). As a result of high nutritional and economic value of dikanut (Ejiofor, 1994) coupled with a bid to bring about reduction in the market price, there are efforts to increase its production through intensive cultivation (Adeboye, 1997). Since the physical properties of dikanut seed are the prerequisites for the design of equipment for handling, dehulling and other processes, it is essential to determine these properties. The objective of this study was to determine some of the physical properties of dikanut seed at safe storage moisture content, namely: sphericity dimensions, volume, surface area, true and bulk density, porosity, static coefficient of friction against different materials, angle of repose, specific heat capacity. 2. Materials and methods A batch of 25kg of dikanut was obtained from several sources and thoroughly mixed together. All the samples were mixtures of different varieties. Manual sorting was done to remove the broken ones; the seeds were screened and air-blown to free them from any adhering particles. The batch was sun-dried to equilibrate the moisture content. The seeds were packed in double-layered low-density polyethylene bags and stored at 4˚C for 7days before starting the experiment. For each test, the required quantity of seed was taken out and allowed to warm up for about 2hours. About 10g of the samples was placed in a hot air oven at 100˚C for 36 hours (Oje and Ugbor, 1991) and then cooled by placing in a desiccator, weighed and the moisture content of the seed calculated. 2.1 Seed Dimensions One hundred seeds were randomly selected from 25kg sample. Measurements were made of the seed dimension on three mutually perpendicular axes, namely: major, intermediate and minor diameters. These dimensions were measured with a micrometer (reading up to 0.01mm) 2.2 Mass, Volume, Surface Area and Sphericity To determine the sphericity, each seed was placed in its natural resting position on a sheet of graph paper. A sharp thin pencil was used to carefully trace the edges of the seed. The projected area and the diameters of various circles inscribing and circumscribing the projected area were measured. Sphericity = di/dc …………………………….. (1) CORE Metadata, citation and similar papers at core.ac.uk Provided by International Institute for Science, Technology and Education (IISTE): E-Journals