Mechanical properties of agricultural materials are necessary for the proper design and development of their planting, harvesting, handling and processing machineries. In this research, fracture resistance of whole gmelina seed was evaluated in terms of its rupture force, rupture energy and deformation at rupture under four moisture content levels and three loading rates. The quasi-static compressive tests were conducted at 20, 25, 30 and 35 percent moisture levels (wb); and 5, 10 and 15 mm/min loading rates. Based on the results obtained, moisture content and loading rate had significant (P ≤0.05) effect on all the three parameters investigated. The force required for initiating seed rupture decreased with increase in moisture content and loading rate. The highest rupture energy was 0.268 Nm at 35% moisture content under 5mm/min loading rate, and the lowest was 0.116 Nm at 20% moisture content under 15 mm/min loading rate. In addition, the deformation capability of the seed decreased from 1.017 mm at 35% moisture content (wb), under 5 mm/min loading rate, to 0.458 mm at 20% moisture content (wb) under 15 mm/min loading rate. The results obtained from this research would be useful in the design and development of machines used in gmelina seed processing operations.

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The compressive behaviours (compressive strength, compressive energy, Young’s modulus, failure time, and compressive strain) of epoxy composite board, reinforced with oil bean pod shell particulates (OBPS) and mahogany timber saw dust (SD) were investigated in this research. The samples were prepared with five different fillers (OBPS and SD) percentage (10, 15, 20, 25 and 30 vol.%) in the ratio of 1:1. Both filler materials where treated with 5(w/v)% Sodium hydroxide solution to enhance their mechanical properties. All the composite samples were tested according to ASTM standards, by using the Universal Testing Machine. Results obtained from the research showed that fillers loading had significant (P ≤0.05) effect on all the compressive behaviours investigated. In addition, the results showed that the fillers significantly improved all the compressive parameters. The compressive strength of the composite increased from 14.54 to 48.19 MPa, as the fillers loading increased from 10 to 30 wt.%, while the Young’s modulus increased by 49%.  The compressive energy increased from 21.4 to 146 Nm. Data gotten from this research can be useful in the production of composite boards for engineering applications.

Instrumental texture profile analysis (TPA) of Nandini cucumber fruit, was measured as a function of its parts (stalk, mid and blossom), and maturity stages. These textural parameters; hardness, springiness, adhesiveness, gumminess, stringiness, fracturability, and chewiness of the fruit were measured; over a course of four maturity stages, 6, 9, 12 and 15 Days after Peak Anthesis (DAPA). The texture profile analysis was done by using the Warner-Bratzler shear force (WBS) method, and the results showed that maturity stage and fruit part significantly (P ≤ 0.05) influenced all the textural parameters evaluated. Over the course of maturation, all the parameters investigated were found to increase. During maturation, the stalk, mid and blossom hardness increased by 25, 26 and 32% respectively; springiness increased by 6.4, 7.7 and 6.2 % in the stalk, mid and blossom; gumminess increased by 57.7, 57.4 and 42.2% in the stalk, mid and blossom; chewiness increased by 60.5, 63.1 and 47% in the stalk, mid and blossom; fracturability increased from 89.13 to 118.29, 82.76 to 110.7 and 62.28 to 90.

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