This study investigated the effect of pretreatments on the quality characteristics of cold-pressed conophor nut (Tetracarpidium conophorum) oil with the view to promote its usage in food formulation and chemical industries. Mature conophor nuts were washed, sorted, cooked, decorticated, dried and divided into three different particle sizes (fine, coarse and whole particles). The three lots were further preconditioned to three different moisture content levels (10, 12 and 14%, wb). The preconditioned conophor nuts were cold pressed for oil extraction using a documented procedure. The physico-chemical properties of cold-pressed oil at different moisture levels (10, 12 and 14%, wb) were also investigated using standard procedures. The results obtained were analyzed using Design Expert Software Package. The results showed that both particle size and moisture content influenced oil yields. The physico-chemical property values namely iodine number, saponification value, peroxide value, acid value, refractive index at 25 °C and colour were 14.47-14.53 g I2/100 g, 395.50-396.1 mg KOH/g, 4.00 to 4.28 meq O2/g, 2.41-2.53 mg NaOH/g, 1.47-1.53 and deep yellow, respectively. The fatty acid compositions of the oil showed that saturated and unsaturated components ranged from 6.58-7.01% and 83.1-93.13%, respectively. Some of the saturated components of conophor nut oil include palmitic, cerotic, melissic, valeric and tridecyclic while its unsaturated components are oleic, isooleic, petroselinic, linolenic, alpha-linolenic and eicosatrienoic. In conclusion, the results showed that different particle sizes and moisture contents influenced oil yields. The results further showed that pretreatment affected the physico-chemical properties of the oil investigated with the exception of colour. Therefore, the properties investigated showed that the oil can find its usage in food formulation and chemical industries.
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