Physico-chemical characterization of shea butter from Kaima, Western Nigeria

Abstract

The characterization of Shea butter is important to enable it meet the standard required for certification. This study aimed at evaluating the quality and physico-chemical characteristics of extracted Shea oil obtained from different types of shea kernels harvested in Kaima local government area of Kwara state with the view to assist local and international producers on the ideal shea kernel for production. The Shea kernels obtained were classified into three; intact and whole (Shea kernel in good condition, microbial and pest-infested Shea kernels and wounded Shea kernels). Moisture content, color, specific gravity (density), acid value, peroxide value, Saponification value, unsaponifiable matter, Anisidine value, iodine value, total lipid content (oil content), free fatty acids profile (using the PORIM test method 2004) were carried out on each sample.Our results showed significant differences (p< 0.0001) between the various Shea butters with the microbial and pest-infested Shea butter having the highest contribution in lowering the quality of the Shea butter. Study revealed that intact and whole Shea kernel butter had good physico-chemical characteristics when compared to the wounded and microbial and pest-infested Shea kernel butter. Free fatty acid (7.13±0.00 %, 10.66±0.03 %, 13.51±0.20 %), Acid value (14.25±0.00 mg/g ,21.32±0.07 mg/g27.01±0.40 mg/g), Peroxide value (6.06±00meq/kg, 15.19±0.03meq/kg, 31.47±0.17meq/kg), PAnisidine value( 18.37±0.07, 15.50±0.00, 13.47±0.17), Total oxidation value (24.26±0.00, 30.24±0.10, 44.08±0.17), Saponification value (227.49±4.46 mg, 164.99±0.00 mg, 181.99±5.00 mg), Unsaponifiable matter (4.51±0.00%, 4.67±0.02 %, 3.06±0.00 %), Iodine value (9.04±0.05 g, 8.74±0.02 g, 8.42±0.01 g), Moisture content (1.00±0.44 %, 0.50±0.29%, 1.00±0.29 %) respectively. This study recommends that Shea butter processors should sort the kernels into categories and process them accordingly to yield different grades for local and international market