In vitro determination of the sun protection factor of crude shea butter obtained by different processes in Burkina Faso

Shea butter is of great interest in food, cosmetic, and pharmaceutical industries. It shows antioxidant, anti-inflammatory, anti-tumor, and protease-inhibition properties. The great interest in the cosmetic sector is due to its particular unsaponifiable content (5 –7 %), and for its probable skin protection properties against UV-A and UV-B radiation. The aim of this study was to establish a relationship between sun protection factor and crude shea butter.
Thirty-seven samples obtained by 32 extraction processes were collected from 11 regions of Burkina Faso. The sun protection factor was evaluated in vitro by UV-Vis spectrophotometry, according to the method of Mansur using the relationship between erythemogenic effect and radiation intensity at each wavelength. Sample kariten free was used to establish kariten ability in sun protection factor.
Six major steps were identified as having an impact on the finished product quality. The churning process was the most important one. A relationship between the sample origin and the type of extraction process used could not be established. According to experimental conditions, sun protection factor average values were not statistically significant, with p-value = 0.228. The average value of sun protection factor of all individuals (20.49) was not significantly different to value for sample kariten free (20.88), at P ≤ 0.05.
Butter had mainly a moderate sun protection factor. Alternative methods should be explored to investigate the relationship between SPF and kariten in order to ensure the results obtained.