Greyt et al. [69] revealed that a reduction in the amount of husks could improve the oil yield, increase the protein content and reduce the fibre content as illustrated in Fig. 9. The reported oil yield could be improved by around 20% by reducing the husk content to 5%. However, Greyt et al. [69] commented that a zero level of husk is not encouraged since the consequent press on the soft kernels is difficult. This might be due to slip and the pressed kernels may turn into a paste inside the press tool. With regard to this issue, Beerens [59] reported that a reduction of the husk content to 66% could reduce the oil recovery of BT50 press due to the slip of solid–oil mixture. A modification of the press tool to process seeds with low husk content is necessary. Further, the higher fibre content of the undehulled seeds can increase the wear of the press. Table 4 shows the effect of husk content on the level of oil recovery based on previous research. A zero husk content could improve the oil yield by 26.8%. A high quality crude oil should be free of impurities or sediment such as husk particles. Therefore, one of the direct ways to improve oil quality is to reduce the husk content. A seed cleaning process has been proposed to remove the husks from the whole seeds in order to produce kernels with purity as high as possible prior to the oil extraction process for better oil quality. In addition, the presence of husk content leads to more solvent required during solvent extraction process and thus the husk content should be reduced in order to save the solvent extraction cost.