The kernel is the oil-bearing material that can be obtained by processing the shea nut fruit. The fruit primarily undergoes several processes – de-pulping, boiling, drying, deshelling, winnowing and sorting – to obtain the kernel from which the shea butter is extracted. Mechanical processing technology
How is shea butter extracted?
Extraction of shea butter from shea kernels can be done via either water extraction i.e. boiling with water, mechanical extraction, solvent extraction, or a combination of these processes. The traditional method of how shea butter is made involves water extraction – boiling the shea kernels with water and skimming off the released oils.
How are shea nuts processed?
Subsequently, the nuts are processed by boiling, roasting, or sun-drying. Boiling in water prevents the shea seeds from germinating and prevents hydrolytic degradation of the extracted shea butter. The boiled shea nuts are sun-dried, and then the dried shea nuts are cracked to obtain the kernels.
Does shea butter need solvent extraction?
For these reasons, solvent extraction is generally not preferred for shea butter extraction—especially in food and cosmetic markets where consumers seek natural, organic ingredients. What is shea oil? Traditional water extraction, mechanical expeller pressing, and solvent extraction yield shea butter.
How is shea oil extracted?
As a result, many shea producers are adopting more mechanized solutions to improve quality and yield. Larger processors use mechanical extraction equipment to recover more oil efficiently. Screw press expellers physically crush the shea kernels to squeeze out shea oil from the solid meal, which exits the expeller as a cake.
What is the mechanical press method of shea butter extraction?
The mechanical press method of shea butter extraction has been reported by FAO and CFC (2002) but one of the earliest research on the use of the mechanical press was by Marchand (1988). His research revealed that equipped with a jack that exerts 30 tonnes of force, a shea butter press could crush more than 3 kg of shea kernels within 20 minutes.