Abstract

Three different pre-treated shea nut substrates: raw kernels, roasted kernels and shea nut paste from roasted kernels were subjected to treatment with three different industrial enzymes: lipase, pectinase and cellulase, separately and in combination for shea butter extraction. Enzyme mixtures was optimized at pH of 6; 3% enzyme-substrate concentration, 2 h hydrolysis time at a temperature of 60ºC. The results showed that shea nut paste yielded 48% fat with pectinases (P), 52% with lipases (L) and 46% with cellulases (C) and this made it the best substrate for shea butter recovery. The amount of fat percentage wise with the same substrate increased to 52, 54 and 56 at 1:1 P+C, L+C and P+L enzyme combinations respectively. The highest extraction efficiency of 70% was recovered from 1:1:1 combination of all three industrial enzymes. Therefore, enzyme assisted aqueous hydrolysis of shea nut biomass for shea butter production is a promising technology with a great potential (extraction efficiency and safety) to substitute traditional extraction methods.

Key words: Shea kernels, shea butter, traditional extraction, solvent extraction, commercial enzymes.