Optimization of Enzyme-Assisted Hydrothermal Extraction of Shea Butter from Traditionally Pre-Treated Shea Kernels
Date
MAY, 2017
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Abstract
Enzymes can be simultaneously used to selectively release targeted fats from pretreated
Shea nut kernels and improve extraction efficiency at optimized conditions.
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: lipases, pectinases and cellulases, separately and in combination,
for Shea butter extraction. The process for enzyme mixtures was optimized at pH of
6, 3 % Enzyme-Substrate concentration, 2 hour hydrolysis time at a temperature of
60 ºC. The results showed that Shea nut paste yielding 48 % fat with pectinases (P),
52% with lipases (L) and 46% with cellulases (C). The amount of percentage fat
increased to 52, 54 and 56 at 1:1 P+C, L+C and P+L enzyme combinations
respectively. The highest extraction efficiency of 69.96% was recovered from 1:1:1
combination of all three industrial enzymes. The free fatty acids and the peroxide
value of the Shea butter recovered ranged from 1.6 ± 0.5 – 2.7 ± 0.1 mgKOH/kg and
3.6 ± 0.6 – 5.4 ± 0.2 mEq/kg respectively. Thus enzyme assisted aqueous hydrolysis
of Shea nut biomass for Shea butter production is a promising technology capable of
eliminating the drudgery with the mechanical extraction, the safety concerns with the
chemical methods and the arduous and cumbersome nature of the traditional village
extraction methods. To make this process financially practical, further work is
suggested to minimize cost with applications of modified mixes of crude enzymes.
Description
A Thesis submitted to the Department of Biochemistry and Biotechnology,
Faculty of Biosciences, College of Science in partial fulfillment of the
requirements for the degree of Master of Science in Biotechnology7