Optimisation de la torrefaction des amandes de P. Butyracea pour la production du beurre
Pentadesma butyracea kernels roasting during butter production is an operation which affects the extraction yield and the quality of butter. In order to produce a good quality of P. butyracea butter and improve yield extraction, this work aims to determine the optimal roasting time and temperature. Thus, the dried P. butyracea kernels were roasted at temperature from 100 to 180°C during 15 to 45min using Response Surface Method with central composite design. In response to these different treatments, yield of cold extraction with hexane, kernels (color : lightness (L*), redness (a *) and yellowness (b*)) and butter quality (color : lightness (L*) and yellowess (b*) ; acidity ; peroxide index) were assessed. The linear and/or quadratic effect of the duration and the temperature of roasting as well as the interaction between these two factors strongly influenced extraction yield, physical characteristics of the kernels and physicochemical characteristics of the butter. At 135°C for 45 min it is possible to produce Pentadesma butter for cosmetic and food industries uses (acidity : 0.31 % ; peroxide index : 3.22 méq O2/Kg ; L* : 75.10 ; b* : 35.02) with an extraction yield of about 40 % (39.5 %).
Keywords: Shea butter, Chocolate industry, Cosmetics, Peroxide index, Benin