Enzyme‐assisted extraction of shea fat: Evidence from light microscopy on the degradative effects of enzyme treatment on cells of shea kernel meal

Abstract

AbstractA light‐microscopic study on enzyme‐treated sliced shea kernels was done to investigate the principles involved in enzyme‐assisted shea fat extraction. The raw, ellipsoidally shaped kernels, measuring 1.3 to 2.0 cm, were crosssectioned into slices of about 2‐mm thickness, which were then dissected into four or six pieces. These samples were treated with or without enzymes for predetermined periods, fixed and processed for paraffin sections (5 μm). Sections were stained with periodic acid‐Schiff base (PAS) or Coomassie blue (CB) to localize the complex polysaccharides and proteins, respectively. The cells of the enzyme‐treated samples showed distinct degradation and a high loss of cellular integrity. PAS reaction and CB staining of these cells confirmed high loss of cellular materials compared to control samples. This was also reflected in the increases of the soluble protein and free sugar contents of the effluent water collected from samples after treatment. The oilseed materials during preextraction. They thus support the principle of using enzyme treatments to improve fat yield in solvent extraction systems, as has been reported by various investigators.