Carob (Ceratonia siliqua L) Seed Tegument Separation and Analysis: Comparison with Locust Bean Gum Hot-Water-Insoluble Residue Monosaccharide's Composition

Patrick Aubin DAKIA, Marie Michele Agnan COMBO, Beda Marcel YAPO, David Kouakou BROU , Michel PAQUOT

The proximate composition of the carob seed hull were analyzed in order to evaluate the effect of carob seed tegument fragments (as contaminants) on locust bean gum (LBG, a galactomannan usually used as food additive) composition. It has been observed that the hot-water-insoluble residue, recovered after LBG flour dissolution and centrifugation, contains about 71-100% of total arabinose, xylose and rhamnose present in LBG crude flour. These results suggest the presence of non-galactomannan polysaccharides in LBG flour. The separation of the seed components by boiling water pre-treatment furnished ~30% of brown coat. The seed coat sugar composition, determined by GC analysis after partial acid hydrolysis, shown that arabinose (~20%) and xylose (6%) are the major monosaccharides in the hull polysaccharides (theorically from hemicelluloses fraction (≥20%)).

It can suggest that the minors sugars as arabinose, xylose and rhamnose, usually determined in carob gum analysis, came from the small pieces of seed husk remaining in gum flour during its primary extraction process.