Preliminary TLC Analysis of Fructooligosaccharides as Feed Additives

A rapid, simple qualitative thin-layer chromatographic method has been developed for separation of mono- and fructooligosaccharides from feed additives with the aim of analyzing them in biological materials. The fructooligosaccharides were analyzed in the commercially available dietetic feeding products Raftifeed and Raftilose (Orafti, Tienen, Belgium) and in the polysaccharide maltodextrin. Silica gel layers were pretreated either with sodium acetate or with a mixture of chloroform and methanol, and three different mobile phases were used. High-performance amino-bonded layers were developed with acetonitrile—water—phosphate buffer without previous pretreatment of the layers. Post-chromatographic derivatization of chromatograms was accomplished with diphenylamine—aniline—phosphoric acid reagent. Densitometric evaluation of chromatograms was performed at λ = 370 nm.