Analysis of sugar mixtures by modern liquid chromatographic techniques, bot
h column and planar, has gained in prominence. As far as planar chromatogra
phy is concerned, the introduction of high performance bonded-phase layers
and instrumental development techniques has opened up new avenues in the TL
C analysis of sugars, especially for samples that normally require cumberso
me clean-up processes. In chromatography, gradient elution is the technique
of choice when the mixture components span a wide range of polarities (or
molecular structure). Planar chromatography gradient development is also po
ssible using an automated technique (AMD), which has been recently introduc
ed. This technique makes large spot capacities possible because of the reco
ncentration effect caused by the multiple development as well as the accomm
odation of many spots on the same chromatographic plate, because of the gra
dient development. Thus, complex samples, such as beet or cane molasses, ca
n be analyzed (or at least screened) on high-performance thin layers using
modern scanners which allow a great deal of information to be obtained. In
the analysis of molasses, over pressure liquid chromatography (OPLC) is als
o interesting. This is a forced flow technique which makes both large spot
capacities and short development times possible, and can be utilized for gr
adient elutions as well. Details of the analysis of both beet and cane mola
sses are reported, and a comparison between the two techniques mentioned pr
eviously is discussed. (C) 1998 Elsevier Science Ltd. All rights reserved.