If the analytical evaluation of the authenticity of the product
by means of infrared spectroscopy should be rapid and reliable,
the problem of scanning spectra of samples containing different
water content can rise (Kacˇura´kova´ and Mathlouthi, 1996;
Kacˇura´kova´ & Wilson, 2001). In order to see if the water
absorbed by these compounds during their storage affects the
spectra, six monosaccharides, three disaccharides, four carrageenans, four pectic polysaccharides, three galactans, two
glucans and one commercial mixture of carrageenan–pectin
submitted to a hydrated environment and in solution were
studied in the FT-IR 1200–800 cmK1 region and compared
with those from the dry samples.