). However, a feature from the cellulose that appeared differently
is the peak at 1295 cm−1, which had a significantly higher
intensity in the bleached carrot spectrum than in the bleached BSG
spectrum. The differences in peak intensities and ratios translate
to differences in the structural properties of these materials. However,
the main difference in the spectra between the two residues
was a sharp peak with medium intensity at 860 cm−1 that can
be seen only in the carrot sample and is characteristic for pectin
(Mathlouthi and Koenig, 1986). This confirmed the presence of
pectin after the pretreatment. The spectra of the samples after
grinding were similar to those of the bleached samples, especially
in the case of carrot, where almost no changes in the spectra can
be seen. In the case of BSG, some slight alterations in the structure
of cellulose can be presumed because changes in the intensity
of the peaks associated with cellulose can be observed, especially
between1260 and1470 cm−1.Anintensitydifference was observed
around 1600 cm−1 in the bleached BSG in comparison with the
BSG nanofibers. This difference was attributed to background noise,
appearing at a high level of intensity due to the weaker cellulose
signal found in the bleached BSG compared to the BSG nanofibers.
Thus, the ratio of cellulose to noise signals is lower for the bleached
BSG in the normalized spectra.