The kernel of the fruit contains many acids. This class is represented by
оctadecanoic acid (6.02%), (9Z,12Z)-octadeca-9,12-dienoic acid (4.2%), hexadecanoic
acid (5.4%),(9Z)-octadec-9-enoic acid (6.1%), (9Z,12Z,15Z)-9,12,15-octadecatrienoic
acid (0.63%). The extract of apricot pomace contains comparatively high amount of
terpene alcohols: linalool (3.06%), α-terpineol (5.98%), nerol (3.02%), geraniol
(8.54%), isoborneol (1.03%), nerolidol (8.54%), farnesol (1.38%) and others. These
compounds represented over 18% of the total volatiles in apricot pomace.
The presence of the functional groups of the higher organic compounds in the
extract is confirmed by the analysis of the liquid phase of the extract of the apricot
grinders by IR spectroscopy. FT-IR analysis was held by Bruker Tensor 27 FTIR
spectrometer in attenuated total reflection mode (Pike Technologies, GladiATR for
FTIR with diamond crystal) and using spectral range of 4000–400 cm
−1
with resolution
of 4 cm
−1
. The IR spectrum (Figure 2) is a classical spectrum with a good resolution of
lines and an even base, which indicates the chemical stability of the sample. There are
often colloidal systems in extracts which distort the baseline.
The moisture content of the sample greatly broadens the peaks. In the spectrum,
it is possible to distinguish absorption bands in the region of 3000-2800 cm
-1
, which
probably indicates the presence of an intermolecular hydrogen bond. The presence of
aliphatic CH
3
and CH
2
groups is indicated by strong absorption in the 2930-2850 cm
-
1
region (valence vibrations of CH
3
and CH
2
groups) and in the region of 1463-1377
cm
-1
(deformation vibrations). A number of signals in the 902 cm
-1
region indicate the
vibrations of the CH bonds. There are also absorption bands in the range of 1611-1617
cm
-1
, 1505 and 3400 cm
-1
, characteristic for vibrations of aromatic structures.
Figure2. FT-IR of apricot pomace extract by 2-propanol.
It should be noted that along with aromatic compounds there are compounds
with conjugated double bonds (such as conjugated dienes), that are evidenced by the
presence of the absorption band in the spectrum at 1653 and 973 cm
-1
. The IR spectrum
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