Spectroscopy and spectrometry of lipids — Part 1

Preliminary Evaluation of the Application of the Ftir Spectroscopy to Control the Geographic Origin and Quality of Virgin Olive Oils

“…The importance of IR spectroscopy in the identification of molecular structures derives from the high information content of an IR spectra and the possibility to assign specific absorption bands to functional groups. As reported by several authors (van de Voort and Sedman 2000; Dobson 2001; Vlachos et al. 2006), in oils and lipids, most of the peaks and shoulders of the spectrum are attributable to specific functional groups.…”

Preliminary Evaluation of the Application of the Ftir Spectroscopy to Control the Geographic Origin and Quality of Virgin Olive Oils

“…The importance of IR spectroscopy in the identification of molecular structures derives from the high information content of an IR spectra and the possibility to assign specific absorption bands to functional groups. As reported by several authors (van de Voort and Sedman 2000; Dobson 2001; Vlachos et al. 2006), in oils and lipids, most of the peaks and shoulders of the spectrum are attributable to specific functional groups.…”

Third-harmonic generation susceptibility spectroscopy in free fatty acids

“…2(c), we reproduce the schematic structure of a single OA (C 18 H 34 O 2 ) molecule and LA (C 18 H 34 O 2 ) molecule, respectively. According to previous studies, the appearance of the absorption peaks around 1180 to 1230 nm is quite typical in most biological oils, 22,42 which corresponds to the second overtone of C─H stretching vibration of various chemical groups (─CH2, ─CH3, ─CH═CH─). However, to our surprise, experimental results have shown that the maximum THG χ ð3Þ values of both fatty acids exist outside this expected absorption wavelength range (1180 to 1210 nm), which was claimed in previously published data on a mixed oil.…”

“…46 Conventional IR spectroscopy plays an important role in elucidation of molecular structures based on molecule-specific absorption spectra (such as fingerprint region) in the range about 1000 to 4000 cm −1 . 22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples.…”

“…22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples. NIR spectroscopy has now been applied to the prediction of the composition of edible lipids 47 as well as to the determination of the trans lipid content iodine value and the saponification number of edible lipids.…”

High-Quality Fuel from the Upgrading of Heavy Bio-oil by the Combination of Ultrasonic Treatment and Mutual Solvent

“…The functional groups in the blend of mutual solvent and heavy bio-oil can be figured out from FT-IR analysis. The tensile vibration between 3100 and 3700 cm –1 was observed by FT-IR measurement due to the accumulation of −OH from water, hydroperoxide (ROOH), and their decomposition products (ROH) . The characteristic peak appearing at 2926 cm –1 belongs to the aliphatic C-stretching vibration, and the characteristic peak observed at 2854 cm –1 is due to the aliphatic C–H stretching vibration in the blend. , The peak at 1617 cm –1 is in the 1650–1550 cm –1 spectral range, which corresponds to the CC stretching of the fatty acid unsaturation; the peak at 1457 cm –1 is attributed to C–H bending symmetry, symmetry, or shear vibration .…”

Preliminary Evaluation of the Application of the Ftir Spectroscopy to Control the Geographic Origin and Quality of Virgin Olive Oils

“…The importance of IR spectroscopy in the identification of molecular structures derives from the high information content of an IR spectra and the possibility to assign specific absorption bands to functional groups. As reported by several authors (van de Voort and Sedman 2000; Dobson 2001; Vlachos et al. 2006), in oils and lipids, most of the peaks and shoulders of the spectrum are attributable to specific functional groups.…”

Third-harmonic generation susceptibility spectroscopy in free fatty acids

“…2(c), we reproduce the schematic structure of a single OA (C 18 H 34 O 2 ) molecule and LA (C 18 H 34 O 2 ) molecule, respectively. According to previous studies, the appearance of the absorption peaks around 1180 to 1230 nm is quite typical in most biological oils, 22,42 which corresponds to the second overtone of C─H stretching vibration of various chemical groups (─CH2, ─CH3, ─CH═CH─). However, to our surprise, experimental results have shown that the maximum THG χ ð3Þ values of both fatty acids exist outside this expected absorption wavelength range (1180 to 1210 nm), which was claimed in previously published data on a mixed oil.…”

“…46 Conventional IR spectroscopy plays an important role in elucidation of molecular structures based on molecule-specific absorption spectra (such as fingerprint region) in the range about 1000 to 4000 cm −1 . 22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples.…”

“…22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples. NIR spectroscopy has now been applied to the prediction of the composition of edible lipids 47 as well as to the determination of the trans lipid content iodine value and the saponification number of edible lipids.…”

High-Quality Fuel from the Upgrading of Heavy Bio-oil by the Combination of Ultrasonic Treatment and Mutual Solvent

“…The functional groups in the blend of mutual solvent and heavy bio-oil can be figured out from FT-IR analysis. The tensile vibration between 3100 and 3700 cm –1 was observed by FT-IR measurement due to the accumulation of −OH from water, hydroperoxide (ROOH), and their decomposition products (ROH) . The characteristic peak appearing at 2926 cm –1 belongs to the aliphatic C-stretching vibration, and the characteristic peak observed at 2854 cm –1 is due to the aliphatic C–H stretching vibration in the blend. , The peak at 1617 cm –1 is in the 1650–1550 cm –1 spectral range, which corresponds to the CC stretching of the fatty acid unsaturation; the peak at 1457 cm –1 is attributed to C–H bending symmetry, symmetry, or shear vibration .…”

Preliminary Evaluation of the Application of the Ftir Spectroscopy to Control the Geographic Origin and Quality of Virgin Olive Oils

“…The importance of IR spectroscopy in the identification of molecular structures derives from the high information content of an IR spectra and the possibility to assign specific absorption bands to functional groups. As reported by several authors (van de Voort and Sedman 2000; Dobson 2001; Vlachos et al. 2006), in oils and lipids, most of the peaks and shoulders of the spectrum are attributable to specific functional groups.…”

Third-harmonic generation susceptibility spectroscopy in free fatty acids

“…2(c), we reproduce the schematic structure of a single OA (C 18 H 34 O 2 ) molecule and LA (C 18 H 34 O 2 ) molecule, respectively. According to previous studies, the appearance of the absorption peaks around 1180 to 1230 nm is quite typical in most biological oils, 22,42 which corresponds to the second overtone of C─H stretching vibration of various chemical groups (─CH2, ─CH3, ─CH═CH─). However, to our surprise, experimental results have shown that the maximum THG χ ð3Þ values of both fatty acids exist outside this expected absorption wavelength range (1180 to 1210 nm), which was claimed in previously published data on a mixed oil.…”

“…46 Conventional IR spectroscopy plays an important role in elucidation of molecular structures based on molecule-specific absorption spectra (such as fingerprint region) in the range about 1000 to 4000 cm −1 . 22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples.…”

“…22 As for the NIR spectral range between 5000 to 10;000 cm −1 (1000 to 2000 nm wavelength), the absorption spectra of oils are composed of wide overlapping overtones and combinational bands. 22,40 With the benefit of computer and algorithm, chemometric methods such as principal component analysis and partial least square regression have shown success in quantitative composition analysis of mixed samples. NIR spectroscopy has now been applied to the prediction of the composition of edible lipids 47 as well as to the determination of the trans lipid content iodine value and the saponification number of edible lipids.…”

High-Quality Fuel from the Upgrading of Heavy Bio-oil by the Combination of Ultrasonic Treatment and Mutual Solvent

“…The functional groups in the blend of mutual solvent and heavy bio-oil can be figured out from FT-IR analysis. The tensile vibration between 3100 and 3700 cm –1 was observed by FT-IR measurement due to the accumulation of −OH from water, hydroperoxide (ROOH), and their decomposition products (ROH) . The characteristic peak appearing at 2926 cm –1 belongs to the aliphatic C-stretching vibration, and the characteristic peak observed at 2854 cm –1 is due to the aliphatic C–H stretching vibration in the blend. , The peak at 1617 cm –1 is in the 1650–1550 cm –1 spectral range, which corresponds to the CC stretching of the fatty acid unsaturation; the peak at 1457 cm –1 is attributed to C–H bending symmetry, symmetry, or shear vibration .…”