Fig 1.
Schematic diagram of the cold press oil extraction setup.
Fig 2.
Visual display of cold pressed, chemically extracted and eight commercial canola brands purchased from local markets of Islamabad, Pakistan.
Fig 3.
Fluorescence spectra of cold pressed, chemically extracted and commercial brands of canola oil samples using excitation wavelengths in the range 280–420 nm.
Fig 4.
(a) Fluorescence spectra of non-heated and heated commercial brand-2 at different temperatures of 100, 150, 200 and 250°C and vitamin E. (b) PCA scatter plot between PC1 & PC2, which classify the non-heated and heated commercial brand-2, of whom spectra are shown in Fig 4A. PC1 explains 92% and PC2 6% variance in the data.
Fig 5.
(a) Fluorescence spectra of eight commercial brands available in local markets of Islamabad. (b) PCA scatter plot between PC1 & PC2 which classify eight commercial brands of whom emission spectra is shown in Fig 6A.
Fig 6.
(a) Fluorescence spectra of vitamin E, canola oil samples extracted by cold press, chemical method and eight commercial brands when excited at 330 nm. (b) PCA scatter plot between PC1 & PC2 shows the classification among vitamin E, cold press, chemically extracted and eight commercial brands of canola oil, whom spectra are shown in Fig 6A. (c) Fluorescence spectra of cold pressed, chemically extracted and eight commercial brands of canola oil when excited at 410 nm. (d) PCA scatter plot between PC1 & PC2 shows the classification among cold pressed, chemically extracted and eight commercial brands of canola oil, whom spectra are shown in Fig 6C.
Fig 7.
Visual display of non-heated and heated cold pressed canola oil samples at 100, 110, 120, 130, 140, 150, 160, 170, 180, 200 and 250°C.
Fig 8.
(a) Fluorescence spectra of non-heated and heated cold pressed canola oil samples at 100, 110, 120, 130, 140, 150, 160, 170, 180, 200 and 250°C when excited at wavelength of 330 nm. (b) PCA scatter plot between PC1 and PC2 which shows classification between non-heated and heated cold pressed canola oil samples, whom spectra are shown in Fig 8A. PC1 explains 87% and PC2 7% variances in the data. (c) Emission spectra of non-heated and heated cold press oil samples at 100, 110, 120, 130, 140, 150, 160, 170, 180, 200 and 250°C when excited at wavelength of 410 nm. (d) PCA scatter plot between PC1 and PC2 which shows classification among non-heated and heated cold pressed canola oil samples, whom spectra are shown in Fig 8C. PC1 explains 99% and PC2 1% variances in the data.
Fig 9.
(a) Fluorescence spectra of non-heated and heated cold pressed oil samples at 100°C when excited at 330 nm. (b) The PCA scatter plot between PC1 & PC2 which shows classification between the non-heated and heated cold pressed oil sample at 100 oC, whom spectra are shown in Fig 9A. (c) Loading vector of PC1, which are produced from florescence spectra shown in Fig 9A. (d) Loading vector of PC2, which are produced from florescence spectra shown in Fig 9A.