16 research outputs found

    Application of Differential Pulse Voltammetry to Determine the Efficiency of Stripping Tocopherols from Commercial Fish Oil

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    There has been an increase in the use of electrochemical methods for monitoring antioxidant levels in a variety of disciplines due to the sensitivity, low detection limits, ease of use, low cost and rapid analysis time offered by these techniques. One technique that has received specific attention is differential pulse voltammetry. We describe a novel application of differential pulse voltammetry to quantitatively and qualitatively determine the efficiency of removing tocopherols from commercial fish oil via column chromatographic separation. The relative limits of detection and quantitation of differential pulse voltammetry are compared to HPLC for determining the removal of tocopherols from commercial fish oil. It was determined that differential pulse voltammetry can monitor the separation of commercially added antioxidants from the bulk sample via a decrease in antioxidant oxidation currents. Furthermore, the limits of detection and quantitation were found to be comparable with values obtained using HPLC for tocopherol identification and quantitation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141339/1/aocs0527.pd

    Oxidation of Fish Oil Oleogels Formed by Natural Waxes in Comparison With Bulk Oil

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143663/1/ejlt201700378.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143663/2/ejlt201700378_am.pd

    Detection of corn adulteration in Brazilian coffee (Coffea arabica) by tocopherol profiling and Near-Infrared (NIR) spectroscopy

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    Coffee is a high-value commodity that is a target for adulteration, leading to loss of quality and causing significant loss to consumers. Therefore, there is significant interest in developing methods for detecting coffee adulteration and improving the sensitivity and accuracy of these methods. Corn and other lower value crops are potential adulterants, along with sticks and coffee husks. Fourteen pure Brazilian roasted, ground coffee bean samples were adulterated with 1–20% of roasted, ground corn and were analyzed for their tocopherol content and profile by HPLC. They were also analyzed by near-infrared (NIR) spectroscopy. Both proposed methods of detection of corn adulteration displayed a sensitivity of around 5%, thus representing simple and fast analytical methods for detecting adulteration at likely levels of contamination. Further studies should be conducted to verify the results with a much larger sample size and additional types of adulterants

    Seasonal variation, fractional isolation and nanoencapsulation of antioxidant compounds of Indian blackberry (Syzygium cumini)

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    Indian blackberry (Syzygium cumini L.) is an evergreen tree in the Myrtaceae family. It is used in traditional medicine due to its significant bioactivities and presence of polyphenols with antioxidant activities. The present study describes the effect of seasonal variations on Indian blackberry leaf essential oil yield and chemical composition, production of fractions from essential oil using high vacuum fractional distillation and slow cooling to low temperature (−50 °C) under vacuum, and bioactivities of the essential oil, fractions, and nanoparticles. The results show that Indian blackberry essential oil yield was higher in spring season as compared to winter season. Indian blackberry essential oil fractionation processes were effective in separating and concentrating compounds with desired bioactivities. The bioactivities shown by magnesium nanoparticles were comparatively higher than barium nanoparticles

    Detection of Corn Adulteration in Brazilian Coffee (Coffea arabica) by Tocopherol Profiling and Near-Infrared (NIR) Spectroscopy

    No full text
    Coffee is a high-value commodity that is a target for adulteration, leading to loss of quality and causing significant loss to consumers. Therefore, there is significant interest in developing methods for detecting coffee adulteration and improving the sensitivity and accuracy of these methods. Corn and other lower value crops are potential adulterants, along with sticks and coffee husks. Fourteen pure Brazilian roasted, ground coffee bean samples were adulterated with 1–20% of roasted, ground corn and were analyzed for their tocopherol content and profile by HPLC. They were also analyzed by near-infrared (NIR) spectroscopy. Both proposed methods of detection of corn adulteration displayed a sensitivity of around 5%, thus representing simple and fast analytical methods for detecting adulteration at likely levels of contamination. Further studies should be conducted to verify the results with a much larger sample size and additional types of adulterants

    Wild brazilian mustard (Brassica juncea L.) seed oil methyl esters as biodiesel fuel

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    Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)‐docosenoic; 45.7 wt.%) acid, with linoleic (9(Z),12(Z)‐octadecadienoic; 14.2 wt.%) and linolenic (9(Z),12(Z),15(Z)‐octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm^2 s^−1 (40 °C) and 4.8 h (110 °C), respectively. The cloud, pour and cold filter plugging points were 4, −21 and −3 °C, respectively. Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity, as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751 and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production

    Wild Brazilian Mustard (Brassica juncea L.) Seed Oil Methyl Esters as Biodiesel Fuel

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    Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)‐docosenoic; 45.7 wt.%) acid, with linoleic (9(Z),12(Z)‐octadecadienoic; 14.2 wt.%) and linolenic (9(Z),12(Z),15(Z)‐octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm^2 s^−1 (40 °C) and 4.8 h (110 °C), respectively. The cloud, pour and cold filter plugging points were 4, −21 and −3 °C, respectively. Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity, as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751 and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production
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