ABSTRACT Different xanthan gum concentrations (0–0.8 %) were tested, and the rheological properti... more ABSTRACT Different xanthan gum concentrations (0–0.8 %) were tested, and the rheological properties of ice cream mixes were characterized as linear viscoelastic solids. Ostwald de Waele was successfully used to fit the steady shear data of ice cream mixes exhibiting a pseudoplastic flow (R 2 > 0.982). The samples with xanthan gum were characterized as strong gel-like macromolecular dispersions with G′ much greater than G″ but without a cross-point in the whole range of frequency applied. Cox–Merz rule was not applicable to the ice cream mixes. Steady and dynamic rheology of the ice cream mixes changed with increasing xanthan gum concentration. Besides, the four-component Burger model consisted of the association in series of the Maxwell model and the Kelvin–Voigt model was used to characterize the viscoelasticity. It was also found that the final percentage recovery parameters; J SM, J ∞, J KV, and %R (compliance of Maxwell spring and dashpot, Kelvin–Voigt element and R, respectively) of the ice cream mixes were dramatically changed by the xanthan gum concentration, increasing the internal structure parameters G 0, G 1, η 0, and η 1 (elastic moduli of Maxwell and Kelvin–Voigt springs and corresponding dashpot viscosities, respectively).
Journal of Liquid Chromatography Related Technologies, Apr 1, 2014
ABSTRACT In this study, preparative medium pressure liquid chromatography (MPLC) was used for the... more ABSTRACT In this study, preparative medium pressure liquid chromatography (MPLC) was used for the purification of some phenolic compounds including hydroxytyrosol, chlorogenic acid, and punicalagin from olive mill waste water (OMWW), European cranberrybush (Viburnum opulus L.) juice, and pomegranate peel, respectively. While the polyphenols of OMWW and European cranberrybush juice were extracted with ethyl acetate (EtOAc), methanol was used for pomegranate peel extraction. At the end of the extraction process, the solvents were removed by rotary evaporator and the residue passed into the water phase. After the centrifugation and microfiltration procedure, the injection of samples was carried out by MPLC. The outflow of the colon was collected at specific periods and the predetermined polyphenols for purification were identified with High-Pressure Liquid Chromatography with UV Detector (HPLC-UV). After the collection of defined fractions, chlorogenic acid, and punicalagin were concentrated with a rotary evaporator and transformed into particle form by freeze drying. Hydroxytyrosol was produced as concentrated liquid by using a rotary evaporator. The purities of the obtained compounds were determined as 90.2%for hydroxytyrosol, 92.5%for chlorogenic acid, and 97.1%for punicalagin. Moreover, the inhibition percentages of these compounds on 2,2-diphenyl-1-picrylhydrazyl (DPPH) were established, respectively, as 76.01, 84.90, and 94.64.
... By Mahmut Dogan*a and Attila Akgulb ... This production is mostly from seedling trees, but cu... more ... By Mahmut Dogan*a and Attila Akgulb ... This production is mostly from seedling trees, but cultivation of new walnut cultivars from selective breeding programmes in Turkey leads to a standard walnut production (Koyuncu et al., 2004; Seyhan et al., 2002). ...
ABSTRACT Different xanthan gum concentrations (0–0.8 %) were tested, and the rheological properti... more ABSTRACT Different xanthan gum concentrations (0–0.8 %) were tested, and the rheological properties of ice cream mixes were characterized as linear viscoelastic solids. Ostwald de Waele was successfully used to fit the steady shear data of ice cream mixes exhibiting a pseudoplastic flow (R 2 > 0.982). The samples with xanthan gum were characterized as strong gel-like macromolecular dispersions with G′ much greater than G″ but without a cross-point in the whole range of frequency applied. Cox–Merz rule was not applicable to the ice cream mixes. Steady and dynamic rheology of the ice cream mixes changed with increasing xanthan gum concentration. Besides, the four-component Burger model consisted of the association in series of the Maxwell model and the Kelvin–Voigt model was used to characterize the viscoelasticity. It was also found that the final percentage recovery parameters; J SM, J ∞, J KV, and %R (compliance of Maxwell spring and dashpot, Kelvin–Voigt element and R, respectively) of the ice cream mixes were dramatically changed by the xanthan gum concentration, increasing the internal structure parameters G 0, G 1, η 0, and η 1 (elastic moduli of Maxwell and Kelvin–Voigt springs and corresponding dashpot viscosities, respectively).
Journal of Liquid Chromatography Related Technologies, Apr 1, 2014
ABSTRACT In this study, preparative medium pressure liquid chromatography (MPLC) was used for the... more ABSTRACT In this study, preparative medium pressure liquid chromatography (MPLC) was used for the purification of some phenolic compounds including hydroxytyrosol, chlorogenic acid, and punicalagin from olive mill waste water (OMWW), European cranberrybush (Viburnum opulus L.) juice, and pomegranate peel, respectively. While the polyphenols of OMWW and European cranberrybush juice were extracted with ethyl acetate (EtOAc), methanol was used for pomegranate peel extraction. At the end of the extraction process, the solvents were removed by rotary evaporator and the residue passed into the water phase. After the centrifugation and microfiltration procedure, the injection of samples was carried out by MPLC. The outflow of the colon was collected at specific periods and the predetermined polyphenols for purification were identified with High-Pressure Liquid Chromatography with UV Detector (HPLC-UV). After the collection of defined fractions, chlorogenic acid, and punicalagin were concentrated with a rotary evaporator and transformed into particle form by freeze drying. Hydroxytyrosol was produced as concentrated liquid by using a rotary evaporator. The purities of the obtained compounds were determined as 90.2%for hydroxytyrosol, 92.5%for chlorogenic acid, and 97.1%for punicalagin. Moreover, the inhibition percentages of these compounds on 2,2-diphenyl-1-picrylhydrazyl (DPPH) were established, respectively, as 76.01, 84.90, and 94.64.
... By Mahmut Dogan*a and Attila Akgulb ... This production is mostly from seedling trees, but cu... more ... By Mahmut Dogan*a and Attila Akgulb ... This production is mostly from seedling trees, but cultivation of new walnut cultivars from selective breeding programmes in Turkey leads to a standard walnut production (Koyuncu et al., 2004; Seyhan et al., 2002). ...
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