29 research outputs found

    Investigation of the Hydration Behavior of Different Sugars by Time Domain-NMR

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    The hydration behavior of sugars varies from each other and examining the underlying mechanism is challenging. In this study, the hydration behavior of glucose, fructose, allulose (aka rare sugar), and sucrose have been explored using different Time Domain Nuclear Magnetic Resonance (TD-NMR) approaches (relaxation times, self-diffusion, and Magic Sandwich Echo (MSE)). For that purpose, the effects of different sugar concentrations (2.5%, 5%, 10%, 15%, 20%, 30%, and 40%) (w/v) and hydration at different times for 1 day were investigated by T2 relaxation times and self-diffusion coefficients. Crystallinity values of the solid and hydrated sugars were also determined with MSE. Change in T2 relaxation times with concentration showed that the fastest binding with water (parallel with the shortest T2 values) was observed for sucrose for all concentrations followed by glucose, fructose, and allulose. Furthermore, dependency of T2 relaxation times with hydration time showed that sucrose was the fastest in binding with water followed by glucose, fructose, and allulose. The study showed that allulose, one of the most famous rare sugars that is known to be a natural low- calorie sugar alternative, had the lowest interaction with water than the other sugars. TD-NMR was suggested as a practical, quick, and accurate technique to determine the hydration behavior of sugars

    The Effect of Hydrolysis on the Antioxidant Activity of Olive Mill Waste

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    This study presents the effect of hydrolysis on the antioxidant activity of olive mill waste. The olive pomace samples were collected at different stages of maturity and were investigated for their phenolic content and antioxidant activity. Three different extraction procedures were employed, including methanolic maceration extraction and two hydrolysed procedures using 6 M HCL for acid hydrolysis and 10 M NaOH for alkaline hydrolysis. The total phenolic, flavonoid and ortho-diphenolic content, metal ion reducing activity, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-Diphenyl-1-picrylhydrazyl Radical Scavenging, hydrogen peroxide and superoxide scavenging activity assays were determined for the different extracts. In this study, cultivar and maturation of olives was one of the factors that affected the phenolic content in the olive pomace samples. Results show that alkaline hydrolysis had the highest antioxidant activity with respect to total phenolic content, 2,2-Diphenyl-1-picrylhydrazyl scavenging activity, metal ion reducing activity and superoxide scavenging activity, whereas acid hydrolysis had the highest 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity. The correlation analysis carried out on the different phenolic classes revealed that the total phenolic, flavonoid and ortho-diphenolic content were correlated with metal ion reducing activity and Radical Scavenging activity

    The Effect of Hydrolysis on the Antioxidant Activity of Olive Mill Waste

    No full text
    This study presents the effect of hydrolysis on the antioxidant activity of olive mill waste. The olive pomace samples were collected at different stages of maturity and were investigated for their phenolic content and antioxidant activity. Three different extraction procedures were employed, including methanolic maceration extraction and two hydrolysed procedures using 6 M HCL for acid hydrolysis and 10 M NaOH for alkaline hydrolysis. The total phenolic, flavonoid and ortho-diphenolic content, metal ion reducing activity, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-Diphenyl-1-picrylhydrazyl Radical Scavenging, hydrogen peroxide and superoxide scavenging activity assays were determined for the different extracts. In this study, cultivar and maturation of olives was one of the factors that affected the phenolic content in the olive pomace samples. Results show that alkaline hydrolysis had the highest antioxidant activity with respect to total phenolic content, 2,2-Diphenyl-1-picrylhydrazyl scavenging activity, metal ion reducing activity and superoxide scavenging activity, whereas acid hydrolysis had the highest 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity. The correlation analysis carried out on the different phenolic classes revealed that the total phenolic, flavonoid and ortho-diphenolic content were correlated with metal ion reducing activity and Radical Scavenging activity

    High hydrostatic pressure assisted extraction of pectin from sugar beet pulp

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    This study aimed to investigate the effect of high hydrostatic pressure assisted extraction (HHPE) (250, 350 and 450 MPa at 40 degrees C for 5 min with/without acid addition) of pectin from sugar beet pulp and compare its properties with pectin obtained from conventional extraction (CE). Degree of esterification (DE), galacturonic acid (Gal-A) content, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) relaxometry experiments were performed on the obtained pectin powder. HHPE (12.23 +/- 0.13%) doubled extraction yield compared to CE (6.43 +/- 0.07%). Also, HHPE and acid addition were found to have a synergetic effect on the extraction. HHPE resulted in degradations in the polymer structure and reduced Gal-A content and DE. Pectin extracted with both methods was classified as low methoxyl pectin (LMP). According to the NMR Relaxometry results, HHPE decreased water holding capacity (WHC). In brief, HHP was shown to increase the pectin extraction yield and no changes in viscosity were observed at the concentrations studied (2 g/L)

    Polysaccharide blended whey protein isolate-(WPI) hydrogels: A physicochemical and controlled release study

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    WOS: 000405058800005Design and characterization of composite whey protein isolate (WPI) hydrogels are gaining interest due to their utilization as controlled delivery matrices for bioactive agents. In this study, black carrot extract (BC) loaded composite WPI hydrogels, containing xanthan (XN), pectin (PC) and gum tragacanth (GT) were prepared by conventional water bath (CV) and infrared (IR) assisted microwave heating (MW). Release and swelling experiments were conducted at pH 7.0 phosphate buffer solution for 24 h. Highest swelling ratio (SR) was observed at CV XN hydrogels and only XN hydrogels showed a distinct increase in SR (17.85%) with respect to WPI hydrogels containing no additional polymer (10.55%) (p < 0.05). CV WPI hydrogels having no added polysaccharide showed the highest release percent (77.81%). CV PC, XN and GT hydrogels with release ratios of 37.15%, 32.79% and 29.39%, respectively, were capable of retarding release with respect to sole WPI hydrogels (p < 0.05). MW increased the release rates of all polymer added hydrogels. Nuclear Magnetic Resonance (NMR) relaxometry was used to understand the polymer water interactions in the samples. Therefore, transverse relaxation times (T-2) and self-diffusion coefficients (SDC) of each hydrogel were measured. Increasing T-2 and SDC values of CV XN samples were associated with better gel characteristics. Scanning electron microscope (SEM) images revealed the microstructural differences between the heating and polymer types. Mathematical modelling of release behaviors of hydrogels was also conducted to estimate diffusion coefficients. Moreover, this study introduces the effects of MW-IR heating on the physiochemical and controlled release behavior of WPI-GT composite hydrogels for the first time. (C) 2017 Elsevier Ltd. All rights reserved

    Investigation of the Hydration Behavior of Different Sugars by Time Domain-NMR

    No full text
    The hydration behavior of sugars varies from each other and examining the underlying mechanism is challenging. In this study, the hydration behavior of glucose, fructose, allulose (aka rare sugar), and sucrose have been explored using different Time Domain Nuclear Magnetic Resonance (TD-NMR) approaches (relaxation times, self-diffusion, and Magic Sandwich Echo (MSE)). For that purpose, the effects of different sugar concentrations (2.5%, 5%, 10%, 15%, 20%, 30%, and 40%) (w/v) and hydration at different times for 1 day were investigated by T2 relaxation times and self-diffusion coefficients. Crystallinity values of the solid and hydrated sugars were also determined with MSE. Change in T2 relaxation times with concentration showed that the fastest binding with water (parallel with the shortest T2 values) was observed for sucrose for all concentrations followed by glucose, fructose, and allulose. Furthermore, dependency of T2 relaxation times with hydration time showed that sucrose was the fastest in binding with water followed by glucose, fructose, and allulose. The study showed that allulose, one of the most famous rare sugars that is known to be a natural low-calorie sugar alternative, had the lowest interaction with water than the other sugars. TD-NMR was suggested as a practical, quick, and accurate technique to determine the hydration behavior of sugars

    NMR Relaxometry and magnetic resonance imaging as tools to determine the emulsifying characteristics of quince seed powder in emulsions and hydrogels

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    Quince seed powder (QSP) is known to exhibit emulsification properties and could be used as a natural emulsifier in colloidal food systems. In this study, emulsion-based alginate hydrogels were formulated using QSP and xanthan gum (XG) as stabilizers. The objective of the study was to show the emulsifying power of QSP in emulsions and their hydrogels using Time Domain (TD) NMR Relaxometry and Magnetic Resonance Imaging (MRI). Rheology and mean particle size measurements for emulsions and scanning electron microscope (SEM) experiments for hydrogels were further conducted as complementary methods. QSP containing emulsions were found to have longer T2 relaxation times than XG samples (p < 0.05). Addition of either QSP or XG produced a more pseudoplastic flow behavior (p < 0.05) on the emulsions. Relaxation times were also obtained by MR images through T2 maps. Relaxation decay curves showed the presence of two proton compartments in hydrogels; protons associated with the polymer matrix and protons interacting with the oil phase. The contribution of the first proton pools was the largest in QSP hydrogels confirmed by the lowest standard deviation in the T2 maps. This behavior was explained by the emulsification ability of QSP. Results showed that NMR Relaxometry and MR images could be used to understand the emulsifying nature of QSP and many other hydrocolloids

    Effect of Different Syrup Types on Turkish Delights (<i>Lokum</i>): A TD-NMR Relaxometry Study

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    Turkish delights were formulated by using sucrose (control) and different types of corn syrups (having varying glucose/fructose ratios) and allulose syrup. 30% allulose syrup and 30% sucrose-containing Turkish delights were found to exhibit an amorphous structure. Time-domain NMR relaxometry experiments were also conducted on delights by measuring T2 relaxation times, and two distinct proton populations were observed in all formulations. The use of different syrup types at different substitution levels led to significant changes in the relaxation times (T2a and T2b) of the samples, indicating that the relaxation spectrum might be used as a fingerprint for Turkish delights containing different types and amounts of syrup types. Second moment (M2) values which were measured from the signal acquired using a magic sandwich echo pulse sequence were also found to be an effective and promising indicator to detect the crystallinity of Turkish delights
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