22 research outputs found

    Aroma characterization of ripe date fruits (Phoemix dactylifera L.) from Algeria

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    The headspace of eight Algerian date varieties with low market value were analyzed for their aroma compounds using solid phase micro extraction and gas chromatography combined with mass spectrometry. In this study, 61 identified compounds were categorized in various chemical classes on the basis of their functional groups, alcohols, esters, aldehydes, terpenoids, ketones, hydrocarbons, and ethers. Twenty specific volatiles were found to be representative of a single variety and four shared molecules were exclusively observed in all the studied dates. Some dates such as Bent Qbala, Litima, and Timjouhart were statistically different from the other varieties which presented on the contrary a significant similarity between them. In the present study, forty eight new volatile compounds were identified which could be useful for the characterization of the Algerian date

    Evaluation of Physicochemical Properties and Sensory Qualities of Pasta Enriched with Freeze-Dried Sweet Whey

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    For food industry, the production of functional pasta from non-conventional raw materials represents a challenge. This study aims to evaluate the potential of animal proteins of freeze-dried whey as a component for pasta production and its effect on the pasta qualities and consumer acceptance. Sweet whey was freeze-dried, then directly incorporated to pasta at a 20% level. Two pasta types (pasta non-enriched vs. enriched with whey powder) were manufactured following a small-scale pilot procedure, and then evaluated for their physicochemical and sensory qualities. Results of all analyses (whey, semolina and pasta) met the standards according to international legislation; however, the characteristics of enriched pasta differed. Whey addition significantly increased ash, proteins content, optimal cooking time and water uptake (P < 0.05); it significantly decreased moisture levels, colour parameters (CIE system: a* redness, b* yellowness) and the swelling index (P < 0.05). Sensory analysis revealed that overall sensory and product quality of enriched pasta was not affected by whey fortification and it was found acceptable by panelists. This study points out that whey powder could be used for the functional pasta production to increase proteins levels

    Experimental and DFT Atomistic Insights into the Mechanism of Corrosion Protection of Low-Carbon Steel in an Acidic Medium by Polymethoxyflavones from Citrus Peel Waste

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    Developing green anticorrosive films is gaining great attention in science and engineering. Citrus fruit peels are mainly discarded as waste, although they can be an excellent repository of phytochemicals, that can be exploited as mitigating agents for corrosion. Herein, we report the high anticorrosion activity of a citrus extract for low-carbon steel in 1 M HCl solution at different temperatures. The main extract constituents were identified by MS and NMR. Two polymethoxyflavones (PMFs), namely nobiletin and heptamethoxyflavone, were identified as major constituents of the extract and the crude PMFs-based extract was investigated for corrosion protection. Using potentiodynamic polarization, weight loss and electrochemical impedance spectroscopy (EIS) methods, this extract revealed improved inhibition efficiency of 94%. The inhibition mechanism was elucidated by considering electrochemical kinetics and adsorption thermodynamics. SEM and UV–vis supported the electrochemical results. PMFs-based extract acted as a mixed-type inhibitor with a Langmuir model of adsorption. Importantly, DFT simulations provided atomic-level insights into the inhibition mechanism and unraveled donor-acceptor interactions between the methoxy groups of PMFs and iron atoms, facilitating the formation of a stable inhibition adsorption layer, and thus supporting the experimental findings. In addition to the physical barrier effect of PMF inhibitor, π -back bonding effect between PMF and steel was suggested

    Experimental and Theoretical Tests on the Corrosion Protection of Mild Steel in Hydrochloric Acid Environment by the Use of Pyrazole Derivative

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    In this study, 1,5-diallyl-1H-pyrazolo [3,4-d] pyrimidin-4 (5H)-one (PPD) was evaluated as an anticorrosion agent for mild steel (MS) in 1 M HCl. The analysis was performed by weight loss (WL), potentiodynamic polarization measurement, and electrochemical impedance spectroscopy (EIS). The Tafel polarization showed that PPD is a mixed-type inhibitor and reaches 94% of the protective efficiency at 10−3 M. EIS results indicated that the resistance to charge transfer increases with increasing inhibitor concentration and the corrosion of MS is controlled by a charge transfer process. The inhibitor adsorption on the MS surface obeyed the Langmuir’s adsorption isotherm. Thermodynamic parameters were calculated to elaborate the corrosion inhibition mechanism. The micrographic analysis revealed the existence of a barrier layer on the electrode surface with the presence of PPD. Theoretical examinations performed by electronic/atomic computer simulations confirmed that the obtained results were found to be consistent with experimental findings

    Experimental and computational aspects of green corrosion inhibition for low carbon steel in HCl environment using extract of Chamaerops humilis fruit waste

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    [EN] The inhibition effect of a methanolic extract of Chamaerops humilis (CHFE) on the corrosion of low-carbon steel in 1 M HCl solution was evaluated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy. The extract was obtained from the fruit seeds by the Soxhlet extraction method. The CHFE demonstrated promising anticorrosive performance, and the inhibition efficiency increased with increasing the concentration of the extract, peaking at 93% at only 500 ppm. Importantly, the inhibitor exhibited a remarkable stability after 48 h of immersion, reaching an efficiency of 94%. The extract revealed a mixed-type inhibitive behavior. In addition, elevating the solution temperature showed a negative influence on the inhibition efficacy. Thermodynamic parameters suggested that the steel dissolution is an endothermic, spontaneous process. In addition, the experimental findings match well with the Langmuir adsorption isotherm and physisorption of the extract prevails. Furthermore, SEM/EDX and UV-Vis analyses demonstrated that the steel surface is protected by the extract molecules, confirming the electrochemical results. Density functional theory (DFT), Fukui function and molecular dynamics (MD) calculations unraveled the nature of inhibitor-metal surface interactions and provided insights into the most favorable electrophilic and nucleophilic active sites of oleic acid, a major constituent of the extract, helping to elucidate the mechanism of corrosion inhibition at the molecular level.M. Boudalia acknowledges the support from Mohammed V University and H.M.A. Amin acknowledges the support from Cairo University.Eddahhaoui, F.; Najem, A.; Elhawary, M.; Boudalia, M.; Campos, OS.; Tabyaoui, M.; Garcia-Anton, J.... (2024). Experimental and computational aspects of green corrosion inhibition for low carbon steel in HCl environment using extract of Chamaerops humilis fruit waste. Journal of Alloys and Compounds. 977. https://doi.org/10.1016/j.jallcom.2023.17330797
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