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Effect of Drying Temperature on Physiochemical Properties of Powder from Blanched and Unblanched Lemon Peel and Sensory Quality Evaluation of the Powder Fortified Biscuits
Get PDFPreparation of biscuit incorporating lemon peel powder can be a new approach in formulating fortified fast food. This investigation was made to evaluate quality of prepared biscuits with lemon peel powder. The effect of temperature on drying time and physiochemical properties of lemon peel powder and their effects on biscuits were also examined. Two drying temperatures (650C and 750C) were employed for both blanched and unblanched lemon peel. The formulated biscuit samples incorporating 1 % lemon peel powder were compared with control biscuits which were prepared with 100% wheat flour. It took longer time (18 hr) for drying of blanched sample at 65 0C whereas shorter time (8 hr) was required for that of blanched sample at 750C. There was a significant decrease in the physiochemical properties of lemon peel powder with the increase of temperature except protein and fibre content. In addition, moisture content of the unblanched sample was found to be lower than the blanched sample at the same temperature. Significantly higher ascorbic acid was obtained by the unblanched samples. Protein and fibre content for both unblanched and blanched sample at the same temperature were found to be higher. All the samples were significantly different at 5% level of significance for overall acceptability. Biscuits prepared with unblanched dried lemon peel powder (at 650C) sample secured the highest score in case of all the sensory parameters. Therefore, quality fortified biscuit can be prepared commercially by incorporating 1 % lemon peel powder in wheat flour for the fast food consumer
Cloud Point Extraction Used for Separation and Preconcentration of Trace Elements in Food Samples: A Review of Recent Applications
Get PDFFood safety analysis involves many subfields. One of them is inorganic analysis aimed to the quantification of various trace elements. The main attention in this field is paid to toxic, potentially toxic, and essential trace elements. However in many cases, direct quantification of trace elements in a complex food matrix is almost impossible. To resolve this problem, a combination of a suitable separation procedure with a reliable quantification method is required to deliver accurate results. One of the separation techniques that is currently receiving considerable attention is cloud point extraction (CPE). The use of optimized CPE procedures with commonly available spectrometric methods (e.g., UV-Vis spectrophotometry, flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry, hydride generation atomic absorption spectrometry, cold vapor atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry) provides the powerful tool for reliable quantification of many trace elements (e.g., Al, As, Cd, Cu, Hg, Pb, Mn, Ni, Sb, Se, Sn, Zn, and many others) in various types of food matrices (e.g., fresh vegetables, ground grain samples, canned food samples, various powdered food samples, and many others), as documented by studies included in this review
Closed-Loop Drive Detection and Diagnosis of Multiple Combined Faults in Induction Motor Through Model-Based and Neuro-Fuzzy Network Techniques
Get PDFIn this paper, a fault detection and diagnosis approach adopted for an input-output feedback linearization (IOFL) control of induction motor (IM) drive is proposed. This approach has been employed to detect and identify the simple and mixed broken rotor bars and static air-gap eccentricity faults right from the start its operation by utilizing advanced techniques. Therefore, two techniques are applied: the model-based strategy, which is an online method used to generate residual stator current signal in order to indicate the presence of possible failures by means of the sliding mode observer (SMO) in the closed-loop drive. However, this strategy is not able to recognise the fault types and it can be affected by the other disturbances. Therefore, the offline method using the multi-adaptive neuro-fuzzy inference system (MANAFIS) technique is proposed to identify the faults and distinguish them. However, the MANAFIS required a relevant database to achieve satisfactory results. Hence, the stator current analysis based on the HFFT combination of the Hilbert transform (HT) and Fast Fourier transform (FFT) is applied to extract the amplitude of harmonics due to defects occur and used them as an input data set for the MANFIS under different loads and fault severities. The simulation results show the efficiency of the proposed techniques and its ability to detect and diagnose any minor faults in a closed-loop drive of IM
Control of Electrodialysis Desalination Systems as Smart Loads in Microgrids with High Penetration of Renewable Generation
Get PDFWater desalination systems connected to microgrids with high penetration of renewable energy generation are frequently used to promote the development of remote areas. These microgrids often have power quality and even stability problems. This work shows that electrodialysis desalination systems can be managed as smart loads, that is, they can contribute to the power balance and voltage regulation of the microgrid without neglecting its main function of water desalination. For this, a model of multiple inputs and multiple outputs for a desalination system is proposed where the variables to control are the treated water concentration and the active and reactive powers demanded by the desalination system. Based on this model, a control law is proposed that allows to face the complexity of the non-linear system in a simple and precise way. The proposed control guarantees the low salt concentration of the drinking water and favors the energy balance of the microgrid, allowing better control of the power quality and greater penetration of renewable energy generation
Integrated Methodology for Physical and Economic Assessment of Coastal Interventions Impacts
Get PDFDue to economic, environmental, and social interest of coastal areas, together with their erosion problems, different coastal management strategies can be considered, with different physical (shoreline evolution) and economic (net present value, ratio benefit-cost, break-even point) consequences and impacts. Therefore, this work presents an integrated methodology that aims to compare and discuss the most promising coastal intervention scenarios to mitigate erosion problems and climate change effects, considering costs and benefits related to each intervention. The proposed methodology takes a step forward in assessing the coastal erosion mitigation strategies, incorporating three well-defined and sequential stages: shoreline evolution in a medium-term perspective; structures pre-design; and a cost-benefit assessment. To show the relevance of the methodology, a hypothetic case study and several intervention scenarios were assessed. In order to mitigate costal erosion two different situations were analyzed: the reference scenario and the intervention scenarios. 34 intervention scenarios were proposed and evaluated to mitigate the erosion verified. Depending on the parameter considered (reduce erosion areas, protect the full extension of urban waterfronts, improve the economic performance of the intervention by increasing the net present value, the benefit-cost ratio or decreasing the break-even time), best results are obtained for different scenarios. The definition of the best option for coastal erosion mitigation is complex and depends on the main goal defined for the intervention. In conclusion, costs and benefits analysis are demanded and it is considered that the proposed methodology allows choosing better physical and economic options for future coastal interventions, helping decision-making processes related to coastal management
Effect of Cocoa Powder, Banana Pulp and Bambara Nut Inclusion on Nutritional and Sensory Acceptability of Yoghurt
Get PDFThis study was to investigate the effect of utilizing milk powder with addition of Cocoa powder, Banana pulp and Bambara nut extract for the production of functional yoghurt. The yoghurt samples were produced by 10% inclusion of each of the food item into reconstituted skimmed milk powder, inoculated with starter culture (streptococcus.thermophilus and Lactobacillus. Bulgaricus) and allowed to ferment for 9hr. The nutritional properties (Proximate, Brix, PH, Flavonoid, Vitamin C, antioxidant activity) and sensory characteristics (colour, taste, aroma and over all acceptability) were determined. Significant differences (p<0.05) existed among the nutritional and sensory properties of the yogurts. The results showed that the inclusion of used food items improves the Protein, Ash and Energy content of the products. The sample with Cocoa powder had the highest antioxidant activity (2.75mg/100g) which is significantly higher at (p<0.05) than Banana pulp (2.64mg/100), Bambara nut extract (2.44mg/10g) and control (2.25mg/100g) which was the least. The sample with Banana pulp inclusion has highest score (5.70) for taste and overall-acceptability (5.90) using 7-point score ranking and was the most preferred. The microbial load of all the samples were within the limits specified of acceptable counts, making the products safe for consumption as at the time the products were evaluated
Numerical Study of Air-Flow Phenomena Through a Baffled Rectangular Micro-Channel
Get PDFThe aim of this study is to investigate the heat transfer characteristics of turbulent airflow phenomena in a rectangular micro-channel in presence of two plane shaped (type-1) and diamond shaped (type-2) baffles which will help to develop various heat exchanger models. Finite volume method has been used to solve the governing equations and the FLUENT software has been employed to visualize the simulation results. For both the baffles, the profile of flow structure, normalized velocity profile, normalized friction factor and average Nusselt number have been investigated with the variations of Reynolds number ranges between [10,000-50,000]. In terms of fluid flow and heat transfer phenomena, it has been found that in the presence of diamond shaped baffles (type-2) are more convenient than plane shaped baffles
Extraction of Kaempferitrin and Astragalin from Justicia Spicigera by Supercritical Fluid Extraction and Its Comparison with Conventional Extraction
Get PDFA study of supercritical fluid CO2 extraction of kaempferitrin (KM) and astragalin (KG) from Justicia spicigera (muicle) was conducted. A 33 Box-Behnken design was used to analyze the effects of pressure (200-300 bar), temperature (40-60° C), and co-solvent flow rate (0.5-1.0 mL/min). The highest KM and KG concentration were achieved at a pressure of 300 bar, a temperature of 60° C, and co-solvent flow rate of 1.0 mL/min (ethanol 99.5 %), with a constant CO2 flow rate of 5 mL/min and extraction time of 180 min. Under these conditions, the experimental values for KM and KG (115.08±2.81 and 56.63±9.02 mg/100 g of dry powder, respectively) were similar to those calculated by the models (109.0 and 44.07 mg/100 g of dry powder, respectively). The use of 70 % ethanol as co-solvent in the supercritical extraction process considerably improved the yields of KM and KG (562.71±156.85 and 79.90±18.03 mg/100 g of dry powder, respectively) compared to the 99.5 % ethanol extractions. The conventional extraction showed the highest yields of KM and KG (574.20±65.10 and 113.10±15.06 mg/100 g of dry powder, respectively) at 70° C and extraction time of 120 min. Adequate yields were achieved of KM and KG by supercritical fluid extraction compared with conventional extraction (98 and 70 %, respectively); therefore supercritical fluid extract of J. spicigera could be used in the development of functional foods, as well as its possible use in traditional medicine by the health professionals
Porous Sulfonated PVA Microspheres for Controlled Molecules Delivery: A Methylene Blue Study
Get PDF Functionalized PVA microspheres are commonly used as drug carriers in the fields of pharmacy and medicine. With this aim, we obtained and test novel PVA-PVAc-AMPS sulfonated microspheres by free radical suspension polymerization of vinyl acetate (VAc) and 2-acrylamido-2-methyl-1-propanesulfonic sodium salt acid (AMPS), followed by saponification. The microspheres exhibited a porous core-shell structure with excellent sphericity, a mean size of 171 µm, and elasticity modulus comparable with commercial particles currently used in medical applications. Methylene blue (MB) which has shown similar adherence properties as the cytostatic drug doxorubicin was used as a model drug to study the drug loading/release characteristics of the sulfonated microspheres prepared in this work. 20.7 mg g-1 MB per gram of microspheres was the maximum adsorption capacity in two hours using UV-Vis absorption spectroscopy. The experimental data on adsorption were well described by the pseudo-second order kinetic model. The in vitro release profile of loaded MB microspheres showed rapid desorption in the first hour followed by slower MB release, reaching 8.6% elution at four hours. The diffusion process was found to be dominant in the MB desorption from the PVA-PVAc-AMPS microspheres
Protein Extractability and Thermally Induced Gelation Properties of African Locust Bean Proteins (Parkia biglobosa Jacq. R.Br)
Get PDFAfrican locust bean (AfLB) protein isolates could be an interesting alternative to the use of soy as an ingredient for the development of new protein-rich products. From AfLB seed flour, the protein extractability yields by aqueous extraction were determined as a function of pH and ionic strength. Then thermally induced gelation of various protein suspensions relating to protein concentration was studied. The most critical factors affecting extractability were the pH and the presence of fat. As a function of the extraction process, the extraction yield of protein from AfLB flour ranged from 30 to 65%. Two major fractions of proteins detected in AfLB seeds were albumins and globulins, comprising four families: legume-like protein, vicilin-like proteins, convicilin, and albumins. The globulin isolate had the lowest solubility at pH 3.5-4 and the highest at pH 8-10. The solubility of albumin isolate was lightly affected by pH and ionic strength. At pH 7, the minimum protein concentration for thermal gel formation ranged from 55 to 120 g/L as function purified state of proteins. The less purified extract with a simpler process made it possible to obtain a gel needing a lower protein concentration. This last way seems promising to the development of new foods based on African locust bean flour