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D-optimal Mixture Design for Optimized Microencapsulation of Vitamin A Palmitate and Its Characterizations
Get PDFFood fortification is an effective intervention strategy for combating micronutrient deficiencies. Vitamin A can be fortified in a wide range of food vehicles. In this research work, vitamin A in the form of palmitate (VAP) have been microencapsulated by emulsion technology intended for fortification purposes. D-optimal mixture design approach was applied for optimizing the experimental process parameters. Detailed physico-chemical –thermal characterization of the optimized VAP emulsion was done. VAP content was kept constant as per fortification limit. Desirability ramp function graphs and lab experimentations showed maltodextrin (2.5-2.7), OSA starch (1.5-1.6), Tween 80 (1.5-1.7), Span 40 (2.0-2.2) in terms of percentages gave encapsulation efficiency in the range of 98.2-98.8. The optimized VAP emulsion showed particle size in the range of 940-942 nm, polydispersity index 0.41, zeta potential (ζ) value ranging from -31.25 to -32.01 mv; viscosity and interfacial tension was determined to be 1.561±0.03 mPaS and 22.6 mNm−1 respectively. Low temperature DSC studies (-5ºC to 90ºC) of VAP emulsion showed sharp endothermic peaks of vitamin A that disappeared with further elevation in temperature and some flat thermograms of other excipients. The vitamin A content in VAP emulsion was determined to be 88.45±0.03%, the content being reduced to 86.01±0.04% after storage under accelerated conditions (75ºC, 80% RH). The formulated VAP emulsion showed high encapsulation efficiency and significant stability of the emulsion system
Bioactive Gelatin-based Date By-Product for Packaging Applications: Physico-Chemical and Biological Characterization
Get PDF Biodegradable films from gelatin (Gn) with various date by-product (DBP) concentrations (1, 2, 3 and 4 wt %) were prepared. Elaborated films were examined in terms of physical properties (thickness, density, water solubility, water content, degree of swelling, color), and antimicrobial properties (Escherichia coli and Staphylcoccus aureus). Adding the highest concentration of DBP (4%), resulted an increase in the WHC of film as compared with control film. Moreover, the incorporation of 1% DBP reduced the moisture level of Gn based composite films as compared with the control film. Furthermore, Film with 4% of DBP had the lowest solubility which reached 39.39%. Incorporation of DBP from 1 to 4% showed decrease of L- and a-values. The active Gn-DBP 1% showed less lightness as compared to Gn-DBP 3%. The incorporation of DBP into film-forming solutions led to increased opaqueness for all gelatin-based composite films. The calculated opacity value was inversely proportional to transparency. Moreover, the Active Gn-DBP 1% and 2% film presented effective antibacterial activity against bacteria such as Staphylococcus aureus and Escherichia coli. The results showed an enhancement in the biodegradability of Gn-DBP films in moist soil. The results reveal the benefits of date by-products incorporated into gelatin based films as a potential material for active food packaging. 
Hydroxyapatite Humidifier Vibrator Housing Fabrication and Characteristics
Get PDFThe humidifier vibrator housing is difficult to clean and prone to contamination due to its metallic material. To overcome these shortcomings, the humidifier vibrator housing was manufactured using Hydroxyapatite as a raw material. Although hydroxyapatite has excellent antibacterial properties and biocompatibility, it is difficult to manufacture a sintered body due to its weak fracture toughness. Therefore, hydroxyapatite sintered compacts were prepared according to the amount of plasticizer added and their physical properties were compared. The average compressive strength was 395.1 N·mm-2 at 8 % of the amount of added plasticizer, and the average bending strength was 61.8 N·mm-2 at 6 % of the amount of added plasticizer. The hydroxyapatite sintered compact showed the effect of inhibiting the production of bacteria regardless of the amount of plasticizer added. As a result of this physical property study, it was possible to develop a humidifier vibrator housing with excellent antibacterial properties and maintaining mechanical strength
Elastic Wave Property of Concrete Decomposed by Steam Pressure Cracking Agent
Get PDFA steam pressure cracking (SPC) agent is a method that can dismantle concrete safely and quickly. In previous studies, the authors showed that the direction of the crack could be controlled by the tensile stress at the induction holes and not by the compressive stress at the SPC hole. We demonstrate that the compression elastic wave changes to a tensile wave when the wave is reflected at the free surface of the induction hole. We also examined the properties of the concrete by developing an elastic wave measuring system that is difficult to break down even in high-temperature, wet, and radiation environment. The elastic wave velocity change in the four concrete types was less than 4%. It was found that the standard deviation value, σ, changed four times. Therefore, it is possible to determine the deterioration of the internal structure of concrete using the standard deviation value σ, which indicates the dispersion of the elastic wave velocity
Correlation of Wine’s Main Components’ Concentration with the Density of Model Aqueous Solutions and Wine Samples
Get PDFDensity is an important physical property, affecting wine mouthfeel, while it can also be used for monitoring alcoholic fermentation in winemaking. Aim of this study was to elucidate the correlation of ethanol, glucose/fructose, glycerol and tartaric acid on the density of model aqueous solutions and Greek wine samples. Various model aqueous solutions were prepared and density was measured at 20 ˚C. Density of dry white and red wine samples was also measured. A linear regression analysis was performed and theoretical fermentation monitoring curves by density measurement were obtained. The resulting models presented a coefficient of determination over 97.3%. Tartaric acid was found to increase density the most, followed by glucose and glycerol, whereas ethanol decreased density. The knowledge of the correlation of the concentration of each wine component with density may be beneficial to quantitative analysis of wine and to optimizing wine mouthfeel
Quality Retention and Inhibition of Thermophiles in Milk Using a Novel 3-Stage Recyclable Batch Pasteurizer
Get PDFMilk quality decline and proliferation of microorganism can be prevented by heat-treatment. This however can denature the nutrients under excessive processing condition. There is therefore a need to selectively apply and evaluate this technology for milk pasteurization. In this research, the performance of a novel 3-stage recyclable batch milk pasteurizer operating at varying temperature (63– 71 °C), stirring speed (15 – 25 rpm) and holding time (15 sec – 30 min) was determined. The equipment has a hot water storage, pasteurization, and cooling tanks, which maintain the temperature of the pasteurized milk sample to 3–5oC. The nutritional quality and the thermophile loads, including Streptococcus, Clostridium, Micrococcus, and Lactobacillus in the sample were determined as performance indices. The results show no significant trace of the thermophiles (p < 0.05) and a high value of the nutritional composition at 63°C, 25 rpm stirring speed and 15 min holding time. The quality of the product decreased progressively with an increase (p < 0.05) in the temperature and speed for all holding time. Thus, the equipment can be used for milk pasteurization with a reduced nutrient denaturation and thermophiles proliferation
On Approach for Prognosis of Influence of Mismatch-induced Stresses on the I–V Characteristics of p-n-junctions Manufactured in a Heterostructure
Get PDFWe consider a nonlinear model for analysis of current-voltage characteristic of a p-n-junction, which was manufactured in the framework of a heterostructure with specific configuration by diffusion or ion implantation. We analyzed the model to obtain dependence of the considered current-voltage characteristic on missmatch-induced stresses in the framework of the heterostructure. We also consider an analytical approach for analysis of mass and heat transport during the considered processes with account their nonlinearity and missmatch induced stresses as well changes of parameters of these in space and time
Design and Development of Domestic Solar Dryer with Comparative Analysis of Nutritional Aspect of Dried Raisins
Get PDFSolar dryer technology is simple and can be implemented by households and small communities due to its simplicity. The suitable design of the absorber/collector is very vital for any solar drying system as the collector efficiency plays a key role in determining the overall system drying efficiency. To study the practical applicability of a developed solar dryer, grapes were dried in the drying chamber of a designed and developed solar dryer and for comparison, in open sunlight. Faster drying was noted for the grapes dried in the unit. The study on nutritional aspects indicated that solar drying process retained the major nutritional components like total sugars, total proteins and total lipids in raisins. The comparison between the solar dried raisins and open sun dried ones showed a higher ash content of 2.71% with solar dried ones and 1.95% in case of open sun dried raisins. The quantity of MUFA content was also affected by the varying drying practices implemented with 10.95% and 7.12% MUFA in solar dried and open sun dried raisins respectively. The drying technique also affects the bacterial load on raisins as observed in our current study with negligible bacterial growth on on solar dried raisins compared to open dried ones
Influence of Substrate Surface Roughness on Synthesized Diamond Films by Flame Combustion on Ti Substrate for Dental Implants
Get PDFThe flame combustion method enables the synthesis of diamonds via acetylene-oxygen gas flame combustion in ambient air, and this method has various advantages over other methods. However, most diamond films synthesized by this method delaminate because of thermal stress during cooling. Titanium (Ti) has recently been utilized as a dental implant in the dental industry. In this study, to improve the strength, wear resistance, and biocompatibility of dental implant surfaces, diamond films were synthesized on a Ti substrate, a dental implant material, by the flame combustion method. Moreover, to obtain high-quality diamond films and achieve good adhesion on the Ti substrate, as a pretreatment of the substrate to prevent delamination, scratch processing, in which a substrate is ground with emery paper in one direction, was performed to roughen the surface. The surface roughness of the Ti substrates was varied by scratching with emery paper of #180, #400, and #1500 grain sizes. According to these results, diamond films were synthesized on the Ti substrate surface by flame combustion. The surface morphology of the synthesized films could be altered by varying the scratching process using emery paper. Delamination of the synthesized films during the scratching process with emery paper #180 (Case A) and #400 (Case B) grain size was completely prevented. However, delamination occurred during the scratching process with a grain size of emery paper #1500 (Case C). To investigate the reason for this result, the surface roughness of the pretreated Ti substrate was observed, and it affected the surface roughness of pretreated Ti substrate affected the surface morphology and delamination of the synthesized diamond films
Optimization of Disinfection Treatment for Shelf Life Extension of Fresh Cut Salad Vegetables
Get PDFIn the present study, disinfectant pre-treatment conditions were optimized for Fresh cut salad vegetables after evaluating bactericidal efficacy of the five different disinfectants viz. Sodium hypochlorite, potassium metabisulfite, citric acid, acetic acid and benzoic acid. Sodium hypochlorite @ 100ppm was selected for disinfectant pretreatment of fresh cut vegetables viz. cucumber, carrot and tomato through physicochemical and microbial analysis. Optimization of pre-treatment conditions viz. temperature, pH and contact time was statistically designed and analyzed using response surface methodology. Numerical optimization of results revealed a temperature of 6.5, 10.0 and 6.5°C; pH 6.0, 7.0 and 7.0; contact time 23.0, 8.0 and 30.0 minutes was found to be optimized for fresh cut cucumber, carrot and tomato disinfectant pretreatment with a desirability level of 94, 94 and 92%, respectively. Shelf life analysis of pre-treated (under optimized conditions) and untreated fresh cut vegetables stored under refrigeration conditions (5-7°C) revealed enhancement in shelf life of treated fresh cut vegetables from 6, 9 and 6 days to 9, 12 and 9 days of fresh cut cucumber, carrot and tomato, respectively. During shelf life period, all physicochemical parameters of pre-treated fresh cut vegetables differed non-significantly along with microbial load under acceptable limits and a good sensory score