Influence of Spray Drying Conditions on Physicochemical Properties of Chicken Meat Powder

The influence of spray-drying conditions on the physicochemical properties of chicken meat hydrolysate powder was studied in this work. Enzymatic reaction, using Alcalase® (Novozymes, Bagsvaerd, Denmark), was carried out at 52.5°C, 4.2 g enzyme/100 g protein, and pH of 8.0 to obtain protein hydrolysate. The spray drying was carried out on a laboratory spray dryer and maltodextrin 10DE was used as carrier agent. A central composite rotatable design was used to evaluate the effect of the independent variables inlet air temperature, feed flow, and maltodextrin concentration on the responses powder moisture content, bulk density, mean particle diameter, and hygroscopicity. All variables had a significant effect on the properties and morphology of protein hydrolysate powder.     

Influence of Processing Conditions on the Physicochemical Properties and Shelf-Life of Spray-Dried Palm Sugar (Arenga pinnata) Powder

The influence of spray-drying conditions on some physicochemical properties of palm-sugar powder ( Arenga pinnata ) was studied. Twenty tests were carried out according to a central composite design. Independent variables were: inlet temperature (150–190°C), feed flow rate (9–21 g/min), and maltodextrin concentration (14–25%). Process yield, hygroscopicity, and outlet temperature were analyzed as responses. Results revealed that increasing inlet temperature resulted in higher process yield and outlet temperature and a lower hygroscopicity. Similarly, higher inlet temperature led to lower moisture content, dissolution rate, and total phenolic content of the powder. Conversely, the feed flow rate negatively influenced process yield and hygroscopicity, and positively influenced moisture content. Moreover, maltodextrin exhibited negative influence on process yield and hygroscopicity, respectively. Moreover, storage (30°C, six months) led to noticeable losses in flowability and wettability. Powder morphology was also influenced by the inlet temperature. Lower inlet temperature resulted in particles with shrivelled surfaces while higher temperature produced a greater number of larger particles with smooth surfaces.     

Impact of Spray-Drying Process Parameters on Dairy Powder Surface Composition and Properties

To design dairy powder properties according to their future use, it is necessary to know how to identify the main process parameters that influence the drying mechanisms and to optimize them on the basis of the desired powder properties. The impacts of atomization process parameters on powder physicochemical properties and surface composition were investigated and correlated. The analytical results permitted us to sort the produced powders into groups according to their dependency to process parameters. This study shows the feasibility of developing a model for the prediction of the physicochemical properties of dairy powders via a reverse engineering approach.     

Influence of a Lipid Phase on the Physical Properties of Spray‐Dried Maltodextrin Powders

Maltodextrin powders containing 5, 10, 15, 20 and 25 % from three different palm oil fractions were produced by spray‐drying emulsions with 30 wt % total solids content. The effect of the lipid phase on the characteristics of the particles was evaluated. Oilless spray‐dried particles presented a smaller average size and reduced wettability as compared to the commercial product. An increase in fat content resulted in a decrease in true density while the Hausner Ratio and average diameter of the particles increased. The powders containing palm olefins (melting points, 14 °C and 18 °C) were stickier than the product containing stearin (melting point, 51 °C).     

Physicochemical Characteristics of Date Powder Produced in a Pilot-Scale Spray Dryer

Date fruit is a good source of bioactive compounds and natural sugar. It has the potential to be utilized as a substitute for added sugar. Although several forms of dates—such as fresh dates, date paste, and date syrup—are available in the market and used for different applications, free-flow date powder would be highly beneficial in improving shelf-life, ease of handling, and blendability with various foods prepared domestically and in industry. The objective of this study was to produce date powder in a pilot-scale spray dryer and determine its physicochemical qualities. Date powder was produced at eight processing conditions (2 carrier agents (maltodextrin (MD) and gum arabic (GA) × 2 inlet air temperature (150°C and 170°C) × 2 feedstock flow rates (25 ml/min and 40 ml/min)). To the carrier agent was added at 0.4 kg per 1.0 kg of date fruits (dry weight basis), and the feedstock to the spray dryer was prepared at 20% concentration. Date powder was obtained in all eight treatments. Color (L*a*b* values), moisture content, bulk density, wettability, solubility index, hygroscopicity, microstructure analysis (using scanning electron microscope (SEM)), and total phenolic compounds were determined for the spray-dried date powder. The physicochemical characteristics of date powder varied significantly with respect to the processing conditions. Although physical properties of date powder were significantly affected by the carrier agent, there was no difference in total phenolic compounds between date powders produced with MD and GA. An SEM study revealed that date powder produced with MD had smooth, regular-shaped spherical particles but with severe agglomeration. Date powder with GA had relatively smaller particles of irregular sphere with dented surfaces.     

Effects of the Physicochemical Properties of Metronidazole-Corn Starch Mixtures on the Parameters of the Pellets in the Wet-Granulation Method

Whether the surface free energy of a powder mixture (metronidazole-corn starch) depends on the proportions of the components and how the forces of cohesion and adhesion between the particles affect their interactions as functions of the proportions of the components were investigated. Pellets were produced from the powder mixtures. The interactions between the powder mixtures and the binding agent were first investigated on the basis of the spreading coefficients (S) calculated from the surface free energy. The mechanical properties of the pellets produced were predicted from the S values. Pellet parameters were evaluated as functions of the corn starch content. The overall aim was to investigate the role of the surface free energy of two-component powder compositions in pellet production. In contrast with predictions from the S values, pellets with a more porous and loose texture and with unfavourable mechanical properties can be produced as the S values are increased.     

Application of Design of Experiments and Multilayer Perceptron Neural Network in Optimization of the Spray-Drying Process

The aim of this study was to investigate the effect of changing spray-drying parameters on the production of a naratriptan/maltodextrin/lactose composite, as well as to evaluate the application of design of experiments and multilayer perceptron (MLP) neural network in studying the spray-drying process. The system was spray dried as an aqueous solution using a Büchi 290-Mini Spray Dryer (Büchi Laboratoriums-Technik AG, Switzerland). A 2^4?1 factorial design study was undertaken to select the spray-drying processing variables that significantly affect the production yield, outlet air temperature, and residual moisture content. The process parameters studied were inlet air temperature, pump speed, aspirator setting (drying air flow rate), and feed concentration. After performing this screening study, three process parameters, pump speed, inlet air temperature, and feed concentration, were selected for further analysis, applying a central composite design and artificial neural network. Overall, the parameter that had the greatest influence on each investigated response was pump speed. It significantly influenced yield, moisture content, and particle size. Interaction between inlet air temperature and feed concentration was the only statistically significant interaction that influenced the moisture content. Particle size was mostly influenced by feed concentration as well as by a pump speed. A multilayer perceptron was the type of artificial neural network applied. The selected MLP structure had three layers: the first layer had three input units, the second layer had three hidden units, and the third layer had four output units. The selected MLP was trained through 10,000 epochs. Design of experiments using response surface methodology allows insight into interactions between variables, and an artificial neural network provides better prediction potential, enabling simultaneously determination of several outputs. Design of experiments and artificial neural network proved to be useful tool for optimization of the spray-drying process, where a design space for achieving the best process yields and optimum particle characteristics was established. There is a possibility that this conclusion can be drawn for other maltodextrin/lactose systems with other drug substances or for other similar spray-dried systems (the feedstock type is a carbohydrate-based aqueous solution). In future work, this will be tested with other materials.     

Effect of Additives on Quality of Spray-Dried Fructooligosaccharide Powder

Fructooligosaccharide (FOS) finds its applications as an alternative sweetener in powder form. The effect of different process parameters (feed concentration, feed flow rate, inlet air temperature), different additives (maltodextrin, gums, starch), and anticaking agents (in different combinations and concentrations) during spray drying were investigated. FOS solution with 2% magnesium oxide as an additive gave a maximum powder yield (43% w/w), and the spray-dried powder size was fine and the texture was like talcum powder. Flow properties and microbial analysis were found to be satisfactory. The addition of anticaking agents did not have a significant effect either on the color of the powder or on FOS content, indicating good quality of the powder with respect to flowability, microbial load, and texture.     

煤矸石粉填充聚丙烯复合材料的性能

研究了纯煤矸石粉及用表面活性剂处理或加入界面改性剂的煤矸石粉对两种聚丙烯(PP)的力学性能及加工流动性能的影响。结果表明：随着煤矸石粉用量的增加，PP填充复合材料的拉伸断裂伸长率和冲击强度下降．但拉伸屈服强度和加工流动性变化不大；煤矸石粉经硬脂酸处理后对复合材料的断裂伸长率、冲击韧性及加工性能有一定的改善作用；马来酸酐接枝聚丙烯能够明显提高复合材料的拉伸强度和冲击韧性。     

Thermodynamic and Quality Properties of Lemon Juice Powder as Affected by Maltodextrin and Arabic Gum

Sorption isotherms of lemon juice (LE) powders with and without additives—18% maltodextrin (MA) or 18% gum Arabic (GA)—were determined at 20-50°C. Addition of additives was shown to affect the isotherms in such a way that, at the same water activity, samples LE + GA and LE + MA presented lower equilibrium moisture content and were not so affected by varying temperature. The net isosteric heats of sorption of juice powders with additives were higher (less negative) than those of lemon juice powders, suggesting that there are more active polar sites in the product without addition of GA or MA. In general, the quality properties decreased with the addition of maltodextrin and gum arabic and it was obtained similar values for LE + GA and LE + MA.     

Influence of Processing Conditions on the Physicochemical Properties of Complex Fat Systems

Three blends of soybean oil (SBO), coconut oil (CO), and palm stearin (PS) were crystallized at different shear rates (100 and 1,000 rpm) and processing temperatures (low and high) in a scraped surface heat exchanger. The SBO/CO/PS proportions (w/w) tested were 50/0/50 %, 33/33/33 %, and 16.7/16.7/66.6 %. The physicochemical properties of the blends were analyzed by differential scanning calorimetry, texture analysis, microscopy, and the released oil (Ro) technique. The blends crystallized at 100 rpm developed two endotherms, which were associated with β and co-crystallized β′. In contrast, only the β′ polymorph was observed in blends processed at 1,000 rpm. After 28 days, the presence of β crystals and medium-chain TAG in the blends appeared to stimulate a transition of phase from β′ to β. In general, the hardness of the blends was directly related to the concentration of PS. The systems that were crystallized at 1,000 rpm demonstrated higher hardness, adhesiveness, and crystalline stability than those crystallized at 100 rpm. At both processing temperatures investigated, the blends with the highest Ro and permeability were obtained at 1,000 rpm. These characteristics were associated with the agglomeration of saturated TAG and were promoted by the initial crystallization conditions and migration of TAG during storage. At shear rates of 1,000 rpm and a PS concentration range of 50–66.6 %, the Ro of the blends was 2–10 % with a lower solid fraction, an important signal of good stability.     

Physical and Mechanical Properties of Iron Powder Filled Polystyrene Composites

This article reports on an experimental study of the physical and mechanical properties of Polystyrene (PS) and Fe-PS polymer composites containing 5, 10, and 15 vol.% of Fe powder. After mixing Fe powder and PS in a twin-screw extruder, an injection-molding machine was used to prepare unfilled PS and Fe-PS polymer composite samples. After that, the material properties were experimentally determined for each sample. The investigated material properties included the modulus of elasticity, yield and tensile strength, % elongation, Izod impact strength (notched), hardness (Shore D), melt flow index (MFI), heat deflection temperature (HDT), Vicat softening point, and glass transition temperature (T _g ). The results indicated that, compared to the unfilled PS, an addition of Fe into PS decreases the yield and tensile strength, % elongation, and Izod impact strength. Furthermore, it was determined that the Fe particles increase the modulus of elasticity, hardness, MFI, Vicat softening point, and HDT values.     

Influence of Carrier Agents on the Physicochemical Properties of Mussel Protein Hydrolysate Powder

The objective of this work was to evaluate the influence of carrier agents, maltodextrin 10 dextrose equivalent (DE) and gum arabic, on the physicochemical properties of mussel meat protein hydrolysate powder produced by spray drying. Hydrolysate was obtained by enzymatic hydrolysis using Protamex (Novozymes, Bagsvaerd, Denmark) and was carried out at 51°C, 4.5 g enzyme/100 g protein, and pH 6.85. The hydrolysate, without and with 15 and 30% of carrier agent, was spray dried at 180°C inlet air temperature and 0.8 L/h feed flow rate. Moisture content, hygroscopicity, particle size, glass transition temperature, morphology, antioxidant capacity, and volatile loss of powders were evaluated. Powder moisture content decreased with the increase in carrier agent concentration. Glass transition temperature increased with carrier agent addition and consequently powder hygroscopicity was reduced, increasing its physical stability. Higher feed solution viscosity was obtained for 30% of maltodextrin and 15 and 30% of gum arabic. The particles obtained from these solution presented a greater number of dents and larger particle size. The use of carrier agents reduced volatile loss and preserved the powder's antioxidant capacity.     

Thermodynamic and Quality Properties of Lemon Juice Powder as Affected by Maltodextrin and Arabic Gum

Sorption isotherms of lemon juice (LE) powders with and without additives—18% maltodextrin (MA) or 18% gum Arabic (GA)—were determined at 20–50°C. Addition of additives was shown to affect the isotherms in such a way that, at the same water activity, samples LE + GA and LE + MA presented lower equilibrium moisture content and were not so affected by varying temperature. The net isosteric heats of sorption of juice powders with additives were higher (less negative) than those of lemon juice powders, suggesting that there are more active polar sites in the product without addition of GA or MA. In general, the quality properties decreased with the addition of maltodextrin and gum arabic and it was obtained similar values for LE + GA and LE + MA.     

工艺条件对玻纤增强ABS材料力学性能的影响

通过对30％玻纤增强ABS材料微观形态观察和分析，探寻了加工工艺条件和加入马来酸酐接枝ABS对材料力学性能的影响，结果表明，加入马来酸酐接枝ABS可明显改善基体材料与玻纤的粘结状况，使力学性能得到较大幅度的变化，加工温度的提高和适当的螺杆转速可提高玻纤在基体中的分散性，尽管玻纤分散性较好的材料其玻纤含量较低，玻纤长度较短，但仍使力学性能得到改善。     

联苯型聚酰亚胺模塑粉亚胺化工艺及其力学性能的研究

采用红外光谱分析谱图中725cm^-1处特征峰,表征了联苯型聚酰亚胺模塑粉在不同亚胺化工艺下的亚胺化率。结果表明：温度是控制亚胺化率大小的关键因素,模塑粉的亚胺化程度越高,聚酰亚胺材料的力学性能越好。     

改性煤矸石粉/SBS复合材料的制备及性能研究

采用双辊开炼机和平板硫化机高压制样的方法制备了煤矸石粉/SBS复合材料体系,运用SEM、DSC、TG对复合材料的断面形貌和热性能进行了分析,同时对复合材料的力学性能进行考察。结果表明,表面改性的煤矸石粉在SBS体系中与弹性体充分结合,断面产生了大量的网状结构,进一步提高了材料的拉伸强度、断裂伸长率和热稳定性,硬度增加幅度较小。     

坩埚材料对银浆玻璃粉物化性能的影响

采用了高温熔融法制备了Bi2 O3-B2 O3-ZnO-Al2 O3-SiO2系银浆玻璃玻璃粉,添加少量CeO2作稳定剂,分别采用铂金坩埚、石英坩埚、刚玉坩埚在1100℃条件下熔制,系统研究了在不同坩埚熔制时对该系玻璃的玻璃化程度、热学性能及化学稳定性的影响.结果表明:在添加CeO2稳定剂的前提下,该系玻璃在铂金坩埚、石英坩埚、刚玉坩埚中均能熔制出均匀透明玻璃.在铂金坩埚中熔制时,玻璃的玻璃化程度较高.在石英坩埚中熔制时,较多的SiO2融入该系玻璃粉内,提高了其玻璃化转变温度,但其膨胀系数明显降低,其热稳定性与化学稳定性也有大幅度提高.在刚玉坩埚中熔制时,刚玉坩埚中少量Al2 O3融入玻璃粉内,提高了该系玻璃粉的玻璃化程度,对其热稳定性与化学稳定性的提高也有一定的促进作用.     

Effect of Maltodextrin Addition during Spray Drying of Tomato Pulp in Dehumidified Air: II. Powder Properties

This work investigates the effect of maltodextrin addition on the main powder properties during spray drying of tomato pulp in dehumidified air. A pilot-scale spray dryer was employed for the spray-drying process. The modification made to the original design consisted in connecting the spray dryer inlet air intake to an absorption air dryer. 21 DE, 12 DE, and 6 DE maltodextrins were used as drying agents. Tomato pulp was spray dried at inlet air temperatures of 130, 140, and 150°C and (tomato pulp solids)/(maltodextrin solids) ratios of 4.00, 1.00, and 0.25. The tomato powders were analyzed for rheological properties, moisture content, bulk density, solubility, hygroscopicity, and degree of caking. It was found that maltodextrin addition improved powder hygroscopicity, caking, and solubility, whereas it deteriorated slightly its moisture content and density. In addition, analysis of experimental data yielded correlations between powder properties and the above-mentioned variable operating conditions. Regression analysis was used to fit a full second-order polynomial, reduced second-order polynomials, and linear models to the data of each of the properties evaluated. F values for all reduced and linear models with an R ² ≥ 0.70 were calculated to determine if the models could be used in place of full second-order polynomials.