Reduced-fat cheddar cheese manufactured using a novel fat removal process

Normally, reduced-fat Cheddar cheese is made by removal of fat from milk prior to cheese making. Typical aged flavor may not develop when 50% reduced-fat Cheddar cheese is produced by this approach. Moreover, the texture of the reduced-fat cheeses produced by the current method may often be hard and rubbery. Previous researchers have demonstrated that aged Cheddar cheese flavor intensity resides in the water-soluble fraction. Therefore, we investigated the feasibility of fat removal after the aging of Cheddar cheese. We hypothesized the typical aged cheese flavor would remain with the cheese following fat removal. A physical process for the removal of fat from full-fat aged Cheddar cheese was developed. The efficiency of fat removal at various temperatures, gravitational forces, and for various durations of applied forces was determined. Temperature had the greatest effect on the removal of fat. Gravitational force and the duration of applied force were less important at higher temperatures. A positive linear relationship between temperature and fat removal was observed from 20 to 33 degrees C. Conditions of 30 degrees C and 23,500 x g for 5 min removed 50% of the fat. The removed fat had some aroma but little or no taste. The fatty acid composition, triglyceride molecular weight distribution, and melting profile of the fat retained in the reduced-fat cheeses were all consistent with a slight increase in the proportion of saturated fat relative to the full-fat cheeses. The process of fat removal decreased the grams of saturated fat per serving of cheese from 6.30 to 3.11 g. The flavor intensity of the reduced-fat cheeses were at least as intense as the full-fat cheeses.     

An atmospheric-pressure plasma process for C2F6 removal

Perfluorocompounds (PFCs) are widely used in the semiconductor industry for plasma etching and chemical vapor deposition (CVD). They are relatively inert gases that intensely absorb infrared radiation and, therefore, aggravate the greenhouse effect. A bench-scale experimental system was designed and constructed to evaluate the effectiveness of C2F6 conversion by using dielectric barrier discharges (DBD) with atmospheric-pressure plasma processing. Experimental results indicated that the removal efficiency of C2F6 increased with applications of higher voltage and frequency. Combined plasma catalysis (CPC) is an innovative way for abatement of PFCs, and experimental results revealed that combining plasma generation with catalysts could effectively enhance C2F6 removal efficiency achieved with DBD. The major products of C2F6 with DBD processing include CO2, COF2, and CO, when O2 was included in the discharge process. Experimental results indicated that as high as 94.5% of C2F6 were removed via CPC at applied voltage of 15 kV, frequency of 240 Hz in the gas stream of N2:Ar:O2:C2F6 = 50:40:10:0.03.     

COD reduction and decolorization of textile effluent using a combined process

This study showed the effectiveness of biological pretreatment involving appropriate microorganisms and suitable support media in a combined process. The combined process consists of biological pretreatment, chemical coagulation and electrochemical oxidation. COD and color were reduced by 95.4% and 98.5% by the combined process, respectively.     

酸溶联用发酵技术脱除大米中镉的工艺优化

为了进一步提高大米中重金属镉的脱除率,快速缓解镉超标大米的利用问题,该文采用酸溶-发酵技术脱除大米中的重金属镉,在前期研究的基础上,固定发酵技术参数,研究酸浸条件对镉脱除率的影响。结果表明：乳酸溶液为大米粉浸泡液,浸泡时间12 h,响应面法优化得到的最佳工艺条件为浸泡温度44.2 ℃,酸液体积分数48%,液料比9∶1（mL∶g）;在最佳工艺条件下处理镉含量为0.647 9 mg/kg的大米,镉的脱除率可达98.01%,与模型预测值相近,且大米粉中镉的残留量远低于国家限量标准。因此,该方法不仅能有效提高大米中重金属镉的脱除率,还能为解决镉超标大米的利用问题提供一定的技术支持。     

Extracting oil from grape seed using a combined wet enzymatic process and pressing

The novel method of wet enzymatic extraction and pressing (WEEP) was used to extract grape seed oil. Low-field nuclear magnetic resonance (LF-NMR) was applied to elucidate the water mobility and distribution of grape seeds during the process. The extraction variables were selected in accordance with a Plackett-Burman (PB) design, and the statistical model was constructed using response surface methodology (RSM). The results revealed that water mobility variations of the samples could be discriminated using the signal amplitude and peak position of the T₂ inversion spectrum. The increase in water content was affected by the time and temperature of the process. The water migration of the samples was monitored clearly and intuitively using magnetic resonance imaging (MRI). Three significant factors out of the six variables (enzyme additive amount, hydrolysis temperature, hydrolysis time, comminution degree, screw speed, squeezed water) were determined. The ideal values of the significant factors were confirmed to be 1% of enzyme additive amount, 60 mesh of comminution degree, and 8% of squeezed water. The residual oil proportion to the initial oil content decreased significantly with parameter optimization (33.24% ± 5.98%) compared with that of the unoptimized parameters (57.79% ± 4.13%).     

亚麻色纺纱高效短流程生产工艺研究与实践

 探讨了亚麻粗纱高效短流程煮漂及染色工艺,通过对粗纱煮漂半制品质量指标、粗纱染色效果及染色纤维的可纺性能测试分析,得出：染色牢度和色泽指标与传统工艺相符、50mm以下短纤维率34.0%,低于传统工艺35.4%;纤维长度平均长度77.5mm,比传统工艺提高了11.3mm,纤维长度整齐度较好,符合后道纺纱要求。探讨的新工艺与传统工艺相比减少了纺纱厂的烘干、包装、染色前的络筒、染色时的预处理工序,纺厂到染厂的运输、装卸等环节,提高了生产效率,减少水耗、能耗和污水处理的压力。     

Development of a kinetic model for the NOx reduction process by potassium-containing coal pellets

A four step kinetic model was developed to describe the NOx reduction process by potassium containing coal-pellets. The relevance and significance of the different steps considered in the model as well as the considerations assumed to introduce the equations associated to this model were properly discussed. The simulation both of the NOx reduction and carbon conversion evolution shows good agreement with the experimental data obtained throughout lifetime tests at 350 degrees C for samples with different potassium contents. The set of parameters predicted by the kinetic model have physical significance and are helpful in explaining the different behavior exhibited by the samples. Some of these parameters can be correlated with different features of the samples. The potassium loading influences mainly on the kinetic rate constant governing the NOx chemisorption step, thus explaining the increase in selectivity with the catalyst content exhibited by this type of samples.     

Investigations into the stabilization of a volatile aroma compound using a combined emulsification and spray drying process

The aromatic compound 3-methylbutyraldehyde (3-mba) was stabilized using a combined emulsification (W₁/O/W₂) and spray drying process. The process suitability and the encapsulation properties of eight materials were evaluated. Whey protein concentrate (WPC), sodium octenyl succinate modified starch (modified starch 1), maltodextrin, and gum Arabic (GA) were found to be the best process-adapted microencapsulation materials. These materials were chosen for further experiments in which the influence of the solids content on flavor intensity and flavor retention during storage were determined. The amount of encapsulated 3-mba increased with increasing solids content from 40–50% using WPC, modified starch 1, and maltodextrin. Microcapsules with GA reached the maximum value of encapsulated 3-mba at 45% solids. After 11 days of storage, flavor retention decreased in the following order: GA > modified starch 1 > WPC ∼ maltodextrin. Finally, the spray drying process was optimized by design of experiments (DoE). The optimized parameters were a feed temperature of 40 °C, a dry mass in W₂ of 60%, and an amount of W₁/O of 40% using modified starch 1.     

Purifying salmon oil using adsorption,neutralization, and a combined neutralization and adsorption process

The performance of activated earth and/or chitosan as an adsorbent to remove free fatty acids (FFA) and peroxides from the unpurified salmon oil was evaluated. The unpurified salmon oil was purified using three methods included activated earth adsorption process, neutralization process, and combined neutralization and activated earth adsorption processes. The purified salmon oil samples were evaluated for free fatty acids (FFA), peroxide values (PV), minerals, color, tocopherols, moisture content, insoluble impurities, and water activity. Neither chitosan nor the activated earth adsorption process was effective in removing FFA from the salmon oil. Neutralized oil had a higher intraparticular diffusion coefficient than the unpurified salmon oil for adsorbing peroxides. FFA of unpurified salmon oil was 3.5% and was significantly reduced (P < 0.05) to 0.12% by neutralization. No significant reduction of tocopherols content of the oil was observed in any of the three purification processes. After the adsorption processes, PV of neutralized oil had decreased from 4.75 to 2.90 mmol/kg. All three purification processes increased the lightness (L^∗) and decreased the redness (a^∗) and reduced mineral, insoluble impurities, moisture content, and water activity of the salmon oil. This study demonstrated that the combined process was more effective in reducing FFA, peroxides, and moisture content than either the activated earth adsorption or neutralization purification process alone.     

Fabrication of catalytic membranes for the treatment of drinking water using combined ozonation and ultrafiltration

The removal of disinfection byproducts and their precursors was investigated using a combined ozonation-ultrafiltration system. A commercial membrane was coated 20 or 40 times with iron oxide nanoparticles (4-6 nm in diameter). With this membrane, the concentration of dissolved organic carbon was reduced by >85% and the concentrations of simulated distribution system total trihalomethanes and simulated distribution system halo acetic acids decreased by up to 90% and 85%, respectively. When the coated membrane was used, the concentrations of aldehydes, ketones, and ketoacids in the permeate were reduced by >50% as compared to that obtained with the uncoated membranes. Hydroxyl or other radicals produced at the iron oxide coated membrane surface as a result of ozone decomposition are believed to have enhanced the degradation of the natural organic matter, thereby reducing the concentration of disinfection byproducts. While increasing the number of times the membrane was coated from 20 to 40 did not significantly reduce the concentrations of most of the parameters measured, it did result in a significant decrease in the concentrations of ozonation byproducts. Increasing the sintering temperature from 500 to 900 degrees C also resulted in an improvement in the removal of the ozonation byproducts.     

Evaluation of microbial reduction of Fe(III)EDTA in a chemical absorption-biological reduction integrated NOx removal system

A chemical absorption-biological reduction integrated process can be used to remove nitrogen oxides (NOx) from flue gas. In such a process, nitric oxide (NO) can be effectively absorbed by the ferrous chelate of ethylenediaminetetraacetate (Fe(II)EDTA) to form Fe(II)EDTA-NO, which can be biologically regenerated by denitrifying bacteria. However, in the course of these processes, part of the Fe(II)EDTA is also oxidized to Fe(III)EDTA. The reduction of Fe(III)EDTA to Fe(II)EDTA depends on the activity of iron-reducing bacteria in the system. Therefore, the effectiveness of the system relies on how to effectively bioreduce Fe(III)EDTA and Fe(II)EDTA-NO in the system. In this paper, a strain identified as Escherichia coli FR-2 (iron-reducing bacterium) was used to investigate the reduction rate of Fe(III)EDTA. The experimental results indicate that Fe(III)EDTA-NO and Fe(II)EDTA in the system can inhibit both the FR-2 cell growth and thus affect the Fe(III)EDTA reduction. The FR-2 cell growth rate and Fe(III)EDTA reduction rate decreased with increasing Fe(II)EDTA-NO and Fe(II)EDTA concentration in the solution. When the concentration of Fe(II)EDTA-NO reached 3.7 mM, the FR-2 cell growth almost stopped. A mathematical model was developed to explain the cell growth and inhibition kinetics. The predicted results are close to the experimental data and provide a preliminary evaluation of the kinetics of the biologically mediated reactions necessary to regenerate the spent scrubber solution.     

Optimization of peroxidase-catalyzed oxidative coupling process for phenol removal from wastewater using response surface methodology

Hydroxylated aromatic compounds (HACs) are considered to be primary pollutants in a wide variety of industrial wastewaters. Horseradish peroxidase (HRP) is suitable for the removal of these toxic substances. However, development of a mathematical model and optimization of the HRP-based treatment considering the economical issues by novel methods is a necessity. In the present study, optimization of phenol removal from wastewater by horseradish peroxidase (HRP) was carried out using response surface methodology (RSM) and central composite design (CCD). As the initial experimental design, 2(4-1) half-fraction factorial design (H-FFD) is accomplished in triplicate at two levels to select the most significant factors and interactions in the phenol removal procedure. Temperature (degrees C), pH, concentration of enzyme (unit mL(-1)), and H202 (mM) were determined as the most effective independent variables. Finally, a fourfactor-five coded level CCD, 30 runs, was performed in order to fit a second-order polynomial function to the results and calculate the economically optimum conditions of the reaction. The goodness of the model was checked by different criteria including the coefficient of determination (R2 = 0.93), the corresponding analysis of variance ((Pmodel > F) < 0.0001) and parity plot (r = 0.96). These analyses indicated that the fitted model is appropriate for this enzymatic system. With the assumption that the minimum enzyme concentration was 0.26 unit mL(-1), the analysis of the response surface contour and surface plots defined the optimum conditions as follows: pH = 7.12, hydrogen peroxide concentration 1.72 mM, and 10 degrees C. This work improves phenol removal operation economically by applying minimum enzyme concentration and highest removal in comparison with previous studies.     

High-efficiency secretory production of peroxidase C1a using vesicular transport engineering in transgenic tobacco

Horseradish peroxidase isozyme C1a (HRP C1a) is widely used as a reporter enzyme in a variety of detection procedures such as enzyme-linked immunosorbent assay (ELISA) and western blotting. We previously isolated the gene encoding HRP C1a and showed that HRP C1a is at first translated as a preproprotein containing propeptides at its N- and C-termini (N-terminal secretion signal peptide and C-terminal propeptide; CTPP). The signal peptide (sp) is necessary for endoplasmic reticulum (ER) translocation and the CTPP acts as a vacuolar sorting determinant. Furthermore, HRP C1a was secreted into the culture medium from cells expressing the HRP C1a gene without the CTPP region. We optimized the secretory production system of HRP C1a in tobacco plants. To determine a suitable signal peptide for high-efficient secretion of proteins, three types of sp derived from HRP C1a (C1Psp), beta-D-glucan exohydrolase (GEsp) and 38 kDa peroxidase (38Psp) were compared. GE and 38P are secretory proteins highly accumulated in the culture medium of BY2 cells. The secretion efficiency was increased by 34% and 53% when GEsp and 38Psp was used, respectively. Next, we used a translational enhancer, the 5'-untranslated region of Nicotiana tabacum alcohol dehydrogenase gene (NtADH 5'-UTR). The production of HRP C1a was increased by placing NtADH 5'UTR in front of the ORF in BY2 cells. These results indicate that the localization and expression level of recombinant proteins can be controlled by the use of propeptides and 5'UTR, respectively. Finally, high-efficiency secretory production of the HRP C1a was also achieved in transgenic tobacco.     

DRIFT study on cerium-tungsten/titania catalyst for selective catalytic reduction of NOx with NH3

CeO(2)/TiO(2) and CeO(2)-WO(3)/TiO(2) catalysts prepared by impregnation method assisted with ultrasonic energy were investigated on the selective catalytic reduction (SCR) of NO(x) (NO and NO(2)) by NH(3). The catalytic activity of 10% CeO(2)/TiO(2) (CeTi) was greatly enhanced by the addition of 6% WO(3) in the broad temperature range of 200-500 °C, the promotion mechanism was proposed on basis of the results of in situ diffuse reflectance infrared transform spectroscopy (DRIFT). When NH(3) was introduced into both catalysts preadsorbed with NO + O(2), SCR would not proceed except for the reaction between NO(2) and ammonia. For CeO(2)/TiO(2) catalysts, coordinated NH(3) linked to Lewis acid sites were the main adsorbed ammonia species. When NO + O(2) was introduced, all the ammonia species consumed rapidly, indicating that these species could react with NO(x) effectively. Two different reaction routes, L-H mechanism at low temperature (<200 °C) and E-R mechanism at high temperatures (>200 °C), were presented for SCR reaction over CeO(2)/TiO(2) catalyst. For CeO(2)-WO(3)/TiO(2) catalysts, the Lewis acid sites on Ce(4+) state could be converted to Br?nsted acid sites due to the unsaturated coordination of Ce(n+) and W(n+) ions. When NO + O(2) was introduced, the reaction proceeded more quickly than that on CeO(2)/TiO(2). The reaction route mainly followed E-R mechanism in the temperature range investigated (150-350 °C) over CeO(2)-WO(3)/TiO(2) catalysts. Tungstation was beneficial for the formation of Ce(3+), which would influence the active sites of the catalyst and further change the mechanisms of SCR reaction. In this way, the cooperation of tungstation and the presence of Ce(3+) state resulted in the better activity of CeO(2)-WO(3)/TiO(2) compared to that of CeO(2)/TiO(2).     

Coupling process for plasma protein fractionation using ethanol precipitation and ion exchange chromatography

Blood is one of the most polluting by-products of the meat industries. Technologies have been developed to recover the proteins contained in blood, and in this study, a process coupling chemical precipitation with ion exchange chromatography was developed to separate and purify the main protein fractions of blood plasma. Ethanol was used as the agent for precipitation and Q-HyperD was used to purify the proteins by chromatography. To monitor all the steps and operations, analytical methods of electrophoresis and HPLC were stablished to identify the fractionated proteins. The results show that this process can recover the main plasma proteins with a high degree of purity for use in the pharmaceutical and food industries.     

High-efficiency NO(x) absorption in water using equipment packed with a glass fiber filter

NO(X) absorption in water is quite difficult by comparison with other exhausted gas, such as SO(2), CO(2), and NH(3) because of low solubility of NO(X) in water. We have been developed a NO(X) absorption equipment with a glass fiber filter having high porosity and surface area. When feed NO(X) gas concentration was high, high NO(X) removal efficiency was obtained. This was because the surface area per glass fiber filter volume was about 40 to 600 times higher than for common packing materials. For verification test and industrial application, a high concentration of NO(X) gas (206,000 ppm) produced by a metal dissolution process was treated with a series of two absorption experiments. We can attain 97.6% of NO(X) removal efficiency, and HNO(3) concentration in water was concentrated up to 56.3 wt %. Furthermore, ozone addition to gas and usage of ozone saturated water as an absorbent resulted in complete removal of NO(X) in the gas (up to 120 ppm). This result indicated the importance of aqueous phase oxidation of HNO(2), which produces NO in the gas phase.     

Enhancement of catalytic performance of a metagenome-derived thermophilic oligosaccharide-specific xylanase by binding module removal and random mutagenesis

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Arsenic removal using mesoporous alumina prepared via a templating method

The health threat of arsenic is well-known, and the U.S. EPA recommends the maximum contaminant level to be 0.01 ppm or less for arsenic in drinking water. Therefore, advanced treatment processes are needed for finished water to meet the required regulations. Adsorption is considered to be a less expensive procedure that is safer to handle than precipitation, ion exchange, and membrane filtration. Activated alumina (AA) is the most commonly used adsorbent for the removal of arsenic from aqueous solutions. However, conventional porous solids including AA have ill-defined pore structures and, typically, low adsorption capacities and act in a kinetically slow manner. An ideal adsorbent should have uniformly accessible pores, an interlinked pore system, a high surface area, and physical and/or chemical stability. To meet this requirement, mesoprous alumina (MA) with a wide surface area (307 m2/g) and uniform pore size (3.5 nm) was prepared, and a spongelike interlinked pore system was developed through a post-hydrolysis method. The resulting MA was insoluble and stable within the range of pH 3-7. The maximum uptake of As(V) by MA was found to be 7 times higher [121 mg of As(V)/g and 47 mg of As(III)/ g] than that of conventional AA, and the kinetics of adsorption were also rapid with complete adsorption in less than 5 h as compared to the conventional AA (about 2 d to reach half of the equilibrium value). A desorption study using sodium hydroxide solutions (0.01-1 M) was conducted, and 0.05 M NaOH was found to be the most suitable desorption agent. More than 85% of the arsenic adsorbed to the MA was desorbed in less than 1 h. Several other activated aluminas with different pore properties were also tested. The results show that the surface area of the adsorbents does not greatly influence on the adsorption capacity. In fact, the key factor is a uniform pore size and an interlinked pore system. These studies show that MA with a wide surface area, uniform pore size, and interlinked pore system can be used as an efficient adsorbent for the removal of arsenic.     

Antioxidative and anti-inflammatory activities of Citrus unshiu peel extracts using a combined process of subcritical water extraction and acid hydrolysis

Antioxidant and in vitro anti-inflammatory activities of citrus (Citrus unshiu) peel extracts and their acid hydrolysates were evaluated. Citrus peel extracts were extracted by subcritical water, hot water, and ethanol. Subcritical water extraction led to extract more phenolic compounds than hot water or ethanol extraction. Acid hydrolysis more than doubled the extracts’ total phenolics and flavonoids. Acid hydrolysates showed greater DPPH-radical scavenging activities and antioxidant activities, as assayed by β-carotene bleaching and ferric thiocyanate, than the initial extracts. Anti-inflammatory activities of citrus peel extracts and hydrolysates, determined by the inhibition of hyaluronidase activity, showed that the inhibition activities of hot water and ethanol extracts increased from 2.1 and 1.8% to 37.0 and 18.5%, respectively, upon acid hydrolysis; however, the anti-inflammatory activity of the subcritical water extract was not improved. These results indicated that acid hydrolysis of citrus peel extracts regardless of their extraction methods improved the antioxidative and anti-inflammatory activities.