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Processing Methods (processing + methods)
Selected AbstractsTHE EFFECTS OF THERMAL AND NONTHERMAL PROCESSING METHODS ON APPLE CIDER QUALITY AND CONSUMER ACCEPTABILITYJOURNAL OF FOOD QUALITY, Issue 1 2005LYNN H. CHOI ABSTRACT Due to increased concern about the safety of fruit, vegetable and juice products, the FDA has mandated that these must undergo a 5-log reduction in pathogens. The development of various processing methods for juice products has caused the need to determine the effects of these methods on said products. The effect of thermal pasteurization, UV irradiation and ozone treatment on apple cider quality and consumer acceptability was studied over 21 days. Thermally pasteurized samples were different in color and less preferred in all areas of consumer acceptability. UV-irradiated samples were lower in soluble solids for the first 7 days and showed no significant difference in consumer acceptability. Ozone-treated cider had greater sedimentation, lower sucrose content and a decrease in soluble solids by day 21. UV irradiation allows for a more cost-effective method to produce safe apple cider with minimal quality and consumer acceptability differences. [source] Processing methods for partially encrypted data in multihop Web servicesELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 5 2008Kojiro Nakayama Abstract Message layer security is necessary to ensure the end-to-end security of Web services. To provide confidentiality against the intermediaries along the message path, XML encryption is used to partially encrypt the message. Because the data structure is changed by the partial encryption, the encrypted message is no longer valid with respect to the original schema definition. Thus, problems occur regarding the processing of the schema validation and the data binding by the intermediary. In this paper, we discuss two possible methods to solve these problems. The first method is to transform the original schema definition. The second is to transform the received message. We examined these methods by applying them to demonstration experiment of Web services. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(5): 26, 32, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10112 [source] Are Points the Better Graphics Primitives?COMPUTER GRAPHICS FORUM, Issue 3 2001Markus Gross Since the early days of graphics the computer based representation of three-dimensional geometry has been one of the core research fields. Today, various sophisticated geometric modelling techniques including NURBS or implicit surfaces allow the creation of 3D graphics models with increasingly complex shape. In spite of these methods the triangle has survived over decades as the king of graphics primitives meeting the right balance between descriptive power and computational burden. As a consequence, today's consumer graphics hardware is heavily tailored for high performance triangle processing. In addition, a new generation of geometry processing methods including hierarchical representations, geometric filtering, or feature detection fosters the concept of triangle meshes for graphics modelling. Unlike triangles, points have amazingly been neglected as a graphics primitive. Although being included in APIs since many years, it is only recently that point samples experience a renaissance in computer graphics. Conceptually, points provide a mere discretization of geometry without explicit storage of topology. Thus, point samples reduce the representation to the essentials needed for rendering and enable us to generate highly optimized object representations. Although the loss of topology poses great challenges for graphics processing, the latest generation of algorithms features high performance rendering, point/pixel shading, anisotropic texture mapping, and advanced signal processing of point sampled geometry. This talk will give an overview of how recent research results in the processing of triangles and points are changing our traditional way of thinking of surface representations in computer graphics - and will discuss the question: Are Points the Better Graphics Primitives? [source] A Comparison of Four Mohs Tissue Preparation Methods Using Porcine SkinDERMATOLOGIC SURGERY, Issue 9 2010FRCPC, WILLIAM LEAR MD OBJECTIVE Mohs surgery relies on high-quality, rapid tissue preparation and processing. This study evaluated four currently performed tissue preparation and processing methods for speed of processing and depth of cut into the tissue block to achieve a complete high-quality section. METHODS The following four methods were tested: cryoEMBEDDER, float, heat sink, and slide. Standardized specimens of porcine skin were used to ensure uniformity. We measured the time required for a technician to flatten, embed, and cut to the first complete section of each specimen. Additionally, we measured the depth in microns required to cut into an embedded specimen to achieve a complete section. RESULTS There were advantages and disadvantages of each method, and our findings suggest that the heat sink and float methods are more time efficient but that the slide and cryoEMBEDDER methods require less cutting into the specimen to obtain a complete section. The cryoEMBEDDER device used in this study was loaned by cryoEMBEDDER (Salt Lake City, Utah). [source] Comparison of LiDAR waveform processing methods for very shallow water bathymetry using Raman, near-infrared and green signalsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2010Tristan Allouis Abstract Airborne light detection and ranging (LiDAR) bathymetry appears to be a useful technology for bed topography mapping of non-navigable areas, offering high data density and a high acquisition rate. However, few studies have focused on continental waters, in particular, on very shallow waters (<2,m) where it is difficult to extract the surface and bottom positions that are typically mixed in the green LiDAR signal. This paper proposes two new processing methods for depth extraction based on the use of different LiDAR signals [green, near-infrared (NIR), Raman] of the SHOALS-1000T sensor. They have been tested on a very shallow coastal area (Golfe du Morbihan, France) as an analogy to very shallow rivers. The first method is based on a combination of mathematical and heuristic methods using the green and the NIR LiDAR signals to cross validate the information delivered by each signal. The second method extracts water depths from the Raman signal using statistical methods such as principal components analysis (PCA) and classification and regression tree (CART) analysis. The obtained results are then compared to the reference depths, and the performances of the different methods, as well as their advantages/disadvantages are evaluated. The green/NIR method supplies 42% more points compared to the operator process, with an equivalent mean error (,4·2,cm verusu ,4·5,cm) and a smaller standard deviation (25·3,cm verusu 33·5,cm). The Raman processing method provides very scattered results (standard deviation of 40·3,cm) with the lowest mean error (,3·1,cm) and 40% more points. The minimum detectable depth is also improved by the two presented methods, being around 1,m for the green/NIR approach and 0·5,m for the statistical approach, compared to 1·5,m for the data processed by the operator. Despite its ability to measure other parameters like water temperature, the Raman method needed a large amount of reference data to provide reliable depth measurements, as opposed to the green/NIR method. Copyright © 2010 John Wiley & Sons, Ltd. [source] Novel Nanoparticle-Reinforced Metal Matrix Composites with Enhanced Mechanical PropertiesADVANCED ENGINEERING MATERIALS, Issue 8 2007C. Tjong Abstract This paper summarizes and reviews the state-of-the-art processing methods, structures and mechanical properties of the metal matrix composites reinforced with ceramic nanoparticles. The metal matrices of nanocomposites involved include aluminum and magnesium. The processing approaches for nanocomposites can be classified into ex-situ and in-situ synthesis routes. The ex-situ ceramic nanoparticles are prone to cluster during composite processing and the properties of materials are lower than the theoretical values. Despite the fact of clustering, ex-situ nanocomposites reinforced with very low loading levels of nanoparticles exhibit higher yield strength and creep resistance than their microcomposite counterparts filled with much higher particulate content. Better dispersion of ceramic nanoparticles in metal matrix can be achieved by using appropriate processing techniques. Consequently, improvements in both the mechanical strength and ductility can be obtained readily in aluminum or magnesium by adding ceramic nanoparticles. Similar beneficial enhancements in mechanical properties are observed for the nanocomposites reinforced with in-situ nanoparticles. [source] Electrically Addressable Hybrid Architectures of Zinc Oxide Nanowires Grown on Aligned Carbon NanotubesADVANCED FUNCTIONAL MATERIALS, Issue 15 2010Jong G. Ok Abstract The fabrication and characterization of hybrid architectures of ZnO nanowires (ZNWs) grown on organized carbon nanotubes (CNTs), by a two-step chemical vapor deposition (CVD) process involving CNT growth from a hydrocarbon source followed by ZNW growth using a Zn metal source, is reported. The ZNWs grow uniformly and radially from individual CNTs and CNT bundles, and the aligned morphology of the CNTs is not disturbed by the ZNW growth process. The nucleation and growth of ZnO crystals on CNTs are analyzed in relation to the classical vapor,solid mechanism. Importantly, the CNTs make uniform and distributed electrical contact to the ZNWs, with up to a 1000-fold yield advantage over conventional ZNW growth on a flat substrate. Hybrid ZNW/CNT sheets are fabricated by scalable CVD, rolling, and printing methods; and their electrical properties, which are governed by transport through the anisotropic CNT network, are characterized. Functional interaction between the ZNWs and CNTs is demonstrated by photoconductive behavior and photocurrent generation of the hybrid material under UV illumination. There is significant future opportunity to extend these processing methods to fabricate other functional oxides on CNTs, and to build devices that harness the attractive properties of ZNWs and CNTs with high volumetric efficiency over large areas. [source] Calculation of the wave propagation angle in complex media: application to turning wave simulationsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2009Xiaofeng Jia SUMMARY The wave propagation angle is one of the key factors in seismic processing methods. For the dual-domain propagators, it is sometimes necessary to acquire the wave propagation angle in the space-frequency domain instead of the wavenumber domain or the angle domain. We propose a method dealing with this problem, in which the wavefield gradient is used for the calculation of the wave propagation angle. The wavefield gradient can be directly obtained by either the finite difference approximation or the marching expression of the propagator. This method is not applicable in the case of extremely low frequency due to the comparability between the wavelength and the grid interval. Combined with the superwide-angle one-way propagator, this approach is instrumental in simulating the turning wave, which is hard to be handled by the traditional one-way propagator. Numerical examples show the good performance of the superwide-angle one-way propagator with our approach involved. The turning wave is modelled accurately; as a result, a high-quality image of the overhanging salt flank can be obtained. [source] The effect of elevated CO2 on diel leaf growth cycle, leaf carbohydrate content and canopy growth performance of Populus deltoidesGLOBAL CHANGE BIOLOGY, Issue 8 2005Achim Walter Abstract Image sequence processing methods were applied to study the effect of elevated CO2 on the diel leaf growth cycle for the first time in a dicot plant. Growing leaves of Populus deltoides, in stands maintained under ambient and elevated CO2 for up to 4 years, showed a high degree of heterogeneity and pronounced diel variations of their relative growth rate (RGR) with maxima at dusk. At the beginning of the season, leaf growth did not differ between treatments. At the end of the season, final individual leaf area and total leaf biomass of the canopy was increased in elevated CO2. Increased final leaf area at elevated CO2 was achieved via a prolonged phase of leaf expansion activity and not via larger leaf size upon emergence. The fraction of leaves growing at 30,40% day,1 was increased by a factor of two in the elevated CO2 treatment. A transient minimum of leaf expansion developed during the late afternoon in leaves grown under elevated CO2 as the growing season progressed. During this minimum, leaves grown under elevated CO2 decreased their RGR to 50% of the ambient value. The transient growth minimum in the afternoon was correlated with a transient depletion of glucose (less than 50%) in the growing leaf in elevated CO2, suggesting diversion of glucose to starch or other carbohydrates, making this substrate temporarily unavailable for growth. Increased leaf growth was observed at the end of the night in elevated CO2. Net CO2 exchange and starch concentration of growing leaves was higher in elevated CO2. The extent to which the transient reduction in diel leaf growth might dampen the overall growth response of these trees to elevated CO2 is discussed. [source] Processing of Bulk Metallic GlassADVANCED MATERIALS, Issue 14 2010Jan Schroers Abstract Bulk metallic glass (BMG) formers are multicomponent alloys that vitrify with remarkable ease during solidification. Technological interest in these materials has been generated by their unique properties, which often surpass those of conventional structural materials. The metastable nature of BMGs, however, has imposed a barrier to broad commercial adoption, particularly where the processing requirements of these alloys conflict with conventional metal processing methods. Research on the crystallization of BMG formers has uncovered novel thermoplastic forming (TPF)-based processing opportunities. Unique among metal processing methods, TPF utilizes the dramatic softening exhibited by a BMG as it approaches its glass-transition temperature and decouples the rapid cooling required to form a glass from the forming step. This article reviews crystallization processes in BMG former and summarizes and compares TPF-based processing methods. Finally, an assessment of scientific and technological advancements required for broader commercial utilization of BMGs will be made. [source] Molecular Self-Assembled Monolayers and Multilayers for Organic and Unconventional Inorganic Thin-Film Transistor ApplicationsADVANCED MATERIALS, Issue 14-15 2009Sara A. DiBenedetto Abstract Principal goals in organic thin-film transistor (OTFT) gate dielectric research include achieving: (i) low gate leakage currents and good chemical/thermal stability, (ii) minimized interface trap state densities to maximize charge transport efficiency, (iii) compatibility with both p- and n- channel organic semiconductors, (iv) enhanced capacitance to lower OTFT operating voltages, and (v) efficient fabrication via solution-phase processing methods. In this Review, we focus on a prominent class of alternative gate dielectric materials: self-assembled monolayers (SAMs) and multilayers (SAMTs) of organic molecules having good insulating properties and large capacitance values, requisite properties for addressing these challenges. We first describe the formation and properties of SAMs on various surfaces (metals and oxides), followed by a discussion of fundamental factors governing charge transport through SAMs. The last section focuses on the roles that SAMs and SAMTs play in OTFTs, such as surface treatments, gate dielectrics, and finally as the semiconductor layer in ultra-thin OTFTs. [source] X-ray images for the control of eye formation in cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2009H KRAGGERUD There is demand for non-destructive monitoring of eye formation in cheese during ripening. The objective of this work was to develop a simple method based on existing equipment in the dairy industry. Images were acquired using a conventional, low resolution online X-ray instrument. Image processing methods for detecting eyes of cheese and measuring volume and size distribution were developed. Sufficient detection of overlapping eyes was obtained. Semihard cheese with propionibacteria ripened under different conditions was analysed. The method was found promising for quality control as it will make possible non-destructive monitoring of eye formation of cheese throughout the ripening period. [source] Recent advances in microdevices for electrochemical energy conversion and storageINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6-7 2007Gerardo Jose La O' Abstract The application of silicon microfabrication technologies to electrochemical devices allows reduction of overall device package to potentially increase volumetric power densities. This review first focuses on some exciting developments in microfuel cells, in particular, solid oxide fuel cells (SOFCs) and proton exchange membrane fuel cells (PEMFCs). The emphasis is given to innovative 2D processing methods, novel 2D architectures of microfuel cells, and demonstrated performance in terms of area power densities. Emerging 3D fabrication techniques that are potentially promising to produce 3D electrochemical devices such as 3D cell and stack architectures on the micrometer scale will then be discussed. Lastly this paper highlights some new opportunities in electrode kinetics studies enabled by microfabricated devices,investigation of scaling relationship between microelectrodes and electrochemical responses, which has led to improved fundamental understanding of electrode reactions and rate-limiting steps. Copyright © 2007 John Wiley & Sons, Ltd. [source] Salted and fermented fish processes evaluationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009Cecília Riscado Pombo Summary Fish curing by salting and fermentation is the result of the action of certain enzymes over fresh fish. This study aimed to evaluate and compare three technological processing methods (A, B, C). Coliforms, Escherichia coli, Enterococcus spp., coagulase-positive Staphylococcus, Salmonella spp., total volatile base (TVB), pH, water activity (Wa), sodium chloride and biogenic amines were evaluated. A significant difference in histamine production (P < 0.05) was observed. Escherichia spp., Klebsiella spp, Proteus spp., Shigella spp., Citrobacter spp. and Pseudomonas spp. were isolated. Sodium chloride content varied between 15.65 and 18.87% and no significant difference was observed (P > 0.05). Wa and pH showed significant differences (P < 0.05), with values between 0.71 and 0.75, and 5.54 and 5.93. TVB values varied between 15.1 and 62.1 mg N 100 g,1, showing significant differences (P < 0.05) as well. Worrying levels of histamine were found. Processing method A was found to be the most appropriate for the production of this kind of fish. [source] Kavut, a traditional Turkish cereal product: production method and some chemical and sensorial propertiesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2006Mehmet Murat Karao Summary Kavut is a cereal-based product made from wholemeal wheat and barley flour, milk or milk powder, fat and sugar. In this study, the best processing method and formulation were investigated by analysing different formulations and processing methods for the kavut. Four different flour combinations (100% wheat without barley, 75% wheat + 25% barley, 50% wheat + 50% barley, 25% wheat + 75% barley), two shortening (butter and margarine) and three different roasting periods (1, 1.5, 2 min) at 250 °C were used in the study. Significant changes were observed in the physical and chemical properties of the cereal by heat treatment in the kavut production. Increase of barley flour in the mixture decreased protein content, softness, altered L colour values, appearance, texture, mouth-feel, and general acceptance and increased ash content, +a and the absorbance value of kavut. While the longer roasting period resulted in reduced softness and colour (L-value) of kavut, roasting period did not significantly affect the general acceptance of kavut. Kavut made from only whole wheatflour was most preferred by the panellists. [source] Paste extrusion control and its influence on pore size properties of PTFE membranesADVANCES IN POLYMER TECHNOLOGY, Issue 3 2007Radium Huang Abstract Polytetrafluoroethylene (PTFE) is a remarkable membrane material. Owing to its high-melting point, PTFE fine powder cannot be processed using conventional melting processing methods. Instead, techniques such as paste extrusion, rolling, and sintering have to be employed. Each processing step has an important influence on the final pore size quality within the membrane. In this paper, a PID controller (proportional-integral-derivative controller) was used to improve the properties of PTFE paste during the extrusion process and the quality of the PTFE membrane. A range of lubricant content (18, 20, and 22 wt%) was used to monitor the pressure drop at different extrusion speeds (0.5, 1, and 2 mm/s) and reduction ratios (RR = 26.47, 47.06, 80.06). It was found that a higher lubricant content and a higher reduction ratio resulted in a lower pressure drop. It was also found that a higher stretching temperature tends to result in larger pore size and broader pore size distribution at the same stretching rate. At a monitored and controlled constant low-extrusion speed, the porosity of PTFE membrane was increased from 38% to 55% and the mean pore size was decreased from 0.22 to 0.15 ,m because of less migration and more uniform distribution of lubricant during extrusion. Properties and the associated property uniformity of the PTFE extrudate affect the subsequent membrane-forming process and the final pore size and size distribution significantly. © 2008 Wiley Periodicals, Inc. Adv Polym Techn 26:163,172, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20099 [source] Influence of processing conditions and physicochemical interactions on morphology and fracture behavior of a clay/thermoplastic/thermosetting ternary blendJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010M. Hernandez Abstract This study provides information on the mechanical behavior of epoxy-poly(methyl methacrylate) (PMMA)-clay ternary composites, which have been prepared using the phase separation phenomenon of PMMA and the introduction of organophilic-modified montmorillonites (MMTs), the continuous matrix being the epoxy network. Two dispersion processing methods are used: a melt processing without any solvent and an ultrasonic technique with solvent and a high-speed stirrer. TEM analysis shows that phase separation between PMMA and the epoxy network was obtained in the shape of spherical nodules in the presence of the clay in both process methods used. Nanoclay particles were finely dispersed inside thermosetting matrix predominantly delaminated when ultrasonic blending was used; whereas micrometer-sized aggregates were formed when melt blending was used. The mechanical behavior of the ternary nanocomposites was characterized using three-point bending test, dynamic mechanical analysis (DMA), and linear elastic fracture mechanics. The corresponding fracture surfaces were examined by scanning electron microscopy to identify the relevant fracture mechanisms involved. It was evidenced that the better dispersion does not give the highest toughness because ternary nanocomposites obtained by melt blending present the highest fracture parameters (KIc). Some remaining disordered clay tactoids seem necessary to promote some specific toughening mechanisms. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] KINETICS OF OSMOTIC DEHYDRATION IN ORANGE AND MANDARIN PEELSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2001M. CHÁFER ABSTRACT The nutritional and health properties of some citrus peel components such as pectin, flavonoids, carotenoids or limonene make interesting developing processing methods to obtain peel stable products, maintaining its quality attributes, increasing its sweetness and improving its sensory acceptability. In this sense, osmotic dehydration represents a useful alternative by using sugar solutions at mild temperature. Kinetics of osmotic treatments of orange and mandarin peels carried out at atmospheric pressure and by applying a vacuum pulse at the beginning of the process were analysed at 30, 40 and 50C, in 65 °Brix sucrose, 55 °Brix glucose and 60 °Brix rectified grape must. Vacuum pulse greatly affected mass transfer behavior of peels due to the greatly porous structure of albedo. So, PVOD treatments greatly accelerate the changes in the product composition in line with an increase in the peel sample thickness. In osmotic processes at atmospheric pressure, sample impregnation occurs coupled with osmotic process, but much longer treatments are required to achieve a reasonable concentration degree which assures sample stability. Low viscosity osmotic solutions seems recommendable in order to promote both diffusional and hydrodynamic transport, in vacuum pulsed pretreatments at mild temperatures. [source] OPTIMAL CONDITIONS FOR THE GROWTH AND POLYSACCHARIDE PRODUCTION BY HYPSIZIGUS MARMOREUS IN SUBMERGED CULTUREJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2009PING WANG ABSTRACTS In submerged cultivation, many nutrient variables and environmental conditions have great influence on the growth and polysaccharide production by Hypsizigus marmoreus. Plackett,Burman design was used to determine the important nutrient factors. A central composite experimental design and surface response methodology were employed to optimize the factor levels. Prediction models for dry cell weight (DCW), polysaccharide outside cells (EPS) and polysaccharide inside cells (IPS) under important nutrient conditions were developed by multiple regression analysis and verified. By solving the equations, the optimal nutrient conditions for highest EPS production (9.62 g/L) were obtained at 6.77 g cornstarch/L, 36.57 g glucose/L, 3.5 g MgSO4/L and 6.14 g bean cake powder/L, under which DCW and IPS were 16.2 g/L and 1.46 g/L, close to the highest value under their corresponding optimal conditions. Optimal environmental conditions were obtained at 10% inoculation dose, 45 mL medium in a 250 mL flask, pH 6.5, 25C and 200 rpm according to the results of single-factor experiment design. PRACTICAL APPLICATIONS Hypsizigus marmoreus polysaccharides have many functional properties, including antitumor, antifungal and antiproliferative activities, and free-radical scavenging. Liquid cultivation could produce a higher yield of polysaccharides and more flexible sequential processing methods of H. marmoreus, compared with traditional solid-state cultivation. However, the cell growth and production of polysaccharides would be influenced by many factors, including nutrient conditions and environmental conditions in the liquid cultivation of H. marmoreus. Keeping the conditions at optimal levels can maximize the yield of polysaccharides. The study not only found out the optimal nutrient conditions and environmental conditions for highest cell growth and yield of polysaccharides, but also developed prediction models for these parameters with important nutrient variables. Yield of polysaccharide inside of cells was also studied as well as polysaccharides outside of cells and cell growth. The results provide essential information for production of H. marmoreus polysaccharides by liquid culture. [source] EFFECTS OF COOKED TEMPERATURES AND ADDITION OF ANTIOXIDANTS ON FORMATION OF HETEROCYCLIC AROMATIC AMINES IN PORK FLOSSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2009GUOZHOU LIAO ABSTRACT Heterocyclic aromatic amines (HAAs) are an important class of food mutagens and carcinogens produced in meats cooked at high temperature. The formation of HAAs in pork floss during processing and the effect of vitamin C and vitamin E on HAAs formation in pork floss were studied. Pork floss was prepared by steaming of raw pork, followed by pressing, tearing, adding various additives, and then the cooked pork was subjected to stir frying. The various HAAs in pork floss were isolated by solid phase extraction and analyzed by high-performance liquid chromatography (HPLC). Results showed that the type and level of HAAs increased with increasing processing temperature. Up to seven HAAs, 9H-pyrido[4,3-b]indole (Norharman), 1-methyl-9H-pyrido[4,3-b]indole (Harman), 2-amino-1- methyl-6-phenylimidazo[4,5-f]pyridine (PhIP), 2-amino-dipyrido[1,2-a: 3,,2,-d]imidazole (Glu-P-2), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-9H-pyrido[2,3-b]indole (AaC) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAaC) were detected in pork floss when stir fried at 150C. Color development increased with cooking temperatures, and was correlated with HAAs formation. The addition of vitamin C at various levels was not effective toward HAAs inhibition. However, the incorporation of 0.1% vitamin E reduced Norharman, PhIP, AaC and MeAaC concentrations in the pork floss. PRACTICAL APPLICATION The formation of heterocyclic aromatic amines (HAAs) is one of the most unfavorable changes during the cooking of food. Since the connection between the consumption of dietary carcinogens and cancer risks in human has been established, interest in this matter has been growing. However, the processing methods and conditions of Chinese traditional food are different from Western, and to date, little is known about HAAs content in the traditional meat products of China. The information derived from this study serves as an essential base of knowledge from a public health standpoint, and contributes to a repository of HAAs information relevant to Chinese cooking; it also can provide clues to understanding the factors that affect HAAs formation and can indicate means of reducing or eliminating these compounds. [source] THE EFFECTS OF THERMAL AND NONTHERMAL PROCESSING METHODS ON APPLE CIDER QUALITY AND CONSUMER ACCEPTABILITYJOURNAL OF FOOD QUALITY, Issue 1 2005LYNN H. CHOI ABSTRACT Due to increased concern about the safety of fruit, vegetable and juice products, the FDA has mandated that these must undergo a 5-log reduction in pathogens. The development of various processing methods for juice products has caused the need to determine the effects of these methods on said products. The effect of thermal pasteurization, UV irradiation and ozone treatment on apple cider quality and consumer acceptability was studied over 21 days. Thermally pasteurized samples were different in color and less preferred in all areas of consumer acceptability. UV-irradiated samples were lower in soluble solids for the first 7 days and showed no significant difference in consumer acceptability. Ozone-treated cider had greater sedimentation, lower sucrose content and a decrease in soluble solids by day 21. UV irradiation allows for a more cost-effective method to produce safe apple cider with minimal quality and consumer acceptability differences. [source] Validation of LAB Color Mode as a Nondestructive Method to Differentiate Black Ballpoint Pen Inks,JOURNAL OF FORENSIC SCIENCES, Issue 4 2007Derek L. Hammond B.A. Abstract:, Nondestructive digital processing methods such as lab color mode (available in Adobe® Photoshop®) are emerging as alternative methods for forensic document examiners to use when attempting to differentiate writing instrument inks. Although these techniques appear to be viable, little data currently exists regarding the known or potential error rates associated with these techniques. Without adequate data, the validity and reliability of these techniques, including lab color, can not be established. In an attempt to begin to address these issues, 44 black ballpoint ink pens were obtained and used to create 990 pen-pair samples for analysis using established lab color mode techniques. No erroneous findings of "different" were reported following the examination of the known pen-pair combinations in which the same pen was used to create the samples (n = 44). Of the remaining 946 samples, 737 pen-pair samples were differentiated using the lab color mode method, while 209 samples were unable to be differentiated and were recorded as either being "similar" (n = 153) or "unsure" (n = 56). Comparison of the lab color mode results with the results obtained through additional testing using traditional infrared reflectance and infrared luminescence test methods showed that lab color differentiated 102 pen-pair samples (11%; 102/946) that were not differentiated using a VSC-4C. [source] Failure Modes with Point Loading of Three Commercially Available Denture TeethJOURNAL OF PROSTHODONTICS, Issue 6 2008Andrew R. Moffitt DDS Abstract Purpose: A common problem associated with implant-supported prostheses is the fracture of denture teeth. This study was designed to compare the fracture modes of three denture teeth by compressive load at a 30° off-axis angle. Material and Methods: Three denture teeth (Vident Duostat, Ivoclar Vivadent, and Dentsply Trubyte) processed to two denture base processing systems [injection-molded (IM) SR-Ivocap system and compression-molded (CM) denture base resin] were evaluated. Each specimen was processed to a metal framework. Ultimate failure strength of each system when point loaded at a 30° off-axis angle was recorded, along with a visual inspection of each specimen. Results: The average load fracture for each group was (in N): Vident CM 1106.97 ± 223.20, Vident IM 1168.18 ± 322.52, Dentsply CM 1098.08 ± 286.32, Dentsply IM 1023.80 ± 282.45, Ivoclar CM 1616.98 ± 204.87, and Ivoclar IM 1373.54 ± 282.58. There was a significant difference between the groups and the Ivoclar CM group. The Ivoclar CM group had the highest average load force, and the Dentsply IM group had the lowest average load force. On average, the teeth within the groups fractured at a higher compression force than the average maximum occlusal force in natural dentition. Dentsply and Vident denture teeth fractured more horizontally, and the Ivoclar denture teeth fractured more vertically within the groups. There was no significant difference among the groups between the IM and CM processing methods. Conclusions: In the present in vitro study, all specimens were able to withstand 30° off-axis loading with the exception of one specimen. With these results, this would indicate that these denture teeth are able to withstand normal occlusal forces. [source] Kinetic Studies of Mullite Synthesis from Alumina Nanoparticles and a Preceramic PolymerJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2008Flavio Griggio The crystallization kinetics of mullite formation in a diphasic precursor consisting of a silicone resin filled with commercial ,-alumina nanoparticles (15 nm mean particle size, specific surface area of 100 m2/g), heated in air from 1250° to 1350°C, was studied by X-ray diffraction. Transitional ,-alumina and amorphous silica from the pyrolysis of the preceramic polymer exhibited a remarkable reactivity, as demonstrated by a very low incubation time (from 500 s at 1250°C to 20 s at 1350°C), a high mullite yield (about 80 vol%, after 100 s at 1350°C), and a low activation energy for nucleation (677±60 kJ/mol). The activation energy values found were lower than those reported previously for other diphasic systems, including sol,gel precursors. Besides the high specific surface of nanosized ,-alumina particles, the low energy barrier could be attributed to the highly reactive silica deriving from the oxidation of Si,CH3 bonds in the silicone and to the homogeneous dispersion of the nanosized filler inside the preceramic polymer. Furthermore, the possibility of applying plastic shaping processing methods to the mixture of a preceramic polymer and nanosized filler makes this approach particularly valuable, in comparison, for instance, with sol,gel based alternatives. [source] Chemically Bonded Phosphate Ceramics: II, Warm-Temperature Process for Alumina CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2003Arun S. Wagh This is the second of three papers on a dissolution model that describes the formation of chemically bonded phosphate ceramics. In this paper, we discuss the kinetics of formation of aluminum phosphate ceramics between 100° and 150°C. Using basic thermodynamic formulations, we calculated the temperatures of maximum solubility of alumina and its hydrated phases and predicted the temperatures of formation of ceramics. Differential thermal and X-ray diffraction analyses on samples made in the laboratory confirm these temperatures. The resulting ceramics of alumina bonded with aluminum phosphate (berlinite) show a high compressive strength of 16 000 psi. We have concluded that rapid evaporation of excess water in the slurry generates porosity in the ceramics, and that better processing methods are needed. A consolidation model is presented that describes the microstructure of the ceramic. It predicts that a very small amount of alumina must be converted to form the bonding phase; hence, the product is mostly alumina with a thin coating of berlinite on the surface of alumina particles. [source] Processing of tomato: impact on in vitro bioaccessibility of lycopene and textural propertiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2010Cecilia A Svelander Abstract BACKGROUND: Human studies have demonstrated that processing of tomato can greatly increase lycopene bioavailability. However, the difference between processing methods is not widely investigated. In the current study different thermal treatments of tomato were evaluated with regard to their impact on in vitro bioaccessibility and retention of lycopene and ,-carotene as well as textural properties. Thermal treatments used were low (60 °C) and high (90 °C) temperature blanching followed by boiling. RESULTS: Lycopene was relatively stable during thermal treatment, whereas ,-carotene was significantly (P < 0.05) reduced by all heat treatments except for low temperature blanching. In vitro bioaccessibility of lycopene was significantly increased from 5.1 ± 0.2 to 9.2 ± 1.8 and 9.7 ± 0.6 mg kg,1 for low and high temperature blanching, respectively. An additional boiling step after blanching did not further improve lycopene bioaccessibility for any treatment, but significantly reduced the consistency of low temperature treated samples. CONCLUSION: Choice and order of processing treatments can have a large impact on both lycopene bioavailability and texture of tomato products. Further investigations are needed, but this study provides one of the first steps towards tomato products tailored to optimise nutritional benefits. Copyright © 2010 Society of Chemical Industry [source] Impact of sorghum processing on phytate, phenolic compounds and in vitro solubility of iron and zinc in thick porridgesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2007AP Polycarpe Kayodé Abstract This study focussed on the impact of process variables on levels of phytate and phenolic compounds, and in vitro solubility of iron (Fe) and zinc (Zn) in sorghum porridges, a major staple in semi-arid tropics. The aim was to identify practices that enhance the mineral availability in this type of staple food. We studied the example of the West African porridge ,dibou' for which the processing methods involve grain cleaning, milling, sieving and cooking. Regional variations occur in the process, particularly in the cleaning which may be done wet or dry; sieving may be omitted in certain locations. Cleaning reduced the phytate content of the grain by 24,39%, while milling, sieving and cooking had no significant effect on phytate. Phenolic compounds measured as levels of reactive hydroxyl groups, remained constant after cleaning, milling and sieving, but significantly decreased by 38,65% after cooking. The Fe solubility tended to increase after cleaning but was drastically reduced due to cooking, and so was the soluble Zn. Levels of total phenolic compounds highly correlated with the Fe and Zn solubility (r2 = 0.73 and 0.82, respectively). Phenolic reaction products formed during the cooking process are presumably related with the extensive browning phenomenon observed in the dibou porridge, and with the reduction observed in Fe and Zn solubility. Copyright © 2007 Society of Chemical Industry [source] Nutritional value of African yambean (Sphenostylis stenocarpa L): improvement by lactic acid fermentationJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2005Marshall A Azeke Abstract Tropical African yambean (Sphenostylis stenocarpa L) is an under-utilised hardy, protein-rich legume. Antinutrients and the excessively long cooking time (4,6 h), among other factors, limit the food use of African yambean seeds. To reduce these limitations, non-traditional, less energy-consuming processing methods are required. Seeds of different varieties were (i) examined for ingredients and (ii) fermented with Lactobacillus plantarum. Comparisons with traditionally cooked beans were made. Protein content and in vitro protein digestibility were increased slightly by fermentation or cooking. Reductions in trypsin and ,-amylase inhibitor activity and tannin ranged from significant to complete. The contents of potentially very toxic cyanogenic glycosides and flatulence-causing ,-galactosides were high in raw beans. Reduction by fermentation (by 85%) was clearly more effective than by traditional cooking (10,20%). The results demonstrate (i) that fermentation can substantially improve the nutritional quality and (ii) that the energy requirement to produce a basic consumable fermented food from African yambean is only 10% of that of traditional cooking. On these grounds, widespread application of lactic acid fermentation by individuals or small-scale industries would be advantageous in the context of small-household economy, environmental protection, health and long-term sustainable agriculture in Nigeria. Copyright © 2005 Society of Chemical Industry [source] Optimization of hot water extraction of roselle juice using response surface methodology: a comparative study with other extraction methodsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2003Peng-Kong Wong Abstract Roselle has regained the attention of many fruit juice manufacturers in Malaysia as a product that contains high ascorbic acid and anthocyanins. However, ascorbic acid and anthocyanin pigments can be easily destroyed during processing of fruit juice. Therefore, in the present study, the effects of different processing methods, namely hot water extraction (HWE), hot water blending, cold water blending and screw press, on the changes in anthocyanins and ascorbic acid contents of roselle juice were evaluated. The anthocyanins and ascorbic acid contents of roselle were determined using the pH differential method and high-performance liquid chromatography respectively. The physico-chemical characteristics and sensory properties of roselle juice were also evaluated. The results of the study indicate that the HWE method is the most effective extraction method, resulting in high anthocyanins and ascorbic acid contents of 43 g l,1 (as delphinidin-3-glucoside) and 2.34 g kg,1 respectively. The optimum juice extraction conditions were 3.5 h at 60 °C. Copyright © 2003 Society of Chemical Industry [source] Effects of cassava processing methods on antinutritional components and health status of children,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2002Omorogieva Ojo Abstract This study was conducted to evaluate cassava processing methods in Nigeria, its antinutritional components and the possible impact on the health status of children. The traditional method of cassava processing involved peeling of cassava tubers with a knife, manual grating, dewatering with logs of wood and/or stones, sieving with a cane-woven sieve and frying in a local metal fryer on a wood fire. In contrast, the modern method involved the use of knives for peeling, a mechanical grater, a hydraulic press for dewatering, iron sieves for sieving and an improved metal fryer for frying on a coal fire. The products of both methods included gari (accounting for 70% of Nigeria's total cassava consumption) and lafun. The intake of gari and other foods in 129 3,5-year-old children in Benin City, Nigeria was also assessed based on a food frequency questionnaire. The children were classified into normal and protein-deficient groups using lower/middle/upper-arm circumference and clinical features of malnutrition. Based on the number of households in villages around Benin City who were involved in cassava processing, 90% used the traditional processing method compared with 10% using the modern method, although the latter controlled the commercial production and sale of gari. There were significantly (P,<,0.05) higher intakes of protein and energy in normal compared with protein-deficient children, but the latter group obtained higher percentages of protein and energy from gari. In addition, the correlation between the amount of gari consumed and clinical scores of malnutrition was low (R2,<,0.2). This may be due to the children consuming gari from both methods and also from different sources. The average gari intake for these children was 320,g,day,1 and HCN levels may be as high as 10.24,mg,day,1. Some children who are exposed to these levels with poor nutritional status and lack of access to food varieties may develop sublethal effects in the short term. The higher protein intake by the normal children may also reduce the toxicity of HCN. We conclude that methods of processing cassava have profound effects on HCN retention and chemical composition of cassava products. In addition, the modern processing method is more efficient than the traditional method, with significantly reduced processing losses, labour input and levels of HCN. The HCN content in combination with the quantity and quality of protein in the diet has significant impact on the health status of children. Therefore, in susceptible children with poor nutritional status who consume inadequately processed cassava products with limited food choice, these may predispose them to the effects of HCN and thiocyanate. © 2002 Society of Chemical Industry [source] | ||||||||||||||||||||||||||||