Detaild Report on the Second European Inter-Laboratory Comparison Study on the Determination of Acrylamide in Food. Acrylamide in Crispbread Samples.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

Challenges in the Up-scaling of Resorcinol-Formaldehyde Aerogel Micro-beads Production by Jet-Cutting Method

Carbon aerogels (CAs) are excellent materials with high surface area and unique micro-structures consisting nano-particles and nano-pores. CAs find potential applications in catalysis, chromatography, energy, adsorbents, desalination, etc. In recent times, research-ers focused on the development of CAs in the form of micro-spheres and/or micro-beads due to the reduction in process time and equipment costs for various applications. Car-bon micro-beads are produced from coal or petroleum pitch by carbonizing at 350-500 °C to achieve mesophase spheres in pitch. The carbonization is quenched before an exten-sive growth and aggregation of the spheres and separated as solids from soluble pitch by extraction with a solvent. Carbon aerogel micro-beads of 1 m to 3 mm are also fabricat-ed by using an inverse emulsion gelation of resorcinol-formaldehyde (RF) solution at ele-vated temperatures followed by freeze drying or super-critical drying and subsequent carbonization. The freeze drying or super-critical drying techniques consume large amount of solvents, energy and time for the large scale production. Herein, we report the development of RF aerogel micro-beads through dropping method. The shaping of RF sol solution into a micro-beads is quite challenging because of its low apparent viscosity ( 0.5 Pa.s) and faster sol-gel transition. Hence, we aimed to improve the viscosity of the RF sol solution using a sustainable polysaccharide based thickener to achieve suitable viscosity (1 - 10 Pa.s) in-order to shape them into a micro-beads. The pre-gelled RF sol solution with various concentrations of thickener is dropped into an acid bath to form micro-beads followed by curing, washing and ambient pressure drying and carbonization. The ambient pressure drying of the micro-beads is one of the greatest advantages of the process in-terms of low-cost. The overview of the RF and Carbon aerogel micro-beads production at the laboratory and large scale is depicted in Fig. 1. However, large scale production of RF aerogel micro-beads by Jet-Cutting method poses several challenges viz., handling of enormous amounts of RF sol and acid bath, process parameter optimization, waste disposal, etc. Hence, we adopted low to high viscous alginate solution (0.5 - 3wt.%) with a viscosity ranging from 0.08 to 10 Pa.s, as a model system to optimize the Jet-Cutting parameters. The diameter of the beads (dbead) can be described in eq. 1. d_bead= 3√(3/2 D^(2 ) (u_fluid/(n.Z)-d_wire ) ) -------(1) Where, D - diameter of the nozzle, ufluid - fluid velocity, n - number of cutting wires, Z - number of cutting tool rotation, dwire - diameter of the wire. The operation of Jet-Cutter for the production of micro-beads with low-viscous fluid is no means of complicated. However, the fluid velocity, diameter of the nozzle and number of cutting tool rotation need to be understood. In the next step, large scale production of the RF micro-beads using Jet-Cutting method will be optimized and demonstrated

Impact of Engineered Nanomaterials on Health: Considerations for Benefit-Risk Assessment

Nanotechnology encompasses the design, characterisation, production and application of materials and systems by controlling shape and size at the nanoscale (nanometres). Nanomaterials may differ from other materials because of their relatively large specific surface area, such that surface properties become particularly important. There has been rapid growth in investment in nanotechnology by both the public and private sectors worldwide. In the EU, nanotechnology is expected to become an important strategic contributor to achieving economic gain and societal and individual benefits. At the same time there is continuing scientific uncertainty and controversy about the safety of nanomaterials. It is important to ensure that timely policy development takes this into consideration. Uncertainty about safety may lead to polarised public debate and to business unwillingness to invest further. A clear regulatory framework to address potential health and environmental impacts, within the wider context of evaluating and communicating the benefit-risk balance, must be a core part of Europe's integrated efforts for nanotechnology innovation. While a number of studies have been carried out on the effect of environmental nanoparticles, e.g. from combustion processes, on human health, there is yet no generally acceptable paradigm for safety assessment of nanomaterials in consumer and other products. Therefore, a working group was established to consider issues for the possible impact of nanomaterials on human health focussing specifically on engineered nanomaterials. This represents the first joint initiative between EASAC and the Joint Research Centre of the European Commission. The working group was given the remit to describe the state of the art of benefits and potential risks, current methods for safety assessment, and to evaluate their relevance, identify knowledge gaps in studying the safety of current nanomaterials, and recommend on priorities for nanomaterial research and the regulatory framework. This report focuses on key principles and issues, cross-referencing other sources for detailed information, rather than attempting a comprehensive account of the science. The focus is on human health although environmental effects are also discussed when directly relevant to healt

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Synthesis and Characterization of Resorcinol-Formaldehyde (RF) and Carbon Aerogel Microbeads by Dropping Method

Resorcinol formaldehyde (RF) aerogel microbeads have been shown to improve the quality of metal castings when mixed with the casting sand. Reports for the production of RF aerogel microbeads mostly involve emulsion gelation methods, which have the disadvantage of a complicated upscaling of the synthesis. Hence, the aim of this work is to investigate the synthesis conditions of RF aerogel microbeads with a dropping method. Xanthan gum (XG) was added to a RF sol to increase its viscosity. A XG containing base-catalyzed pre-gelled sol was then dropped into hydrochloric acid to induce rapid gelation of the droplets. After ambient drying the gels were fully characterized concerning their size, bulk and skeletal densities, porosities, surface area, pore size distribution, IR spectra and microstructure. The here described reaction parameters can in future be transferred to a mechanical JetCutter for easy upscaling of the process

Acrylamide Analysis: Evaluation of the Results from an Interlaboratory Comparison Study on Crispbread samples

The European Commission's Directorate general joint research centre organized so far several proficiency tests on the determination of acrylamide (AA) in food. This paper presents the results and outcome of a proficiency tests, which focused on the determination of AA in crispbread samples. One of the goals was the identification of the influence of different parameters such as analyte extraction or instrument calibration on the analytical results. Therefore, a set of samples containing three different crispbread samples, as well as extracts of one crispbread sample and AA standard slution, where shipped to each participant. A number of 42 european laboratories reported analytical results that were evaluated by applying internationally accepted protocols and procedures. The study rendered that for each sample, the results of 4 to 8 laboratories were outside the range formed by the target value plus/minus the twofold of the target standard deviation, thus they did not perform satisfactorily. In transferring this knowledge to the data of monitoring databases of AA in food, care must be taken that data are quality controlled as it is likely that some of them may be biased.JRC.D.8-Food safety and qualit

Acrylamide in Food: a Survey of Two Years of Research Activities

The report in April 2002 of high levels of the chemical compound acrylamide in starch-rich, processed food has caused widespread public attention due to its classification as probably carcinogenic to humans. Since this issue concerning the formation of acrylamide during food processing was totally new, a significant amount of knowledge had to be acquired. The central question was, and is, to what extent the acrylamide contents in food affect human health.JRC.D.8-Food safety and qualit

European Union Database on Acrylamide Levels in Food - Update and Critical Review on Data Collection

The European Commission's Directorate General Joint Research Centre has been collecting data produced in EU Member States on the acrylamide (AA) content of food since 2003. More than 9000 individual data have been received from official food control laboratories directly or via their competent authorities, and from the food industry. Before entering the database, the data were assessed for their reliability. This paper presents an upate of the database as well as results of the evaluation of data for selected food commodities in order to establish a trend concerning the contents of AA in food. Experiences gained with the data collection and data assessment are described and recommendations for future data collection initiatives are given.JRC.D.8-Food safety and qualit

European Union Database of Acrylamide Levels in Food: Update and Critical Review of Data Collection

The European Commission's Directorate General Joint Research Centre has been collecting data produced by European Union Member States on the acrylamide content of food since 2003. More than 9000 individual data points have been received from official food control laboratories directly or via their Competent Authorities, and from the food industry. Before being entered into the database, the data were assessed for their reliability. This paper presents an update of the database as well as results of the evaluation of data froselected food commodities in order to establish a trend concerning the content of acrylamide in food. Experience gained with the data collection an data assessment are described and recommendations for future data collection initiatives given.JRC.I-Institute for Health and Consumer Protection (Ispra