(640f) Flame Spray Synthesis Of Nanoparticles For Food Applications: Synthesis, Characterization, Potential Hazards, Cost And Scalability

Due to their small size nanoparticles are considered to be promising materials in a broad area of applications within the food industry. Potential use includes food packaging (e.g. anti-microbial or antifungal films), food processing (e.g. gelation, viscosifying agent) or the direct use of nano-scale materials as food additives. However, it is well known that compared to their bulk counterparts, nanoparticles have new chemical and physical properties. It has become clear that these new properties may also influence the interaction of nanoparticles with living systems and could result in unexpected toxicological responses. Recent advances in the large-scale production of nanoparticles by flame spray synthesis not only made a very wide variety of (mixed) oxides accessible to this process, but now even salts [1] and metals [2] can be prepared at large-scale by the flame based process. The availability of these new processes has yielded in a stronger market pull, making a proper hazard analysis and process control necessary for the scale-up process. In this contribution we investigated the categorical suitability of specific nanoparticles for possible applications within the food sector. Besides necessary particle characterization methods, possible process control mechanisms of the flame spray process adapted to the requirements of the food industry and suitable toxicity tests required for the application as food additives are proposed. Thereby, a hazard analysis and critical control point (HACCP) identification is presented. The acceptability of flame derived nanoparticles for food applications is discussed from a consumer's and a producer's viewpoint. Required safety protocols for researchers or factory workers operating with nanoparticulate material are treated. Finally, cost [3] and scalability [4] of the flame spray synthesis are addressed.

References:

[1] S. Loher, W.J. Stark, M. Maciejewski, A. Baiker, S.E. Pratsinis, D. Reichardt, F. Maspero, D. Günther, Fluoro-apatite and calcium phosphate nanoparticles by flame synthesis, Chem. Mater. 17 (1), 36-42 (2005).

[2] R. N. Grass, W.J. Stark, Gas phase synthesis of fcc-cobalt nanoparticles, J. Mater. Chem., 16, 1825-30 (2006).

[3] N. Osterwalder, C. Capello, K. Hungerbühler and W. J. Stark, Energy Consumption During Nanoparticle Production: How Economic is Dry Synthesis?, J. Nanopart. Res., 8 (1), 1-9 (2006).

[4] W. J. Stark, H. K. Kammler, R. Strobel, A. Baiker, S. E. Pratsinis, Flame-made titania/silica epoxidation catalysts: Toward large-scale production, Ind. Eng. Chem. Res., 41, 4921-4927 (2002).