Page 24

eFOODLab_International_03_2014

Colour Weight g Piperine g/L Essential oils L a b ΔE mL/100g untreated 30.74 1.78 0.93 - 100 ± 0.5 0.47 ± 8.1*10-5 2.9 ± 0.2 15 min direct 27.53 1.59 0.99 94.4 ± 0.7 0.46 ± 1.7*10-3 2.7 ± 0.2 plasma used to run the plasma jet. Given that the penetration depth of the both used plasmas is only a few μm, the aroma compounds of the pepper seeds were not affected. Is a plasma application accepted for the preservation decontamination of food? Products or product groups treated with plasma must be subjected to a case-by-case assessment. The plasma process must be described with respect to its technical parameters. This not only applies to the process itself (working gas, degree of ionization, treatment geometry, exposure time, temperature, pH value, system layout, etc.). In addition, a profile as comprehensive as possible of the plasma-induced physical/chemical/ biochemical/microbiological changes in the food is required (Schlüter et al., 2013). No investigations have been conducted so far on whether toxic compounds are formed as a result of plasma treatment. At present, the available information regarding the consequences of plasma treatment on various foods is insufficient for a safety assessment of the process. The impact on microbiological safety must also be taken into account in order to achieve an adequate health evaluation. In the case that plasma treatment leads to significant changes and affects the nutritional value, constituent composition and/or content of undesirable substances in the food, the treated products must be considered within the scope of the Novel Food Regulation. Conclusions The low temperature atmospheric plasma treatment offers various opportunities in food processing, like a controlled modification of surface properties or a gentle surface decontamination. This novel technology is suitable to increase the microbial safety of fresh produce or dry products. Especially the indirect plasma treatment of whole black pepper opens new perspectives for lowering the microbial count on seed surfaces. However, for a health and/or risk assessment, data for plasma-product-interactions are still too scarce. This also applies especially on potential compositional changes in the food, especially with regard to potentially harmful components. Anyhow, the obtained data about the antimicrobial properties of plasma processed air towards spores and the TPC are very promising. References 1 Boudam, M.K., Moisan, M., Saoudi, B., Popovici, C., Gherardi, N., Massines, F., 2006. Bacterial spore inactivation by atmosphericpressure plasmas in the presence or absence of UV photons as obtained with the same gas mixture. JOURNAL OF PHYSICS D: APPLIED PHYSICS 39, 3494-3507. 24 3/14 eFOOD-Lab international 2 Brandenburg, R., Lange, H., von Woedtke, T., Stieber, M., Kindel, E., Ehlbeck, J., Weltmann, K.D., 2009. Antimicrobial Effects of UV and VUV Radiation of Nonthermal Plasma Jets. Ieee Transactions on Plasma Science 37, 877-883. 3 Ehlbeck, J., Schnabel, U., Polak, M., Winter, J., von Woedtke, T., Brandenburg, R., von dem Hagen, T., Weltmann, K.D., 2011. Low temperature atmospheric pressure plasma sources for microbial decontamination. Journal of Physics D-Applied Physics 44. 4 Froehling, A., Durek, J., Schnabel, U., Ehlbeck, J., Bolling, J., Schlueter, O., 2012. Indirect plasma treatment of fresh pork: Decontamination efficiency and effects on quality attributes. Innovative Food Science and Emerging Technologies 16, 381-390. 5 Gianotti, A., Iucci, L., Guerzoni, M.E., Lanciotti, R., 2009. Effect of acidic conditions on fatty acid composition and membrane fluidity of Escherichia coli strains isolated from crescenza cheese. Annals of Microbiology 59, 603-610. 6 Knorr, D., Froehling, A., Jaeger, H., Reineke, K., Schlueter, O., Schoessler, K., 2011. Emerging technologies in food processing. Annual Review of Food Science and Technology 2, 203-235. 7 Laroussi, M., 2005. Low temperature plasma-based sterilization: Overview and state-of-the-art. Plasma Processes and Polymers 2, 391-400. 8 Mastwijk, H.C., Nierop Groot, M.N., 2010. Use of cold plasma in food processing, in: Heldman, D.R., Bridges, A., Hoover, D., Wheeler, M.B. (Eds.), Use of cold plasma in food processing. Taylor & Francis, New York. 9 Roth, J.R., 1995. Industrial Plasma Engineering, Volume 1: Principles. Inst. Phys. Publ, Bristol and Philadelphia. 10 Rutscher, A., 2008. Characteristics of low-temperature plasmas under nonthermal conditions: a short summary, in: Hippler, R., Kersten, H., Schmidt, M., Schoenbach, K.H. (Eds.), Low Temperature Plasmas: Fundamentals, Technologies, and Techniques. Wiley-VCH Verlag GmbH & Co KGaA, Weinheim. 11 Schlüter, O., Ehlbeck, J., Hertel, C., Habermeyer, M., Roth, A., Engel, K.H., Holzhauser, T., Knorr, D., Eisenbrand, G., 2013. Opinion on the use of plasma processes for treatment of foods*. Molecular Nutrition & Food Research 57, 920-927. 12 Setlow, P., 2007. I will survive: DNA protection in bacterial spores. Trends in Microbiology 15, 172-180. 13 Weltmann, K.D., Brandenburg, R., von Woedtke, T., Ehlbeck, J., Foest, R., Stieber, M., Kindel, E., 2008. Antimicrobial treatment of heat sensitive products by miniaturized atmospheric pressure plasma jets (APPJs). Journal of Physics D-Applied Physics 41. 14 Yuk, H.G., Marshall, D.L., 2004. Adaptation of Escherichia coli O157 : H7 to pH alters membrane lipid composition, verotoxin secretion, and resistance to simulated gastric fluid acid. Applied and Environmental Microbiology 70, 3500-3505. 60 min indirect plasma 29.15 2.27 1.11 1.67 99.7 ± 0.5 0.45 ± 1.4*10-3 2.8 ± 0.2 thermal treatment 31.68 1.95 0.84 0.94 0.46 ± 1.9*10-3 2.9 ± 0.2 Table 2. Relevant product quality parameters for whole black pepper untreated, thermal treated and after plasma exposure Innovative Processi ng Tech nolo gies


eFOODLab_International_03_2014
To see the actual publication please follow the link above