Noteworthy progress in the area of food packaging has recently introduced in order to inhibit or prevent microbial growth as well as to keep the products from further microbial deterioration. Among the food packaging techniques, active packaging, particularity antimicrobial active packaging, has attracted much attention, considering the diverse materials used, the methods of application in the variety of food products to be protected. Direct and indirect techniques can be utilized to apply antimicrobial compounds into food packaging materials. The increasing importance of the application of antimicrobial packaging has led to in a better knowledge of materials, and the factors affecting the effectiveness of antimicrobial systems. This article is a review of the antimicrobial agents, the materials used for delivering them, antimicrobial migrating and non-migrating systems and the effects of antimicrobial agents on packaging properties. In general, the use of antimicrobial active packaging extends the stability of food products during storage and distribution. However, many challenges of the new approaches of antimicrobial active packaging still remain including the controlled release of antimicrobial agents, and the development of packaging materials (mainly the bio-based materials) with adequate barrier properties, transparency, tensile strength and other required characteristics.

The aims were: (1) to follow the freshness decay of minced beef stored in high-oxygen modified atmosphere packaging at different temperatures (4.3, 8.1 and 15.5 degrees C) by applying traditional methods (microbiological counts, color evaluation, thiobarbituric acid assay TBA, headspace gas composition) and e-nose; (2) to model the decay kinetics to obtain information about the maximum shelf life as function of storage conditions. The minced beef, packaged in modified atmosphere was supplied by a manufacturer at the beginning of its commercial life. The study demonstrated the ability of the traditional methods to describe the kinetics of freshness decay. The modeling of the experimental data and the comparison with microbiological or chemical thresholds allowed the setting, for each index, of a stability time above which the meat was no longer acceptable. The quality decay of meat was also evaluated by the headspace fingerprint of the same set of samples by means of a commercial e-nose. A clear discrimination between "fresh" and "old" samples was obtained using PCA and CA, determining at each temperature a specific range of stability time. The mean value of the stability times calculated for each index was 9 days at 4.3 degrees C (recommended storage temperature), 3-4 days at 8.1 degrees C (usual temperature in household refrigerators) and 2 days at 15.5 degrees C (abuse temperature). Resolution of the stability times allowed calculation of mean Q(10) values, i.e. the increase in rate for a 10 degrees C increase in temperature. The results show that the Q(10) values from the traditional methods (3.6-4.0 range) overlapped with those estimated with e-nose and color indexes (3.4 and 3.9, respectively).

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The aim of this work was to evaluate the effects of wheat germ -stabilized by toasting or by sourdough fermentation -on dough and bread properties. Doughs were produced by adding increasing amounts of each type of stabilized germ, starting with the current recommended level of 3g/100g up to 20g/100g. Sourdough fermentation ensured the presence of lactic acid bacteria (LAB) in amounts comparable to those found in conventional sourdough. The acidification induced by LAB inactivates lipase and lipoxygenase, as does the toasting process. These results decreased the phenomena of rancidity, as demonstrated by the low development of hexanal during storage. Fermentation significantly decreased the content of glutathione, responsible for the deterioration of the rheological characteristics and workability of dough containing high levels of germ. Dough enriched with fermented germ exhibited high stability during mixing and development. Positive effects associated with the use in bread-making of germ stabilized by fermentation have been detected both in fresh bread (high specific volume) and in bread samples stored up to 4 days in controlled conditions of humidity and temperature. Finally, the sensory consumers' test confirmed that the addition of fermented germ did not diminish the liking of the sample.