Scott V.N.,U.S. Food and Drug Administration |
Powell M.,U.S. Department of Agriculture |
Cabrera J.,National Food Institute |
Carullo M.E.,National Service for Health and Quality |
And 2 more authors.
Food Control | Year: 2015
Milk powder to be consumed without further treatment to inactivate microorganisms was selected to illustrate the process for establishing and applying a microbiological criterion to assess the acceptability of a food lot. Example criteria (size of analytical unit, sampling plan and limits) were specified for mesophilic aerobic colony count and Enterobacteriaceae as indicators of the adequacy of Good Hygienic Practices and for Salmonella as a food safety criterion. Performance characteristics were determined for each criterion using four values for standard deviation of the microbial counts to illustrate how sampling plan performance depends on the within-lot standard deviation, which is uncertain for any given lot and varies among lots. Methods of analysis were specified. A description of how to interpret the results and examples of actions that could be taken by food business operators and competent authorities are provided. © 2014 Published by Elsevier Ltd. Source
Pastorczak M.,University of Lodz |
Pastorczak M.,University of Warsaw |
Dominguez-Espinosa G.,University of Lodz |
Dominguez-Espinosa G.,Technological Laboratory of Uruguay Latu |
And 6 more authors.
Colloid and Polymer Science | Year: 2014
Water interacting with a polymer reveals a number of properties very different to bulk water. These interactions lead to the redistribution of hydrogen bonds in water. It results in modification of thermodynamic properties of water and the molecular dynamics of water. That kind of water is particularly well observable at temperatures below the freezing point of water, when the bulk water crystallizes. In this work, we determine the amount of water bound to the polymer and of the so-called pre-melting water in poly(vinyl methyl ether) hydrogels with the use of Raman spectroscopy, dielectric spectroscopy, and calorimetry. This analysis allows us to compare various physical properties of the bulk and the pre-melting water. We also postulate the molecular mechanism responsible for the pre-melting of part of water in poly(vinyl methyl ether) hydrogels. We suggest that above -60 °C, the first segmental motions of the polymer chain are activated, which trigger the process of the pre-melting. © 2014 The Author(s). Source
Miguez D.M.,Technological Laboratory of Uruguay Latu |
Huertas R.,Technological Laboratory of Uruguay Latu |
Carrara M.V.,Technological Laboratory of Uruguay Latu |
Carnikian A.,Technological Laboratory of Uruguay Latu |
And 8 more authors.
Environmental Geochemistry and Health | Year: 2012
Bioassays of two sites along the Rio Negro in Uruguay indicate ecotoxicity, which could be attributable to trace concentrations of lead in river sediments. Monthly samples at two sites at Baygorria and Bonete locations were analyzed for both particle size and lead. Lead was determined by atomic spectrometry in river water and sediment and particle size by sieving and sedimentation. Data showed that Baygorria′s sediments have greater percentage of clay than Bonete′s (20.4 and 5.8%, respectively). Lead was measurable in Baygorria′s sediments, meanwhile in Bonete′s, it was always below the detection limit. In water samples, lead was below detection limit at both sites. Bioassays using sub-lethal growth and survival test with Hyalella curvispina amphipod, screening with bioluminescent bacteria Photobacterium leiognathi, and acute toxicity bioassay with Pimephales promelas fish indicated toxicity at Baygorria, with much less effect at Bonete. Even though no lethal effects could be demonstrated, higher sub-lethal toxicity was found in samples from Baygorria site, showing a possible concentration of the contaminant in the clay fraction. © 2011 Springer Science+Business Media B.V. Source