title: Kinetics of peroxidase inactivation in carrot juice treated with pulsed electric fields.
abstract: Peroxidase activity accounts for quality losses in many plant-based foods. The paper provides insight into the inactivation kinetics of peroxidase (POD) in carrot juice treated with pulsed electric fields (PEF). Juice samples were subjected to electric field intensities of 20 to 35 kV/cm for 300 to 2000 μs. Up to 93% of the initial activity was inactivated after treating at 35 kV/cm for 1500 μs. POD activity inactivation correlated well with the increase in energy density input. A first-order fractional conversion model best fitted the experimental results. Other kinetic approaches such as the Fermi's model can be used to estimate residual POD activity values in treated juices as a function of electric field strength.
  
  
  CONCLUSIONS
  Pulsed electric fields (PEF) are a processing technology that can be used for the pasteurization of liquid food products. Peroxidase activity inhibition is required in carrot juices to prevent undesirable quality losses, such as discoloration, flavor changes, and loss of nutrients. The most significant processing parameters ruling POD inactivation in PEF-treated carrot juice are identified and mathematical modeling of experimental data is conducted.
authors: Dept. of Food Technology, DTA/UFV, Univ. Federal de Viçosa, Campus universitário, Cep., 36571-000, Viçosa, MG, Brazil.
authors: Luciano José
authors: LJ
authors: Quintão-Teixeira
authors: Robert
authors: R
authors: Soliva-Fortuny
authors: Afonso
authors: A
authors: Mota Ramos
authors: Olga
authors: O
authors: Martín-Belloso
mesh_terms: D001628:Beverages / Q000032:analysis*; D018552:Daucus carota / Q000201:enzymology*; D004560:Electricity; D005511:Food Handling / Q000379:methods*; D007700:Kinetics; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D061352:Pasteurization; D009195:Peroxidase / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D009195:Peroxidase