title: Thermal inactivation kinetic modeling of human norovirus surrogates in blue mussel (Mytilus edulis) homogenate.
abstract: Control of seafood-associated norovirus outbreaks has become an important priority for public health authorities. Due to the absence of human norovirus infectivity assays, cultivable surrogates such as feline calicivirus (FCV-F9) and murine norovirus (MNV-1) have been used to begin to understand their thermal inactivation behavior. In this study, the effect of thermal treatment on inactivation of human norovirus surrogates in blue mussels was investigated at 50, 56, 60, 65, and 72 °C for various times (0-6 min). The results obtained were analyzed using the Weibull and first-order models. The Theil error splitting method was used for model comparison. This method splits the error in the predicted data into fixed and random error. This method was applied to select satisfactory models for determination of thermal inactivation of norovirus surrogates and kinetic modeling. The D-values calculated from the first-order model (50-72 °C) were in the range of 0.07 to 5.20 min for FCV-F9 and 0.18 to 20.19 min for MNV-1. Using the Weibull model, the t(D=1) for FCV-F9 and MNV-1 to destroy 1 log (D=1) at the same temperatures were in the range of 0.08 to 4.03 min and 0.15 to 19.80 min, respectively. The z-values determined for MNV-1 were 9.91±0.71 °C (R²=0.95) using the Weibull model and 11.62±0.59 °C (R²=0.93) for the first-order model. For FCV-F9 the z-values were 12.38±0.68 °C (R²=0.94) and 11.39±0.41 °C (R²=0.97) for the Weibull and first-order models, respectively. The Theil method revealed that the Weibull model was satisfactory to represent thermal inactivation data of norovirus surrogates and that the model chosen for calculation of thermal inactivation parameters is important. Knowledge of the thermal inactivation kinetics of norovirus surrogates will allow development of processes that produce safer shellfish products and improve consumer safety.
authors.affiliation: Department of Food Science and Technology, The University of Tennessee, 2600 River Drive, Knoxville, TN 37996-4591, USA.
authors.forename: Hayriye
authors.initials: H
authors.lastname: Bozkurt
authors.affiliation: Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstraße 25, 70599 Stuttgart, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Leiser
authors.affiliation: Department of Food Science and Technology, The University of Tennessee, 2600 River Drive, Knoxville, TN 37996-4591, USA.
authors.forename: P Michael
authors.initials: PM
authors.lastname: Davidson
authors.affiliation: Department of Food Science and Technology, The University of Tennessee, 2600 River Drive, Knoxville, TN 37996-4591, USA. Electronic address: ddsouza@utk.edu.
authors.forename: Doris H
authors.initials: DH
authors.lastname: D'Souza
mesh_terms: D000818:Animals; D017927:Calicivirus, Feline / Q000502:physiology*; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D007700:Kinetics; D008954:Models, Biological; D049880:Mytilus edulis / Q000821:virology*; D029322:Norovirus / Q000502:physiology*; D013696:Temperature; D038301:Virus Inactivation
keywords: D- and z-values; Feline calicivirus; First-order and Weibull models; Murine norovirus; Mytilus edulis; Theil method