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Several quality parameters affecting Alaska pollack, Theragra chalcogramma, were measured and modeled kinetically under storage at different temperatures: the K-value, trimethylamine (TMA), volatile basic nitrogen (VBN), Torry meter, pH, acid value (AV), total viable cell count (TVC), and colony forming units (CFU) of Pseudomonas spp. The off-flavor development time (ODT) was also measured using the R-index sensory test and modeled kinetically. Among the quality parameters, the CFU of Pseudomonas spp. was an indicator of the ODT according to a similarity in the Arrhenius temperature dependence, which was derived as a criterion mathematically. The temperature dependence was represented by the Arrhenius's activation energy (E a ). On comparing the E a of the quality factors and the ODT, the similarity in the temperature dependence was found to be high in the order Pseudomonas spp., pH, VBN, TVC, K-value, TMA, AV, and Torry meter. Therefore, Pseudomonas spp. was identified as the primary indicator of ODT.

Dynamic modeling was used to predict the Pseudomonas spp. concentration in Alaska pollack under dynamic temperature conditions in a programmable incubator using Euler's method. The model evaluation showed good agreement between the predicted and measured concentrations of Pseudomonas spp. In the simulation, three kinds of distribution path were assumed: consumers buying from a distribution center (A), manufacturer (B), or direct market (C). Each of these distribution paths consists of six phases: shipping, warehousing/ shipment, warehousing/storing, processing, market exhibition, and sale/consumption. Sensitivity analysis of each phase was also implemented. The Pseudomonas concentrations and sensitivities (S k ) at the terminal phases of the three paths were estimated to be (A) 11.174 log CFU/g and 10.550 log S k , (B) 10.948 log CFU/g and 10.738 log S k , and (C) 8.758 log CFU/g and 9.602 log S k , respectively. The sensitivities indicated that path A has the highest risk of failure in managing the relevant phases.