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Time-temperature indicators (TTIs) are used to check the safety of the fresh foods with reduced oxygen packaging (ROP). Already, the behavior of TTIs with zero-order kinetic was described based on Skinner-Larkin model. For TTI expiration before toxin formation, the Arrhenius curve of TTI (in the coordinates system of lnk versus 1/T) should be located above the zero-order Skinner-Larkin-Arrhenius curve (SLA0) for all possible temperatures. However, SLA0 may incorrectly describe TTIs behaviors since they often provide first-order kinetic (similar to most natural processes). Developing a new model to describe the behavior of all types of TTIs (with zero or first-order kinetic) for fresh seafoods with ROP is the main goal of this research. In this paper, the first-order Skinner-Larkin-Arrhenius (SLA1) model is proposed as a pencil of curves to extend SLA0 for the TTIs with first-order kinetic. Furthermore, because of including the SLA0 curve, the SLA1 model can be equivalently used for both zero-order and first-order TTIs. Simulation results demonstrated that SLA0 could not correctly predict the behavior of first-order TTIs. By using the proposed model, we can successfully predict the behavior of both zero-order and first-order TTIs for fresh seafoods with ROP.