The potato (Solanum tuberosum) is one of the main sources of natural starch. In recent decades, the valorisation of potato protein that results as a by-product in the starch industry has been gaining interest as well. As potato supply is seasonal and the protein content of potatoes during long-term storage is temperature-dependent, optimal storage of potatoes is of great importance. This paper explores a model describing potato protein content during a full storage season for the Miss Malina and Agria cultivars. The model combines Michaelis-Menten protein kinetics with the Arrhenius equation. Laboratory analyses were performed to monitor the protein components in both potato cultivars and to use for estimation of the kinetic parameters. The results indicate that the two cultivars have different synthesis and degradation kinetics.