A study on the physicochemical parameters for Penicillium expansum growth and patulin production: effect of temperature, pH, and water activity

Joanna Tannous (1, 2) , Ali Atoui (3, 4) , André El Khoury (2) , Ziad Francis (2) , Isabelle P. Oswald (5) , Olivier Puel (5) , Roger Lteif (2)

1 ToxAlim - ToxAlim
2 Saint Joseph University
3 LU / ULB - الجامعة اللبنانية [بيروت] = Lebanese University [Beirut] = Université libanaise [Beyrouth]
4 Laboratory of Microorganisms and Food Irradiation
5 ToxAlim-BioToMyc - Biosynthèse & Toxicité des Mycotoxines

Penicillium expansum is among the most ubiquitous fungi disseminated worldwide, that could threaten the fruit sector by secreting patulin, a toxic secondary metabolite. Nevertheless, we lack sufficient data regarding the growth and the toxigenesis conditions of this species. This work enables a clear differentiation between the favorable conditions to the P. expansum growth and those promising for patulin production. A mathematical model allowing the estimation of the P. expansum growth rate according to temperature, a W, and pH, was also developed. An optimal growth rate of 0.92 cm/day was predicted at 24 degrees C with pH level of 5.1 and high a W level of 0.99. The model's predictive capability was tested successfully on artificial contaminated apples. This model could be exploited by apple growers and the industrialists of fruit juices in order to predict the development of P. expansum during storage and apple processing.

Mots clés: patulin production; Penicillium expansum; pH; predictive mycology; temperature; water activity; Growth rate

Domaines: Sciences du Vivant [q-bio]

Joanna Tannous, Ali Atoui, André El Khoury, Ziad Francis, Isabelle P. Oswald, et al.. A study on the physicochemical parameters for Penicillium expansum growth and patulin production: effect of temperature, pH, and water activity. Critical Reviews in Food Science and Nutrition, 2016, 4 (4), pp.611-622. ⟨10.1002/fsn3.324⟩. ⟨hal-02638867⟩