Technological properties of durum wheat semolina treated by heating and UV irradiation for reduction of mycotoxin content

Abstract: Physical methods, such as heating and irradiation with ultraviolet light (UVC), are among the strategies that may be used to reduce mycotoxin content in foodstuffs. This research studied the technological effects of heating at 100, 150, and 200 °C and UVC irradiation at 254 nm for 15, 30, 60, and 120 min applied on semolina to decrease the amount of mycotoxins. The impact of the most efficient treatments (150 °C for 30 min and UVC irradiation for 120 min) was evaluated both on semolina and dough technological properties, such as color, hydration, and gluten indices, farinograph and calorimetric parameters, and microstructure. Thermal treatment significantly increased hydration of semolina and swelling power; farinograph analyses revealed a marked increase in water absorption and dough development time and a reduction of dough stability and degree of softening and elasticity compared to the control. Calorimetric analyses showed a significant reduction in both temperature peaks and enthalpy of starch gelatinization and a decrease in enthalpy for melting of lipids with starch. Scanning electron micrograph images representing the dough microstructure confirmed the occurrence of these changes; UVC-treated samples showed less pronounced changes compared to the control. Practical applications: This work reports some strategies that could be integrated in semolina-based products chains, with the aim of reducing mycotoxin contamination. Thermal treatment and UVC irradiation are known to be cost-effective techniques, combining a high thermal efficiency with the simplicity of application. Understanding the technological changes resulting from these treatments could be useful to food companies for the realization of safer semolina-based products with different structural properties. This is the first study aiming to investigate the technological impacts of physical processing methods for reducing mycotoxin contamination.