*3.2. Extrusion and Fermentation*

Extrusion is a type of high-temperature treatment, and as discussed previously, it can decrease the number of mycotoxins in cereals [68]. Contradictory results were indicated by Zokaityte et al. They found that extrusion may affect the mycotoxin levels differently by increasing, decreasing, or not changing their concentrations in the samples. The combination of extrusion at different temperatures (115 and 130 ◦C), over different screw speeds (16, 20, and 25 rpm), with fermentation for 24 h at 30 ◦C by using 2 strains of LAB (*Lactobacillus casei* and *Lactobacillus paracasei*) and their effects have also been studied. This combination increased the amount of lactic acid and decreased bacterial contamination as a result of pH reduction. The effect of extrusion on different mycotoxins contradicted the results obtained in other studies. The 15-DON concentration increased in all extruded samples, and the fermentation of the samples decreased them to acceptable levels. The capacity of fermentation to decrease mycotoxin levels in the food or feed samples may be caused by the binding capacity of LAB. Mycotoxin types and their initial concentrations in the food matrix, the physicochemical characteristics of this matrix, and the fermentation variables, such as temperature and duration, play a major role in determining the binding percentages [124].
