Natural Occurrence of Beauvericin and Enniatins in Corn- and Wheat-Based Samples Harvested in 2017 Collected from Shandong Province, China

Totals of 158 corn and corn-based samples and 291 wheat and wheat-based samples from Shandong province, China in 2017 were analyzed for five mycotoxins including beauvericin (BEA), enniatin A (ENA), enniatin A(1) (ENA(1)), enniatin B (ENB), and enniatin B(1) (ENB(1)) by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). BEA was the predominant toxin detected, followed by ENB, ENA(1), ENA, and ENB(1). Corn and corn-based samples were more easily contaminated by BEA with an average concentration of 65.26 µg/kg, compared with that in wheat and wheat-based samples (average = 0.41 µg/kg). Concentrations of BEA, ENA, and ENB(1) in corn kernels, flours, and flakes were significantly different (Kruskal–Wallis Test, p < 0.05), as well as for BEA, ENA, ENB, and ENB(1) in wheat kernels, flours, and noodles (Kruskal–Wallis test, p < 0.05). Furthermore, 59.5% (94/158) and 59.8% (174/291) corn- and wheat-based samples were co-contaminated by at least two mycotoxins, respectively. Positive correlations in concentrations were observed in corn between levels of ENA and ENB(1), ENA and ENB, ENA(1) and ENB(1), as well as in wheat between BEA and ENA, BEA and ENA(1), BEA and ENB, BEA and ENB(1), ENA and ENA(1), ENA and ENB, ENA and ENB(1), ENA(1) and ENB, ENA(1) and ENB(1), and ENB and ENB(1). These results demonstrate that co-contamination of BEA and enniatins (ENNs) in corn- and wheat-based samples from Shandong, China is very common. More data on the contamination of five mycotoxins in cereal and cereal-based samples nationwide are needed.