A comprehensive study on multi-mycotoxin screening, changes of mycotoxin residues and fungal community analysis from barley germination to malt.

Multi-mycotoxin contamination of barley reduces malt quality and also poses serious health risks to both humans and animals. Among the detected mycotoxins in barley, Fusarium and Alternaria toxins represent severe food safety issues due to their widespread prevalence and strong synergistic toxicity. In this study, the effects of Fusarium and Alternaria fungi and their related toxins were investigated using simulated malting process conditions for contaminated barley samples. The dynamic changes of the fungal community and their associated mycotoxins were analyzed via high-throughput sequencing and UHPLC-q-trap-MS/MS, respectively. The results showed significant differences in the fungal communities between barley grains and their associated malt samples. These differences were noted for the following: fungal community diversity, dominant flora and the fungal structures at phylum, genus, and family level. Additionally, significant changes in the levels of alternariol monomethyl ether, tentoxin, zearalenone, and 15Acetyl-Deoxynivelenone were observed (p < 0.05) during the malting process. These results provide valuable information for strategies aimed at controlling fungal infections and the presence of mycotoxins in malt, so as to ensure food safety and human health.