Fungal contamination of stored cereals represents a major global challenge, contributing to food losses, reduced grain quality, and the formation of harmful mycotoxins that threaten food and feed safety.

Wheat is particularly vulnerable to infection by Fusarium species, especially when grains are stored under conditions that are not optimally dry or cool.

The most common mycotoxins found in stored wheat grains are deoxynivalenon (DON) and zearalenone (ZEN) from Fusarium species such as F. graminearum.

It is estimated that 60–80% of the global crop supply is contaminated with mycotoxins, with 20% of crops exceeding the European Union'slegal food safety limits. 

Recent research suggests that plants actively respond to pathogen attack by producing specific volatile signals. However, the biological origin of many VOCs detected in infected grains remains unclear — whether they are emitted by fungi or produced by plant defence mechanisms.

Stable isotope labelling with 13C-labeled substrates provides a powerful tool for tracing metabolic processes and determining the microbial or plant origin of emitted VOCs.