A MS Nose interface (Micromass, Manchester, UK) fitted to a Quattro Ultima mass spectrometer (Milford, Waters, UK) was used for the static headspace analysis of bread samples. 50 g samples were placed in 40 mL vials fitted with a one port lid. After a 30 min equilibration period at room temperature (20 C), the headspace was drawn into the APCI-MS source at a rate of 5 mL/min. The samples were analysed in full scan mode, monitoring ions of mass to charge (m/z) ratios from 20 to 200. The intensity of these ions was measured at cone voltage of 50 V, source temperature of 75 C
and dwell time of 0.5 s. All analyses were run in triplicate and were based on the methods of Gan, Soukoulis, and Fisk (2014).