Figure 4.

Untargeted analysis example, high elevation tea. Spectral deconvolution and MS subtraction of hexanal, the target compound, ions and relative abundances (c) from the TIC (a) peak spectra (b) yields the residual spectrum (d) for mesityl oxide (e). Subtraction of the ions and relative abundances of both compounds results in baseline noise (f,g). The RIC chromatograms for hexanal (blue) and mesityl oxide (green) are also in (g). Experimental spectra were acquired in the range of 40–280 m/z, and therefore, ions below 40 m/z are missing from spectra (b–d,f).