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Feruloylated arabinoxylans are a major hemicellulosic component of whole grains’ dietary fiber complex. Their xylan backbones are substituted with L-arabinose and oligosaccharides, and some of these substituents are ester-linked with monomeric <i>trans</i>-ferulic acid, forming feruloylated side chains (FSC). Both increased FSC quantity and complexity (degree of polymerization of sugar moiety) potentially reduce feruloylated arabinoxylans’ enzymatic digestibility. FSC profile differences could therefore affect, among others, the prebiotic potential of feruloylated arabinoxylans from different wholegrain sources and outcomes of xylanase treatments during wholegrain bread baking. We have developed and validated two FSC-screening methods enabling quantitative FSC profile comparison of cereal grain materials. The three most abundant FSC in cereal grains were isolated in preparative quantities as standard compounds for method development. For application to cereal grain materials (insoluble fibers from whole grains), FSC were semi-selectively released (50 mM trifluoroacetic acid, 2 h, 100°C), and the hydrolysates were cleaned up with C18-SPE. Liberated FSC were either quantified via two-dimensional NMR (HSQC) or reduced to their sugar alcohols with NaBH4 and separated and quantified with LC-DAD-MS/MS. The determined FSC concentrations showed good correlation between the two methods. Sample preparation time was shorter for the HSQC-NMR method, but the LC-DAD-MS/MS method was more sensitive. Up to 93% of the total esterified monomeric ferulates were captured in the FSC profiles, confirming the significance of these compounds to the global arabinoxylan structure. Unique profiles emerged for the different grains: for example, oats had low overall FSC concentrations but high profile complexity, while maize displayed both high FSC concentrations and profile complexity.