Comprehensive nutritional analysis of 95 oat cultivars reveals large variability in nutritional profile: protein, starch, fat, β-glucan and fibre

Nutritional composition determines whether oats can deliver established health benefits like cholesterol reduction, which requires specific β-glucan thresholds unachievable by consuming a standard serving of typical commercial cultivars. Current yield-focused breeding overlooks the substantial nutritional diversity within the species, limiting consumer access to nutritional profiles optimised for different nutritional targets and leaving the potential for enhanced health outcomes untapped. This study characterised the nutritional composition of 95 Irish-grown oat cultivars and compared field (2024) versus glasshouse (2023) grown samples from 21 cultivars. Key components showed wide variation, with fat displaying the largest range and starch the most consistency, with concentrations ranging as follows: protein 11.5-22.9%, starch 47.2-65.3%, fat 2.4-10.0%, ash 1.4-2.9%, β-glucan 2.8-6.6%, and calculated fibre-rich fraction 8.5-26.9% (dry matter basis). Glasshouse-grown samples had significantly higher protein, fibre-rich fraction, and ash than field-grown counterparts (p < 0.001). These findings reveal untapped potential for breeding oats with targeted nutritional profiles to support dietary recommendations and food industry applications.