Oil as a Hindrance to Oat (Avena sativa L.) Nutrient Fractionation: Leveraging Mass Spectrometry-Based Omics to Unravel Lipid Regulation for Functional Crop Improvement

Oats (Avena sativa L.) are a nutritionally valuable cereal crop known for their unique profile of bioactive compounds, including protein, β-glucan (BG), and avenanthramides (AVNs). However, industrial-scale processing and fractionation of these nutrients at an industrial scale are restricted by high oil content, limiting their application as functional food ingredients. While reducing oil content through targeted breeding may overcome these barriers, this strategy requires a deeper molecular understanding of lipid metabolism and its interplay with other nutrient pathways. In this review, we highlight the health benefits of key oat nutrients and discuss challenges in isolation techniques at an industrial scale. We then outline the canonical pathway for seed oil biosynthesis, supported by functional validation of genes encoding key lipid synthesis enzymes, and review studies linking regulatory enzymes to variations in oat oil content at gene and transcript levels. Finally, we highlight how mass spectrometry-based omics, particularly proteomics and lipidomics, can be used in breeding programmes to elucidate regulatory networks involved in oat oil biosynthesis and nutrient partitioning at the phenotype level.