Résumé
The major output of milling process of wheat grains is flour, bran represents the most important fraction of all by-products. Its content in fibres and micro-nutrients makes its enrichment interesting in breads and cereals products if no unfavourable changes in the sensorial properties are induced. In this research, we proposed to compare the volatile components of flour, fine and coarse brans to evaluate the potential impact of addition of bran in flour. The three fractions were obtained by using a micromill and the aromatic profile was characterized by GC-MS after SPME extraction. Numerous compounds due to lipid oxidation such as hexanal, 1-octen-3ol, nonanal, 2-heptanone were found in the three fractions. Limonene, a terpenic compound, characterized by sweet, citrus and peely odour was identified in the three fractions. This unexpected compound was already identified in flour. Eugenol, a phenolic compound, with spicy, clove like, woody odour and phenolic savour was only identified in the brans fraction. This compound is formed via the general phenylpropanoid pathway, including the conversion of coniferyl alcohol and specific enzyme. It could provide a specific marker of bran addition in flour.