Evaluation of groat breakage during dehulling

Groat breakage is an important factor affecting milling yield. Variation for breakage exists among varieties but it is not clear what physical and/or chemical characteristics are associated with this variation. One hundred and thirteen oat lines were dehulled using a laboratory-scale, constant speed impact dehuller. Breakage was measured as the mass of broken groats in the dehulled sample. Biplot analysis (www.ggebiplot.com) was used to investigate the relationships among groat protein, oil and b-glucan, groat size (mass and length), difference in kernel and groat length and proportion of undehulled kernels. Breakage was most closely associated with kernel size (both mass and length). There was a weak but positive relationship between groat content and breakage. â-glucan and oil content were negatively but weakly associated with breakage. The difference between kernel and groat length was not associated with groat breakage, but was closely associated with the proportion of undehulled kernels. It is clear that the dehuller speed must be adjusted to account for differences in groat mass.