Content of nutrients and lignans in roller milled fractions of rye

Rye grain was roller milled into six flour fractions (607 g kg-1), a short (341 g kg-1) and a bran (52 g kg-1) in a Buhler laboratory mill. In the different flours (F1-F6) a progressive increase in ash (4-13 g kg-1), crude protein (39-87 g kg-1) and crude fat (5-17 g kg-1) concentration was found and a corresponding decrease in starch (853-699 g kg-1) concentration. Total dietary fibre (55-109 g kg-1) constituents and the lignans, matairesinol (0.05-0.22 mg kg-1) and secoisolariciresinol (0.21-0.38 mg kg-1), showed a different distribution with a maximal concentration in F5. The short and bran had higher concentrations of ash, crude protein, crude fat, dietary fibre components and lignans but a lower concentration of starch than the flours. Compared to the short, the bran contained more of all constituents analysed except mixed-linked β-glucan and starch. A very high proportion of total dietary fibre components of the rye, such as arabinoxylan (72%), cellulose (76%) and Klason lignin (79%) as well as of matairesinol (87%) and secoisolariciresinol (73%), was found in the short and bran together.