RAPESEED REFERENCE MATERIALS WITH CERTIFIED GLUCOSINOLATE AND SULPHUR CONTENTS

The presence of glucosinolates (GSL) in rapeseed cake reduces its palatability to farm animals and is associated with interference in thyroid function and with other disorders. The European Community actively encouraged the production of rapeseed varieties having low glucosinolate contents by paying a premium when the GSL content of the seed is less than 25 umol/g. The project was set up to provide rapeseeds with known glucosinolate contents as a means of verifying the various methods (HPLC, GLC, etc) used both in oilseed process plants and in the official laboratories. A series of rapeseeds with certified sulphur content was required to provide a common basis for the calibration of a rapid X-ray fluorescence (XRF) method for determination of total GSL. Three rapeseed reference materials (RM) were certified for their total GSL (umol/g) and sulphur (mg/g) contents, respectively, and are as follows: RM number 366: 12.1(+/-0.8) and 3.41(+/-0.12); RM number 190: 25.5(+/-0.9) and 4.93(+/-0.15); RM number 367: 102(+/-3) and 10.5(+/-0.4).