Application of Near-Infrared Spectroscopy for Rapid Analysis of Glucosinolate Content in Canola Meal

The objective of this project is to assess glucosinolates (GLS) qualitatively and quantitatively in canola meal (CM) using near-infrared spectroscopy (NIRS) calibration models.

The variation in chemical composition and nutritive value of CM among the processing plants across Canada has been demonstrated, and it was concluded that they are directly related to the processing conditions, mainly due to heat and moisture treatment. The highest variability has been observed in the lysine digestibility and in content of GLS, which are categorized as anti-nutritive factors (ANF) for poultry and swine. Therefore, a reliable technology is needed for rapid determination of CM quality and to facilitate an effective use of CM in poultry and swine diets.

Near-infrared spectroscopy has been used by the feed industry, however, CM analysis by NIRS is often restricted to very few measurements. Our research focuses on the development of advanced calibration curves for the direct and reliable assessment of CM quality. Use of NIRS to analyze GLS is a relatively new concept, and thus, requires development of advanced calibration curves for precision and reliability. Current research project involves determination of GLS content using gas chromatography (GC) that allows for NIR calibration for total GLS. A satisfactory correlation between determined GLS values to NIR spectra (r=0.768) using over 200 CM samples collected from all Canadian canola crushing plants was achieved. Samples of CM collected in Asia, Europe and Australia with higher GLS content were added to this calibration to improve the precision. Future research will focus on validation and further improvement of calibration. Already a well-balanced source of amino acids, successful analysis of GLS with NIRS could greatly improve potential of CM for higher inclusion in feed without adverse effects to livestock animals.

Key words: glucosinonates, near-infrared spectroscopy, canola meal.

Presented at the 2022 Animal Nutrition Conference of Canada. For information on the next edition, click here.