Influence of glucosinolates and a tentative high‐molecular detrimental factor on the nutritional value of rapeseed meal

Feeding experiments with mice suggest that high‐molecular weight compounds in rapeseed meal without direct relationship to glucosinolates have a detrimental effect on the nutritional value of the meal. This effect is precluded by treatment with ethanol or upon heating. Ethanol extraction improves the nutritional value of the residue as a result of the removal of non‐essential nitrogenous compounds. The nutritional value of the seed meal of the cultivar Bronowski was superior to that of the high‐glucosinolate meal. A freeze‐dried ethanol extract of the high‐glucosinolate cultivar Sv Rigo was toxic to mice, especially when fed in combination with myrosinase, in contrast to ethanol extract from the low‐glucosinolate cultivar Bronowski. A decrease of the glucosinolate content to a level below that of Bronowski did not effect the growth response of mice.