Effect of processing conditions on the nutritive value of canola meal and presscake. Comparison of the yellow and brown-seeded canola meal with the brown-seeded canola presscake.

BACKGROUND

Canola, unlike traditional rapeseed, contains low levels of 'erucic acid' and 'glucosinolates'. Canola's industrial processing generally involves separation of the seed into an oil and a meal fraction whereas the intermediate product is called presscake. The objective of this study was to determine the effect of processing conditions on the nutritive value for ruminants and compare the yellow (Brassica juncea) (CM_Y) and the brown-seeded (B. napus) (CM_B) canola meal and the brown-seeded (B. napus) (CPC_B) canola presscake.

RESULTS

Either extract was higher (P<0.05) for CPC_B than for CM_Y and CM_B. CM_Y had a higher (P<0.05) PB2 and PC compared to CM_B. Truly digestible fractions, except fatty acid, were lower (P<0.05) for CPC_B. Effective protein degradability of CM_Y was lower (P<0.05) compared to CM_B or CPC_B. In vitro protein intestinal digestibility for CM_Y was higher (P<0.05) than for CM_B or CPC_B.

CONCLUSION

CPC_B had lower protein but higher oil content than canola meal and is a potential high-energy supplement source for ruminants. CM_Y had higher crude protein, digestible and metabolizable energy values and low fiber than CM_B. In plant breeding, selection programs are geared towards yellow-seeded varieties in order to improve the nutritive value of canola meal.