Canola meal is produced from the rapeseed plant, a relative of broccoli and mustard. Natural rapeseed contains glucosinolates, which make feed unpalatable, and erucic acid, which is toxic to animals. These anti-nutritional factors are heat-stable, and therefore, cannot be removed by heat-treating rapeseed. Rapeseed, which is low in both glucosinolates and erucic acid, has been produced by hybridization, and is called canola in Canada and the United States and 00-rapeseed in Europe. Oil can be removed from canola and rapeseeds via solvent extraction or mechanically expelling. The solvent extraction process results in production of canola meal or 00-rapeseed meal and mechanical expelling of oil results in production of canola expellers or 00-rapeseed expellers.
The objective of this study was to compare the chemical compositions of canola meal from North America and 00-rapeseed meal from Europe and to compare the composition of 00-rapeseed meal and 00-rapeseed expellers. Ten samples of canola meal were collected from crushing plants in North America, and eleven samples of 00-rapeseed meal and five samples of 00-rapeseed expellers were collected from crushing plants in Europe. The samples were analyzed for energy, fat, sugar, starch, fiber, crude protein, amino acids, and minerals.
Energy and fat
There was no difference in energy or fat concentration among canola meals and 00-rapeseed meals (Table 1), but 00-rapeseed expellers contained more(P < 0.05) dry matter, gross energy, and fat than 00-rapeseed meal. Expelling oil is less efficient than solvent extraction and leaves more oil in the rest product, which is the reason for the greater concentrations of fat and energy in 00-rapeseed expellers compared with 00-rapeseed meal.
Table 1. Energy and fat concentration of canola meal, dry-matter basis
| Location | 00-Rapeseed | ||||
| Item | North American Canola Meal | European 00-Rapeseed meal | Expellers | Meal | |
| n=10 | n=11 | n=5 | n=11 | ||
| DM (%) | 90.23a | 88.94b | 91.83a | 88.94b | |
| GE (kcal/kg) | 4708 | 4734 | 5143a | 4734b | |
| Fat (%) | 4.14 | 4.34 | 12.56a | 4.34b | |
a-b Means within a row lacking a common superscript letter differ (P < 0.05).
Carbohydrates
00-rapeseed meal contained less (P < 0.05) raffinose and crude fiber, and more (P < 0.05) sucrose, than canola meal (Table 2). Otherwise, there was no difference in the concentrations of sugars, starch, or fiber between canola meal and 00-rapeseed meal.
00-rapeseed meal contained more (P < 0.05) sucrose, crude fiber, NDF, and lignin than 00-rapeseed expellers. Otherwise, there was no difference in the concentrations of sugars, starch, or fiber between 00-rapeseed meal and expellers.
Table 2. Carbohydrate concentration of canola meal, dry-matter basis
| Location | 00-Rapeseed | ||||
| Item | North American Canola Meal | European 00-Rapeseed Meal | Expellers | Meal | |
| n=10 | n=11 | n=5 | n=11 | ||
| Fructose (%) | 0.04 | 0.11 | 0.14 | 0.11 | |
| Glucose (%) | 0.04 | 0.07 | 0.36 | 0.07 | |
| Sucrose (%) | 6.87b | 7.76a | 6.86b | 7.76a | |
| Maltose (%) | 0.02 | 0.01 | 0.02 | 0.01 | |
| Raffinose (%) | 0.51a | 0.34b | 0.30 | 0.34 | |
| Stachyose (%) | 1.55 | 1.70 | 1.43 | 1.70 | |
| Verbascose (%) | 0.00 | 0.00 | 0.00 | 0.00 | |
| Crude Fiber (%) | 9.70a | 8.17b | 6.36b | 8.17a | |
| ADF (%) | 20.49 | 21.72 | 19.47 | 21.72 | |
| NDF (%) | 33.60 | 33.80 | 27.04b | 33.80a | |
| ADL (%) | 8.65 | 8.91 | 7.79b | 8.91a | |
a-b Means within a row lacking a common superscript letter differ (P < 0.05).
Protein and amino acids
Crude protein and total amino acid concentration did not differ between canola meal and 00-rapeseed meal (Table 3). The concentrations of cysteine, glutamic acid, and proline in canola meal were greater (P < 0.05) than in 00-rapeseed meal, but the concentrations of other amino acids did not differ between canola meal and 00-rapeseed meal.
00-rapeseed expellers contained less (P < 0.05) crude protein, threonine, alanine, glycine, and tyrosine than 00-rapeseed meal, which is likely due to the greater fat content in expellers than in meal.
Table 3. Crude protein and amino acid concentration of canola meal, dry-matter basis
| Location | 00-Rapeseed | ||||
| Item | North American Canola Meal | European 00-Rapeseed Meal | Expellers | Meal | |
| n=10 | n=11 | n=5 | n=11 | ||
| Protein (%) | 41.42 | 40.70 | 38.76b | 40.70a | |
| Total AA (%) | 35.98 | 34.60 | 32.69 | 34.60 | |
| Indispensable AA (%) | |||||
| Arginine | 2.37 | 2.25 | 2.15 | 2.25 | |
| Histidine | 1.09 | 1.04 | 0.98 | 1.04 | |
| Isoleucine | 1.65 | 1.58 | 1.49 | 1.58 | |
| Leucine | 2.82 | 2.70 | 2.53 | 2.70 | |
| Lysine | 2.23 | 2.17 | 2.07 | 2.17 | |
| Methionine | 0.78 | 0.76 | 0.70 | 0.75 | |
| Phenylalanine | 1.59 | 1.53 | 1.44 | 1.53 | |
| Threonine | 1.64 | 1.63 | 1.52b | 1.63a | |
| Tryptophan | 0.50 | 0.47 | 0.45 | 0.47 | |
| Valine | 2.12 | 2.06 | 1.95 | 2.06 | |
| Dispensable AA (%) | |||||
| Alanine | 1.75 | 1.69 | 1.57b | 1.69a | |
| Aspartic acid | 2.80 | 2.81 | 2.67 | 2.81 | |
| Cysteine | 0.91a | 0.86b | 0.82 | 0.86 | |
| Glutamic acid | 6.37a | 5.95b | 5.59 | 5.95 | |
| Glycine | 2.01 | 1.96 | 1.83b | 1.96a | |
| Proline | 2.37a | 2.22b | 2.09 | 2.22 | |
| Serine | 1.39 | 1.35 | 1.29 | 1.35 | |
| Tyrosine | 1.11 | 1.09 | 1.01b | 1.09a | |
a-b Means within a row lacking a common superscript letter differ (P < 0.05).
Minerals
Canola meal contained more (P < 0.05) magnesium and molybdenum than 00-rapeseed meal, but 00-rapeseed meal contained more (P < 0.05) phosphorus, phytate-bound phosphorus, potassium, and zinc than canola meal. The concentrations of calcium, manganese, copper, and sulfur did not differ between canola meal and 00-rapeseed meal.
00-rapeseed meal contained more (P < 0.05) phosphorus, phytate-bound phosphorus, potassium, and zinc than 00-rapeseed expellers, but rapeseed expellers contained more (P < 0.05) magnesium and molybdenum than 00-rapeseed meal. The concentrations of calcium, iron, manganese, copper, sodium and sulfur did not differ between 00-rapeseed expellers and 00-rapeseed meal.
Table 4. Mineral concentration of canola meal, dry-matter basis
| Location | 00-Rapeseed | ||||
| Item | North American Canola Meal | European 00-Rapeseed Meal | Expellers | Meal | |
| n=10 | n=11 | n=5 | n=11 | ||
| Ash | 7.93 | 7.78 | 7.93 | 7.78 | |
| Calcium | 0.85 | 0.83 | 0.85 | 0.83 | |
| Phosphorus | 1.14b | 1.22a | 1.14b | 1.22a | |
| P in phytic acid (%) | 0.90b | 0.98a | 0.90b | 0.98a | |
| Iron (ppm) | 260.59 | 187.05 | 260.59 | 187.05 | |
| Magnesium | 0.62a | 0.51b | 0.62a | 0.51b | |
| Manganese (ppm) | 74.81 | 67.76 | 74.81 | 67.76 | |
| Copper (ppm) | 6.79 | 5.99 | 6.79 | 5.99 | |
| Sodium (ppm) | 572.67 | 443.76 | 572.67 | 443.76 | |
| Potassium | 1.29b | 1.46a | 1.29b | 1.46a | |
| Sulfur | 0.80 | 0.84 | 0.80 | 0.84 | |
| Molybdenum (ppm) | 1.01a | 0.79b | 1.01a | 0.79b | |
| Zinc (ppm) | 60.25b | 71.57a | 60.25b | 71.57a | |
a-b Means within a row lacking a common superscript letter differ (P < 0.05).
This report is based on unpublished data from T. Maison and H. H. Stein.