Analyzing meals and cakes | Nutrition research reveals yellow-seeded canola meal could be an effective alternative animal protein
University of Saskatchewan researchers are closer to understanding the value of yellow and brown canola seed as a livestock feed.
A one-year study on the effects of processing on the nutritional value of canola meal and press cake found significant differences between yellow and brown-seeded canola meal and brown-seeded canola press cake.
Katerina Theodoridou, a research fellow at the university’s animal and poultry science department, said the main difference is that brown-seeded canola press cake has high energy value, while canola meal, particularly the yellow-seeded kind, contains higher protein.
“When you make a diet for an animal, you need to have a balance between energy and protein,” she said.
“If you want more energy in the diet, you add press cake. If you miss protein, than you add canola meal.”
Press cake is a term for the solids left behind after pressing something to extract the liquid.
Researchers inserted a small nylon bag into the rumens of three dry Holstein cows, which allowed canola meal or press cake to be incubated for 48 hours.
What they found is that canola meal contains 35 to 44 percent crude protein and comes closest to meeting the nutritional profile of soybean meal, which is the industry standard.
Canola meal also has a relatively high amount of fibre because it contains 30 percent of the hull.
The researchers wrote in a recent article that yellow-seeded canola meal is higher in total digestible crude protein than brown meal and lower in total digestible fatty acid.
Brown canola press cake has lower total digestible crude protein and higher total digestible fatty acid than does meal.
The metabolic energy an animal uses for maintenance, pregnancy, weight gain and milk production is higher for brown canola meal than in brown canola press cake or yellow canola meal.
The U of S study found that yellow meal has higher crude protein and lower dietary fibre content than brown seed meal.
Press cake retains higher oil content because it doesn’t go through a solvent extraction process, but it is lower in crude protein.
The study also found that yellow-seeded canola produced results similar to soybeans.
Plant breeding selection programs are now targeting yellow-seeded varieties to improve the nutritional value of canola meal.
Theodoridou said yellow-seeded canola meal could be used an alternative animal protein to replace the common yet more expensive soybean meal.
“When you formulate, it’s always depending on value in the market at the moment,” she said.
“If one of these feeds is very expensive in this period of time, maybe they’ll replace it with something cheaper, like canola. This is the potential, at least.”