What’s in the meal?

Be clear on oil content of the oilseed and the cake. Crushing the whole seed rather than dehulling it before pressing increases the fiber levels. All of the numbers describing the various oilseeds on the next page are the oil, or fat, content of the meal. The words fat and oil are interchangeable. Keep in mind that any variability in an oilseed crusher’s efficiency and effectiveness in removing the oil will affect factors such as feed ration recommendations and shelf life. For example, canola seed is about 40 percent oil, based on methods that extract virtually all the oil, usually solvent extraction.

Oil extraction machine

However, if cold pressing canola gets only 70 percent of that 40 percent, the amount of oil left in the cake is more than what a processor that removes 85 percent of the oil would leave.
Meals of the oilseeds in the brassica family contain glucosinolates, which are organic compounds that function as natural pesticides and give brassicas their bitter taste. Glucosinolates have anti-nutritional qualities that block absorption of some nutrients. Mustard meal has very high levels of these compounds. Camelina and canola have much lower levels, making them far more suitable for feeding.
Soybeans contain trypsin inhibitors that need to be deactivated by cooking before animals can derive the full value of the protein in the meal (Van Gerpen, 2008). There is a large body of litera-ture on what meals are best suited for ruminant or monogastrics like swine and poultry animals.