How to substitute Rapeseed Oil in for Margarine
Multiply the amount of margarine in your recipe by 75 percent. For example, if your recipe calls for 1 cup of margarine, you would multiply that by 75 percent for a total of a 3/4 cup. If your recipe calls for 4 cups of margarine, multiply that by 75 percent for a total of 3 cups.
Measure out an amount of rapeseed oil equal to the number you determined. For example, if you calculated that 75 percent of the margarine in the recipe is 3/4 cup, measure out 3/4 cup of rapeseed oil.
Add the rapeseed oil to the recipe at the same time as you would have added the margarine. Cook the recipe as normal, optionally adding more eggs and sugar to the recipe.