Originally Posted by SquirrellyCakes
dky, your margarines may be different in Australia too. Margarine should produce a less dense cake because it is made of vegetable oil and butter, well when the cake cools, the milk solids in the butter harden or set so you should techincally get a more dense cake with butter. But you won't get the taste from the margarine. Also many margarines have high moisture contents so you really need to use block or hard margarine unless using a commercial recipe adapted for Baker's margarine. Generally margarine though popular during the world wars when butter was next to impossible to buy, is not the fat of choice in cake baking and shouldn't be used as a substitute unless specifically called for.
If you don't like the density butter will create in a white or yellow cake, you are better off using a recipe calling for shortening or oil which actually makes the least dense cake.
Yes margarine is different here. I swap butter for margarine all the time, works a treat. Depending on how light i want the cake to be i will change the amount of rising powder i use and butter for margarine. Our margarines don't contain butter, they are *usually* vegetable oils, plus other additives, but not butter.