Creaming butter is one of the most basic techniques in baking. Most cakes and cookies would require the butter to be well creamed so as to achieve a tender fluffy baked product. Well creamed butter is especially important in cakes.
To cream butter well, the butter has to be first softened at room temperature. How do we know if the butter is soft enough? To test the softness, use a butter knife to cut into the butter. When the butter offers little resistance, it is soft enough to cream. Do not over soften the butter such that it turns oily. The butter will not cream well.
Butter is usually creamed with castor sugar. Castor sugar is used as it has fine grains and hence a larger surface area. When the butter is creamed with the castor sugar, the sugar grains cut through the butter and aerates it, creating air bubbles. These air bubbles help cakes to rise and maintain a light texture. Icing sugar is not recommended for creaming as it does not aerate the butter well. On the other hand, using coarse sugar will result in baked products with coarser texture.
Firstly, beat the butter on low speed briefly so that it becomes creamy. Add in the sugar and continue beating on low speed to combine. When the sugar is evenly distributed, increase speed to medium and continue beating.
Initially when the sugar is added, the texture of the butter is somewhat sandy. As we continue to beat the butter, the sugar seems to dissolve into the butter. In the midst of the beating process, stop the beater and use a spatula to scrape the sides and bottom of the bowl to allow stray sugar and butter to be incorporated.
Further beating of the butter will result in an increase in volume and the butter will become creamy and less sandy. Notice that the colour of butter will start to pale.
Finally, when butter is properly creamed, the colour will be off-white. The resulting texture is thick and creamy like mayonnaise and is only slightly sandy/gritty since the sugar may not dissolve completely. At this point, the volume has increased noticeably. Do not continue to cream the butter or it may soften and all efforts will be wasted.
In recipes where the amount of sugar far outweigh the amount of butter, the thick and creamy mayonnaise texture would not be possible to achieve. The volume of creamed butter in this case would still increase but will be far more sandy rather than creamy.
Creaming of butter can be done with a wooden spoon, a handheld beater or a stand beater.
1) Baking911: Creaming Butter
2) Epicurious: Video on creaming butter