what happens when you whisk sugar with oil?

Question

So far I have tired four different carrot cakes recipes, everything ended up too oily (The oil drips from the cake when pressed). I was wondering and found all of these recipes calls for "whisking sugar with oil until the sugar dissolves" as the very first step. I am sure, I am missing some basics here, since I don't know what is the consistency needed.

Can anyone shed light on what happens when you whisk sugar with oil? Like creaming sugar and butter to incorporate air into the mixture. What is the concept behind it? How the consistency should look?

I am using 135g white caster sugar and 100ml sunflower oil, if this information is of any help.

Answer 1

Oil doesn't really dissolve sugar. The main purpose for the mixing is that in many recipe techniques, especially the muffin method, sugar is treated as a wet ingredient. By premixing the wet ingredients, and premixing the dry ingredients, when the two are combined, you require much less additional mixing to get a homogeneous total batter.

Creaming sugar into butter or shortening helps leavening because the sharp edges of the sugar crystals cut air into the solid fat medium, essentially creating a foam. This then serves as seed air bubbles for the chemical leavening to expand. This effect cannot occur with liquid oils.

Many carrot cakes are pretty dense and oily, although I don't think they should drip when pressed. You might have something else going on in your recipes or technique.

Answer 2

You get a slurry. Depending on the ratio of oil to sugar, you can end up with oil occupying the "voidage" between sugar crystals (think about damp sand) or sugar crystals dispersed in a body or oil. If you have not much oil (determined by crystal size), capillary action would produce a stable "damp" mixture. Again, depending on the type of oil, and type and particle size of the sugar, the suspensions may settle out into two layers over time. Based on a very rough estimate, your 135g in 100ml should yield a very dense suspension, much like a gritty paste.

As pointed out by SAJ14SAJ, sugar is practically insoluble in oil. Your recipes are confusing dispersing with dissolving. You will always end up with a 2-phase 2-component soild-liquid slurry, unlike dissolving (2-component, 1-phase). With butter however, there is always some water in it to dissolve some sugar. After whisking, you end up with a 4-compenent 4-phase (oil, sugar solid, sugar-water solution, air) emulsion (strictly speaking not a foam) or 4-component 3-phase if there is there no excess sugar beyond what is soluble in the water inside the butter. The main difference is that by heating the butter, you will increase the amount of dissolved sugar and vice versa. With just oil and sugar, temperature change would make no difference to the slurry other than the oil viscosity.

I doubt very much if this sugar-oil step is the cause of the dripping oiliness of your cake. The recipes are clearly wrong about dissolving and extending from that, the hope of better mixing using a sugar-oil slurry is flawed. Efficiency of mixing sugar into your dough is about shear force, whether you add oil and sugar separately or pre-mixed would make very little difference, these ingredients still go in as two separate phases. The oil would add some lubricity regardless to aid mixing. If the sugar were actually dissolved in a solvent, one phase, that would make a difference.

Answer 3

i make carrot cake. My recipe does not call for whisking the sugar and oil together. It says to beat together.
try that , it might make a difference.