Learn the science behind:
There was a time when I thought a donut was a donut. Just a light brown fried ring with a glaze on top. Of course, there are a tons of glazes & fillings but, being non-American, I never realized there are quite fundamental differences between the doughs as well!
Leaving aside the glazes, there are two very different donut types: yeast and cake donuts. As the name says, the yeast donuts use yeast, whereas the cake donuts do not. The cake donuts have more of a cakey structure (hence the name…) and are made quite differently.
What is a cake donut?
A cake donut is a donut that’s made without yeast and instead uses baking powder or baking soda to puff up into the nice round donut shape. A cake donut is denser than a yeast donut and has a more crumbly bite than a yeast donut. A yeast donut contains more fat in the recipe (the final fat content though also depends strongly on how it’s been fried).
Cake donuts tend to be a little more crispy on the outside than yeast donuts and according to some, they lend themselves better for dunking in a drink than yeast donuts do (although I would never dunk my donut). The cake donut is younger than its yeast counterpart though, since it could only develop with the invention of baking powder & baking soda whereas humanity has been using yeast a lot longer.
Is a cake donut baked or fried?
Cake donuts can be made with both frying in oil or baking in the oven. Which one you use will depend on the recipe you use. Not all recipes are suitable for both methods. Since frying in oil goes a lot faster (oil transfers heat more efficiently) it can handle a different bake than baking in the oven. On the other hand, when you’re baking your donuts in a donut baking tray, your donut batter can be a lot more liquid (it doesn’t have to keep its shape as much). I would challenge whether a baked donut doesn’t just become a muffin/cupcake in the shape of a donut, but I guess opinions differ.
Making cake donuts is quick
A cake donut is leavened with baking powder and/or baking soda. It does not need any yeast. As a result, it does not have to proof for the yeast to do its work. That means making cake donuts is a lot faster than making yeast donuts. You can make the batter and almost immediately fry it.
No gluten formation – Quick mixing
Not only can you skip proving the dough, you don’t even to knead the dough either. Kneading a dough is done to develop the gluten in a dough. This is very desirable for bread and yeast donuts since it helps to give some stretch to that dough and helps hold on to the air made by the yeast. However, we do not want gluten in cake donuts (as is the case for muffins, cakes & scones). Therefore, as soon as the flour is in your bowl, limit mixing as much as you can.
Shaping a cake donut
A yeast donut uses a dough that you can easily shape into a donut. It’s more similar to a very light bread. Thanks to the gluten it will hold up well. However, since we don’t have those gluten in a cake donut we have to use other methods.
Cookie dough style
The first method is to use a donut dough that is very thick. It looks more like a cookie dough once you’ve added all the ingredients than like a cake batter. This type of dough is ideal for cutting out your donut shapes. You will find that these recipes (including the one at the bottom of the post) ask you to chill your dough (just like some cookie recipes do!). You have to do this to ensure the dough firms up well and can be cut more easily.
Piping or scooping
Other recipes will give a thinner, more liquid batter which is more similar to a thick cake batter than a cookie dough. These recipes aren’t suitable for cutting out your donut shape. They will lose their shape and your can’t really pick them up to throw them into the oil. Instead, you will need to either use a scoop (bit like with a Dutch oliebol) or a piping bag (more similar to a churros) to shape them and then quickly fry them.
Frying a cake donut
A cake donut barely contains any air at the moment it enters the fryer. It is still very dense and almost all the expansion will have to occur during frying. Apart from the air bubbles that need to be formed, you want the eggs and flour to cook and moisture to evaporate (to create a crispy crust).
The trickiest thing with donuts is to get that center cooked, while not burning the outside. For cake donuts there are a few tricks to do so, but again, these depend on the type of batter you’ve made!
As with anything you fry: controlling the temperature of the oil will make your life a lot easier. A constant oil temperature means that every donut will take about the same time to cook.
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A good temperature is one that doesn’t burn the outside of your donut before the inside is done. If that happens, your temperature is too high. On the other hand, you don’t want the center to cook long before your donut has a nice brown colour. If that happens, your temperature is too low and your donut may turn out dry or soaked full of oil.
Using colour to fry cookie dough style donuts
While you bake your donut it doesn’t just get cooked. It also develops a lot of flavour and colour. This is due to the Maillard reaction. You will smell the flavour and clearly see the colour.
You can use the amount of browning to check whether the donut is done. As long as your frying temperature is constant you can bake your first donut to the colour you want it. Check whether it is cooked and if it tastes good (not over baked, nor raw), then you can cook the rest to the same colour. Especially when making a new recipe it is always good to do this quick check.
Some notes on cookie dough style donuts
The dough of this type of cake donut is very dense. It is denser than oil. Which means that when you put these donuts to fry in the oil they will sink to the bottom!
As they heat up in the oil and as the baking soda gets activated, air bubbles are formed and the donut expands. As a result, the density of the air decreases! Once it’s become airy enough, it will float back to the top of the oil. This doesn’t necessarily mean though that the center is cooked, it’s just step one. From here on you can either bake on sight (colour of the donut) or use the trick we describe below.
Using cracking to check on your frying donut
If you’re making donuts that are very dark by themselves (like the chocolate ones at the bottom of the post). You can’t use colour to determine whether the donut is ready so you have to rely on other cues.
For the cookie dough donuts that starts once your donut has floated to the top. You now have to watch for cracks forming on the top of the donut (a bit like a crack on top of a cake, but then smaller). As soon as you see those you can be quite sure that the inside of the donut is actually cooked.
Flip the donuts at this point and leave them in for a short while to cook the outside of the other side. Remember, the center is already cooked, so you really only need that top layer to cook.
Bon appetit, You’re either a cake doughnut person or a yeast one, April 26, 2016, link
Food52, Cake Doughnuts 101: The completist’s guide to shaping, flazing, frying (& baking) your own, August 19, 2016 (by Eiron McDowell), link