Sugar definitely is one of the most complex and fascinating ingredients in the kitchen. It sweetens your food, but can also be used to create a whole lot of different textures and structures in your food! Sugar helps thicken a jam, form the brittle texture of a hard candy and create a light and stable egg white foam.
When using sugar in a fruit pie, it helps to break through that tart or sour flavour from fruits you’re using. This is especially helpful when using a tart fruit such as cranberries. But, the sugar can also provide a whole new texture to your pie. By controlling how and if the sugar dissolves in your filling you can create either a thick fruity filling, or something a lot more crunchy.
This time, we’re aiming for the second option: using sugar in a (cranberry) pie to get that crunchy texture!
Sugar dissolves really well
One of the most important of features of sugar (we’re talking about regular sugar here, with the chemical name sucrose) is that it dissolves well in water. If you add some sugar to a hot cup of tea, that sugar will be invisible within a matter of seconds. The sugar hasn’t disappeared, it’s just that the sugar crystals have broken down into individual molecules and dissolved in the water. These molecules are too small to see and float throughout your tea.
If you would keep on adding sugar to your hot tea, at some point the sugar won’t dissolve anymore. Instead, you’ll end up with a lump of sugar crystals at the bottom of your cup of tea. There are now so many sugar molecules floating through the tea, that it has become saturated. There is literally no place anymore for the sugar to dissolve.
How much sugar can dissolve in the water depends on the temperature of that water. Hotter water can contain more sugar than cold water can. When you make any type of sugar candy you use this to your advantage to make a range of textures.
Controlling sugar dissolution in fruit pie
In some cases though you do not want the sugar to dissolve. This is especially the case if you want to create some crunch from the sugar in your food. The best way to prevent (all) the sugar from dissolving is to just add less water. If the amount of water is very low, the sugar crystals will just remain as is.
Choosing the type of fruit
You can use this to your advantage when making fruit pies. If your fruit pie filling contains a lot of moisture, the sugar will dissolve. If you mix your apples with sugar (And some spices) for an apple pie filling, you end up with this scenario. The sugar doesn’t all dissolve when mixing the apples and sugar. However, once the apples cook they release a lot of moisture that remains trapped within the pie. As a result, the sugar that is present dissolves in this moisture. Generally, fruits that release a lot of moisture such as pears, apples, apricots, etc. are very suitable for making such a smooth sweet pie filling.
Controlling moisture release
Some fruits simply release more moisture than others. However, you can control how much moisture is released to some extent. Cutting fruit in smaller pieces makes it a lot easier to break down fully and release moisture. By using larger pieces of fruit or by using whole fruits you reduce this substantially.
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If you don’t cut cranberries for instance they won’t lose their moisture as quickly and as easily. If the moisture that is released first has time to evaporate before the whole filling gets soggy, you will end up with a very different filling texture than if you would have cut up all the cranberries.
Letting moisture evaporate
No matter what you do to try and prevent a lot of moisture loss from your fruit, it will always happen to some extent. All fruit loses its firm texture when you heat it and as such releases water. It is even worse for frozen fruit since freezing it has already broken down that internal strong texture! However, you can prevent all this moisture from staying in your pie. The first and most effective is to reduce the height of your pie.
If you use the same amount of filling, but reduce the height of your filling, you will have to make a larger surface area of the pie. Because of this increased surface area, it is easier for moisture to escape. In the hot oven, it is pretty easy for moisture on the top to evaporate if it is not held back by anything such as a crust or another layer of filling on top.
The other method, that we quickly alluded to, is to not cover the top of the pie. The moisture should be able to escape!
When you’re designing your next recipe, keep these simple lessons in mind. It will help you to create exactly the texture that you’re looking for! Below, we’re preventing the sugar from dissolving to create that crunchy filling.
Sweet pie dough
- You can use any sweet pie dough (about 400g of total dough)
- 320g cranberries
- 75g pecans, roughly chopped in pieces (you want it to give crunch)
- 100g sugar
- Prepare your sweet pie dough. Roll it out into a tin with low sides (about 2cm/1 inch in height). You can use a small sheet pan or a round pie tin.
- Tip: if you have left over dough, roll it out thinly and cut into small shapes, not strips, save them until step 5 or bake them separately on a tray as cookies on the side.
- Pre-bake the dough according to recipe (if you don't there's a good chance the cranberries will make it soggy).
- Mix the cranberries, sugar and cranberries into a bowl. There should be enough sugar to cover the cranberries in a thin layer and some loose sugar remaining.
- Add the filling into the tart shell. If you have a few decorative pieces of dough, place these on top. However, be caraeful to limit yourself and keep the majority of the filling open to the air to ensure you get a crunchy filling.
- Place back in the oven at 160C (350F) for another 20-30 min. The cranberries should have softened and the filling will have sunk down a little.
The sugar will not all dissolve in the fruits. When the cranberries are cooking here they'll soften and let go of moisture. However, this still isn't enough to dissolve all the sugar since the majority will be able to escape. This ensures that the sugar stays nice and crisp!