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Making Perfect Puff Pastry – Science of Flaky Layers
Making puff pastry sounds very daunting to a lot of home bakers. Folding and folding of doughs, butter sticking out, hours and hours of work. You might have seen contestants struggling with it on tv baking shows or you’ve read through instructions and become overwhelmed immediately.
And, in all honesty, why make it, when you can buy it? That changes though, once you’ve bought (too cheap) puff pastry that ruins your pie or cookie that you’re trying to make (which definitely happened to us!). Once you’ve made it yourself and know how good it can taste, you will either not go bake to store bought, or you’ll focus on finding a better place to buy good quality frozen puff pastry!
In reality, making puff pastry is not as hard as it seems. You just need to make sure you plan ahead, it will take a couple of hours to make it, although most of that can be spent relaxing on a couch or making other food!
What is puff pastry?
As the name says: puff pastry is pastry that puffs. More precisely, it puffs while baking in a hot oven into hundreds of thin layers. Puff pastry is actually very similar to a croissant dough, the main difference being that puff pastry does not contain any yeast, which makes it a lot easier to store and handle since you don’t have to watch the yeast.
If you look closely at a well cooked piece of puff pastry you can identify a lot of different layers of very thin flaky pastry, with layers of air in between. Even in uncooked pastry you can see those layers when you look straight up the sides (see photo below). Each of those layers consists of a thin layer of dough (mostly flour + water) sandwiched between two layers of fat (often butter or margarine). The fat prevents the dough layers from interacting with one another, so they can’t form one large structure, as would happen when you make a bread for instance.
When you put puff pastry in the oven, the fat in between those dough layers melts and it will sit in the actual dough itself. Also, moisture, from the butter as well as from the dough, starts evaporating as the pastry becomes warmer. The air can easily sit in between those dough layers since they weren’t holding onto one another anyway. As a results, the space between the layer expands and you get those air pockets.
Fat in puff pastry
Puff pastry contains a lot of fat, it needs the fat to form all those layers. A commonly used fat is butter, but margarine (the hard one, not spreadable margarine) is a good alternative. The fat content in puff pastry is at least half the weight of the flour, but the ratio of flour to fat can be as high as 1:1.
How to make puff pastry
We’ve got a recipe for puff pastry at the bottom of this post, walking you through all the instructions to do it at home. The process for making it at home is very similar to how manufacturers do it (as we will see later), although they will automate part of the process.
Those layers are the most important part of puff pastry. You make them by folding a dough with fat inside several times. In order to create them you start by making a simple dough of water and flour (and a few other ingredients, this depends on the recipe). This dough should be nice and flexible since you’ll be stretching it quite a bit as you go.
Next you need to incorporate the fat. There are several techniques to do this. For instance, you can lay a slab of fat on top of a rolled out piece of dough (the technique we use in the recipe at the bottom of this post). Another technique is to use pieces of butter that you spread around the dough, or you can even use a food processor to mix the (frozen) fat into the dough. The most important bit of this step is to ensure that the fat is evenly distributed throughout the dough, while not melting. Now that the fat is in you will have dough/fat/dough layers in your dough, although you might not always see those clearly.
The math of folding
If you would just do a simple fold over the middle, you will be doubling the number of layers. More often though, you will fold in a book fold (=no. of layers x 4) or a triple fold (bit like you would fold a letter for an envelope, often called letter fold as well). If you would do three book folds you will end up with: 1 x 4 x 4 x 4 = 64 layers already!
The importance of temperature
In order to make all those layers it is very important that the fat in between the dough layers remains solid. Once the fat starts melting it will sit within the dough and your layered effect can disappear. Therefore, you will find that a lot of recipes call for cooling your dough in between.
The importance of the right fat
Originally, the fat used for making puff pastry was butter. Mostly this was out of necessity, we didn’t have other solid fats that would behave in a similar way. Pork fat (lard) for instance is a lot softer than butter at room temperature and has a distinct (often not desired) flavour.
Nowadays, a lot of alternative fats are available though in the form of various margarines. Margarines are made of vegetable oils that have been hardened to behave more like butter. Because of this specific process manufacturers are able to control the properties of the margarine quite well, resulting in fats that are optimal for puff pastry making. For instance, they melt might less easily at room temperature.
Storing puff pastry
You can store freshly made puff pastry in the freezer for weeks’ on end. It is most important to ensure all those layers stay separate. Once you thaw the dough, it is ready for use.
Once puff pastry has been baked though it becomes harder to store. Puff pastry is best when it is crispy. however, as soon as it comes out of the oven it will start losing some of that crispiness. The moisture from the air will sit in the pastry layers, softening it over time.
Making puff pastry in a bakery
Puff pastry is made in a very similar way in a bakery as it would be at home. However, the bakers will have some convenient tools at their disposition. They can use a special rolling table for instance on which to roll out the dough with fat inside to prepare it for the next fold.
The video below is a great example of making puff pastry in a bakery. I would recommend playing it at twice the speed. Notice how flexible the dough is and how it looks smoother after rolling and folding several times. Also see how the baker takes care to fold it back into a nice rectangle every time. This way you don’t end up with parts that have less layers.
Making puff pastry in a factory
Now that you know the basic way how puff pastry is made, you will be able to recognize the process at larger scale as well, because it follows very much the same steps. You start by making a dough, you add a slab of butter, fold the dough closed and then fold it several times. You will notice that the techniques they use are slightly different since machines have to process the dough in a continuous manner. So, instead of using a single book fold for instance, the machine uses a continuous back and forth folding of dough ensuring that it can continue running.
How does 1x4x4x4 equal 56?
I get 64 layers
Counting layers has always been confusing
Thanks for spotting the error! You’re absolutely right, 4x4x4 does not equal 56 🙂
I hate to say it…
But this layer calculation is incorrect. Many websites and books use this straight multiplication system. It is not correct as you always have dough on the outside… unless you are making inverse pastry. For example if you make a book fold or a 4, the dough touched dough 3 times (-3) and in a letter fold or 3, the dough touches dough 2 times (-2). To make this real, take a small piece of dough, stretch it between your fingers, fold it over on its self and compress it…. there is only one thin layer of dough, not 2 as the dough merges. in the above example, I’m assuming that the 1 is a “3” lock-in and three book turns.
3 x 4 =12 (-3) =9 layers
9 x 4 =36 (-3) = 33 layers
33 x 4 = 132 (-3) =129 layers
The above calculation is a true representation of the layer numbers for a 3-4-4-4 lamination system.
In case you want to read more, Ive written a book on the subject called The Art of Lamination .
What is the name or vendor for the machine in the second video?
There are a lot of vendors that make this type of machinery. I believe the one on this video specifically is this one: https://www.rheon-europe.com/products/v4-pastry-lamination-line/ (it’s from the company Rheon). It’s called a pastry lamination line and I’m sure there are plenty of other companies out there making similar equipment, all with their own unique touches.