How does altering the fat-to-flour ratio affect the pastry?
Typical pastry recipes(pate sucre and pate brisee) follow the 2:1 ratio for flour and butter, other recipes (American pie crust, German shortcrust) can have a lower ratio (1.5, 1.29). How does the higher fat content affect the finished product?
Best Answer
Flour (+ water, either directly or from other ingredients such as egg white) gives the pastry structure. As you knead the flour, the gluten network develops and results in elasticity. When cooked, water evaporates from the dough leaving a rigid gluten skeleton.
Fat does not mix with water and thus stay in blobs in between the gluten network. This weakens the gluten structure, making the pastry crumble.
For this reason, you often see in recipes for shortcrust to avoid overmixing the fat. Buttery biscuits such as shortbread crumble more than crackers, which have more water. The same rationale applies to puff pastry. The thin fat layers are impermeable, so water steam gets trapped and exercise pressure upwards, lifting the pastry up.
Quoting @GdD in the comments, the punchline is:
more fat = crumblier, less fat has more structure.
Pictures about "How does altering the fat-to-flour ratio affect the pastry?"
What will happen if the fat is increased or decreased in short crust pastry?
Fat does not mix with water and thus stay in blobs in between the gluten network. This weakens the gluten structure, making the pastry crumble. For this reason, you often see in recipes for shortcrust to avoid overmixing the fat. Buttery biscuits such as shortbread crumble more than crackers, which have more water.What ratio of fat to flour makes the best pastry?
The most flaky, tender crust comes down to a simple 3:2:1 ratio of ingredients\u2014flour, fat, water\u2014 no actual recipe needed.What happens if too much fat is added to pastry?
My pastry is very crumbly This can happen if you use too much fat or over mix the pastry. The pastry may be too dry and may not contain enough liquid to properly bind the fat and flour.What function does fat have in pastry making?
The role of the fat in making a pastry is to give texture to the final product. Depending on the kind of fat used, the pastry will also have a certain flavor. Pastry chefs use various types of fats, like vegetable shortening, butter, or lard.How Different Fats Affect Bread Dough | The Effects of Fat Explained
Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.
Images: Gustavo Fring, Gustavo Fring, Gustavo Fring, Gustavo Fring