If I had to guess what type of flour the majority of people had in their cupboards, if any, it would be All-Purpose Flour. Makes sense, right, it’s for all purposes…? While this is true for the majority of baking needs, have you ever wondered why there are so many different types of flours?
Let’s start by defining the purpose of flour in a recipe. Flour provides protein which is essential to creating the structure of all baked goods, while also allowing them to rise in the oven. Different products require different amounts of protein, however, to achieve the desired texture. Pastries have little protein while pizza dough and pastas have a lot of protein. This explains why cakes are airy, soft, and even spongy, while breads have a firmer structure, by comparison.
All-purpose flour is a blend of high and low protein flours created to meet the needs of most home cooks. It contains a medium protein level.
|Flour Name||Type||Protein Content|
|Pastry||Soft red winter wheat||6.0-10.0%|
|All Purpose||Hard red winter wheat||10.0-11.5%|
Objective & Hypothesis
This experiment tests the effects of bread flour, pastry flour, and all-purpose flour on finished bread performance using a standard recipe.
A higher protein content means a stronger gluten network will develop, thus allowing the bread to have a firm, yet elastic structure. The low protein flour will produce a flat, dense product due to reduced formation of the gluten network and less air trapped.
5. Non-Fat Dry Milk
Three separate doughs were prepared using the same base formulas, substituting the test flours in each batch. Water content and mix time were also slightly adjusted to ensure optimal absorption and easier handling of each dough. This allowed each bread to perform at its best.
Is your dough fully mixed? Use the windowpane test to find out! Fully mixed dough should be smooth, matte, not lumpy, and maintain its shape around the dough hook after mixing.
Take a small piece of dough and slowly stretch it apart until it is very thin. If the dough breaks before you can stretch it, it is undermixed. If it stretches very quickly and tears easily, that means it has been overmixed. It should appear smooth and even.
A straight dough, no time process was used. This means all ingredients are mixed together at the same time at high speeds to reduce the time needed to prepare loaves.
Doughs were mixed for 11-13 minutes, rested for 20 minutes, rolled and folded, and proofed (allows the yeast to work and produce gas for the dough to rise) for 45 minutes.
Next up, time to bake. 24 minutes in a 425-degree oven.
Data and Results
Each dough was easy to work with and behaved very similar to the control (all-purpose flour). The bread flour and all-purpose flour doughs were not overly sticky, they had a matte shine, and they were strong, elastic and easily extensible.
The pastry flour dough was slightly stickier than the other two, due to less development of a gluten network that would absorb water. It was also weaker and did not have much spring back when rolling and molding.
Each loaf was very similar in color and tasted great! The crumb (fluffy part) was creamy-yellow and the crust a beautiful golden-brown. Right off the bat, I noticed a large difference in the volume of the bread flour sample. As predicted, it has a higher volume than the other two samples.
- Soft texture
- Semi-uniform air pockets
- Dense near the bottom crust
- Soft, but not exactly fluffy
- Largest rise
- Even crumb/air cells throughout
- Texture was soft and fluffy
- My favorite!
- Uneven loaf
- Lighter crust color
- Mixture of large and small air pockets
- Texture was soft, but slightly chewy
To give you a better idea of what’s going on in the crumb, take a look at this close-up. You can easily how much fluffier the bread flour sample looks compared to the other two. The pastry flour has a very condensed structure. All-purpose flour fell somewhere in the middle and would make an acceptable bread.
So, that brings us to the final question. “Can I substitute different types of flour for any recipe?” The answer: it depends! Keep in mind the protein content in the flour may cause negative effects when baking different types of products.
In general, use pastry flour for cakes and cookies, and bread flour only for bread products. For the average home baker, stick with all-purpose flour and it should work just fine.
*This post was adapted and modified from a report originally submitted as a class assignment