Flour Types Explained
What actually separates these flours is protein content — and protein content is what decides gluten, structure, and texture.
| Flour | Protein | Best for |
|---|---|---|
| Cake flour | ~7–9% | Tender, fine-crumbed cakes; low gluten for a soft bite |
| Pastry flour | ~8–10% | Pie crust, biscuits, some cookies; flaky, tender texture |
| All-purpose (AP) | ~10–12% | General baking; a workable middle ground for most recipes |
| Bread flour | ~12–14% | Yeasted breads; strong gluten for chew and structure |
| 00 flour | ~11–12.5% (varies by type) | Pizza dough, fresh pasta; very finely milled |
| Whole wheat | ~13–14% | Denser, more flavorful breads; includes bran and germ |
| Self-rising | ~8–9% (AP + leavening/salt) | Biscuits, quick breads where no separate leavening is added |
Protein percentages vary by brand and region — these are typical ranges, not a fixed spec.
Protein content is what becomes gluten
When flour is mixed with water and worked (kneaded, whisked, folded), its proteins form gluten — the stretchy network that gives bread its chew and structure. More protein means more gluten potential, which is exactly why bread flour (high protein) makes a chewy, structured loaf, while cake flour (low protein) makes a soft, tender crumb that would collapse if asked to hold up a loaf of bread.
Using the "wrong" flour doesn't ruin a recipe, it changes it
Substituting all-purpose for bread flour in a yeasted bread recipe generally still works, just with a slightly softer, less chewy result since there's less gluten-forming protein available — substituting bread flour for cake flour in a delicate cake is more noticeable, often producing a tougher, denser crumb than intended, since the extra gluten fights against the tenderness the recipe is going for.
00 flour is about milling fineness, not just protein
The "00" designation (an Italian milling classification) refers to how finely the flour is ground, not directly to protein content — that fine grind is what gives pizza dough and fresh pasta their particular smooth, extensible texture, on top of whatever protein level that specific 00 flour happens to have. Some 00 flours are milled specifically for pizza (moderate protein) and others for pasta (can be higher or lower depending on the blend).
Self-rising flour is a shortcut, not a different base flour
Self-rising flour is just all-purpose flour with baking powder and salt already mixed in at a standard ratio — convenient for recipes designed around it (many Southern biscuit recipes), but it's not a substitute for plain all-purpose in a recipe that adds its own leavening separately, since you'd end up with leavening added twice.