Wheat flour's protein content determines how much gluten develops during mixing, which in turn affects dough strength and the finished product's texture — making it one of the most important specifications for bakery and industrial buyers.
Bakery-grade flour, used for bread and yeasted products, typically needs higher protein content to develop the gluten structure that traps gas during proving and gives bread its rise and chew.
All-purpose flour sits in a mid-range protein band suited to a wider variety of general baking applications, from cakes to flatbreads.
Industrial-grade flour specifications vary more by end use (noodles, biscuits, extruded snacks), so it's worth confirming the protein percentage range required for your specific product rather than relying on a general category name alone.
Related to: wheat flour