Sponge
You need a flour that does not add strength: excess gluten makes a sponge dense and rubbery. Premium grade with even figures is optimal. What matters here is not the absolute number but consistency from batch to batch — a sponge recipe is sensitive.
Shortcrust
The task is the opposite — minimal gluten development. Premium and Extra both work with a short mix at low temperature. A high-ash flour gives a greyish tint that shows in confectionery.
Puff pastry
The one confectionery item that needs strength: gluten from 30% so the layers hold through rolling and rise. Here Extra fully earns its place.
What most often ruins the result
- Changing batch in the middle of a production run of made-to-order cakes.
- Storing flour next to aromatic products: confectionery picks up foreign smells more sharply than bread.
- Trying to cover both sponge and puff pastry with a single flour.
The practical answer is two grades in rotation and a batch reserved for your production.