Why is soft plain flour used in pastry making?

1. Low Gluten Content: Soft plain flour has a lower protein content (gluten) compared to other types of flour. Gluten is what gives dough its elasticity and chewiness. In pastry, you want a tender, flaky texture, not a chewy one. Less gluten means the dough will be more delicate and less likely to become tough.

2. Fine Texture: Soft plain flour has a finer texture than other flours, resulting in a smoother pastry that will roll out more easily. This fine texture also contributes to the overall lightness and tenderness of the pastry.

3. Absorption of Fat: Soft plain flour absorbs fat more effectively than other types of flour. This is crucial in pastry making because the fat is what helps create the layers and flakiness. The flour readily absorbs the fat, allowing it to distribute evenly and form the desired structure.

4. Absence of Additives: Soft plain flour is usually unbleached and unbromated, meaning it doesn't contain any additives that could interfere with the gluten development or affect the final texture.

In summary: The low gluten content, fine texture, and ability to absorb fat make soft plain flour the ideal choice for creating light, flaky, and delicious pastries.