In both types of pastry, the dough rises in layers or flakes. In Flaky Pastry the dough contains all the flour and water but only a low proportion of fat In Rough Puff all the fat is added to the flour in small pieces, but is not rubbed-in. The water therefore comes in contact with the flour in both these pastries so that the gluten develops into long strands resulting in layers of pastry.
The Flaky Pastry dough is thoroughly kneaded to strengthen the gluten in the flour and distribute the water evenly. (Never knead Rough Puff Pastry as all the fat is in the dough). For both pastries, by the method of rolling and folding, layers of dough are covered by layers of fat. Plain flour must be used and preferably a strong bread flour, for these pastries. Raising agents in self-raising flour will break up the long strands of gluten in the flour, which are necessary to produce a flaky result
Lemon juice is added to these pastries as it makes the gluten in the flour more elastic. This elasticity is necessary as the gluten has to stretch a great deal in order to rise and form the structure of the flaky layers. Resting in the refrigerator or cold place for a short time is essential to harden the softened fat and relax the stretched gluten and so be ready for re-stretching when required. Covering with a damp cloth or polythene bag prevents a skin forming on the outside of the dough. The rolling and folding is needed so that the pastry is even with no patches of margarine on the surface and to form the many flaky layers. Take care not to over-roll and mix the margarine with the dough, as this will prevent the layers forming.
The richer the pastry the hotter the oven that is required for baking. Flaky and Rough Puff need a hot oven (220°C, 425°F, Gas No. 7) or for some recipes a very hot oven (230°C, 450°F, Gas No. 8). A high temperature is needed to produce steam from the liquid and this steam forces the layers to rise. The high temperature is also needed to burst the starch grains quickly so that the large proportion of fat can be absorbed before the pastry sets. If the oven is too cool the margarine will run out and destroy the flaky layers.
Flaky and Rough Puff Pastry
1. Pre-heat the oven so that the correct temperature is reached before cooking the pastry.
2. Use Stork which is cool and firm (but not too hard) so that the pastry is easy to roll out. By being firm, the Stork will not melt until placed in the hot oven.
3. Use iced water in hot weather, otherwise very cold water. This will help to keep the fat firm and the dough from becoming too sticky.
4. Although a quantity of flour is needed for the various rollings, the surplus should be brushed off at each stage. If incorporated, lumpy, less rich pastry will result.
5. Flaky: knead the initial dough thoroughly so that the water is evenly distributed and the gluten developed.
6. Rough Puff: cut the pieces of Stork to the size of a walnut. If too large, they will be forced through the dough when rolling out. If too small they will mix with the flour to form a dough similar to Shortcrust and the results will not be satisfactory. Keep the pieces of Stork whole while mixing. When rolled out, they form the firm flat layers of fat between the layers of dough. It is important to handle this dough as little as possible. Do not knead.
7. When rolling and folding both pastries, keep the dough a good even shape and thickness, seal open ends carefully, using the rolling pin to keep in margarine and air.
8. Never turn pastry over during rolling. By turning it round gradually on the work surface before each rolling, the fat and water are evenly distributed through the dough. Always turn pastry round in the same direction.
9. Resting in a refrigerator or cold place allows the fat to become firm and pastry to relax.
10. Instead of greasing the baking sheet, sprinkle with a little water, which is converted to steam in the hot oven. The steam helps the pastry to rise.