The characteristic of coarse wholemeal rye bread or coarse rye bread is significantly influenced by the granulation of the coarse grain. A wholemeal rye bread made exclusively from finely ground coarse wholemeal rye causes the sourdough to swell and acidify more quickly. This is due to the larger surface area of the coarse grain particles and the associated better wetting with water and better accessibility by enzymes. Higher acidity levels and also higher baked goods volumes are achieved.
If, however, coarsely ground coarse wholemeal grain is used, the swelling and acidification process is slower. The acidity levels are lower and the baked goods volumes are smaller.
The following series of baking comparisons was carried out to show how the dough and baked goods properties of wholemeal rye flour, finely ground coarse wholemeal rye, medium-ground coarse wholemeal rye and coarsely ground coarse wholemeal rye differ.
pH values, acidity levels and volume yield of coarse rye bread depending on the milled grain product used
When using only coarsely ground and medium-ground coarse wholemeal rye, the pH values and acidity levels of sourdoughs and bread show that insufficient swelling and acid formation has occurred. There was not enough metabolisable starch available for the lactic acid bacteria. In practice, sourdoughs for wholemeal rye bread are usually made from wholemeal rye flour or finely ground wholemeal rye and, in the recipe, medium-ground and coarsely ground qualities are usually added via hot soaked grain. The sole use of coarsely ground wholemeal rye is not recommended without additional pre-swelling in the form of soaked grain, hot soaked grain or boiled grain.
