According to the Leitsätze für Brot und Kleingebäck (guidelines for bread and morning goods), up to 20 % of bread (calculated as fresh bread) may be used. The bread must be in a hygienically impeccable and marketable condition. Furthermore, it must not have been accessible to direct contact by the customer prior to processing. The added fresh bread must not be perceptible later to the naked eye in the baked goods made with it. [Cf: Leitsätze für Brot und Kleingebäck (Guidelines for bread and morning goods), new version of 01.04.2021 (BAnz AT 06.05.2021 B2, GMBl 29/2021 p. 654-659)]
If, for example, coarse wholemeal rye bread is produced, the fresh bread added to the recipe must be coarse wholemeal rye bread, as well.
The fresh bread is usually soaked with water at a ratio of 1:2 before it is added, so that it is evenly distributed and dissolved in the dough during dough preparation.
If the fresh bread is dried before processing, only an amount of dried bread equivalent to the same quantity of undried fresh bread may be added.
The dried and sometimes toasted bread is pre-swollen with water in a ratio of 1:2 or 1:3 and is not added in dry form. The use of hot water is recommended for swelling bread and for achieving the desired dough temperature. Adding too much bread (more than 15 % of fresh bread) can lead to crumb aeration and/or crumb instability.