Complex sentence: In the 19th century some bread bakers obtained their yeast from beer brewers, and this led to sweet-fermented breads such as the Imperial "Kaiser-Semmel" roll, which generally lacked the acid sourness typical of lactobacillus.
Split into simpler sentences: In the 19th century some bread bakers obtained their yeast from beer brewers. This led to sweet-fermented breads such as the Imperial "Kaiser-Semmel" roll, which generally lacked the acid sourness typical of lactobacillus.