Livet i en surdeg : Olika mjölksyrabakteriers inverkan på surdegsbröd

Sammanfattning: The key elements of sourdough fermentation are the presence of active lactic acid bacteria (LAB) and yeast. Sourdough fermentation originates from the ancient Egypt. One theory concerning its onset states that a portion of bread dough was set aside to be baked at a later date and started to ferment spontaneously.Sourdough may contain a wide variety of microorganisms, mainly dominated by LAB and yeast. There are over 50 species of LAB that has been identified in various sourdoughs and more than 20 species of yeast. Sourdough fermentation has been shown to have various impacts on baked cereal good, most of which are attributed to LAB.This study addresses some effects of LAB from fermented milk products in sourdough and sourdough bread. Three different kinds of fermented milk products, “yoghurt”, “A-fil” and “kefir-fil” have been used to start sourdoughs and ultimately bake sourdough breads. These sourdoughs and sourdough breads were monitored during their development and compared via laboratory exercises, observations and sensory analysis.The results show differences in bacterial growth as well as acidification and final volume of the bread loafs. Although the sensory analysis showed no difference between the samples, the collected results indicate that out of these three fermented milk products “kefir-fil” would be the most suitable as a sourdough starter.Keywords: sourdough bread, fermented milk products, lactic acid bacteria, bread quality, bacterial culture.