Phenotypic characterization of lactic acid bacteria from sourdoughs for Altamura bread produced in Apulia (Southern Italy)

In order to study the composition of the lactic acid bacteria (LAB) community of sourdoughs used for the manufacture of Altamura bread, a traditional durum wheat bread produced in Apulia (Southern Italy), 111 strains of LAB were isolated and characterized. The phenotypic characterization of the isolates, carried out using a set of 29 tests, allowed the identification of 15 clusters at the 80% similarity level by hierarchical cluster analysis. Of the isolates, 88% were identified as facultatively heterofermentative LAB (Lactobacillus plantarum, Lb. paracasei, Lb. casei) and 12% as heterofermentative LAB (Lb. brevis, Leuconostoc mesenteroides). SDS-PAGE profiles of whole cell proteins of 68 strains confirmed the identification. Both the diversity and structure of the lactic microflora for sourdoughs for Altamura bread varied among samples.