Identification of Lactic Acid Bacteria Isolated from Sourdoughs Produced with Flours of Different Cereals in North-Western Spain via MALDI-TOF MS and pheS Gene Analyses

Lactic acid bacteria (LAB) are Gram-positive cocci or rods from different genera and species that synergistically coexist with yeasts in cereal sourdoughs. Although the production and consumption of sourdough breads have increased in the last decade, there are still few studies that identify the LABs present in sourdoughs of different origins. In this study, we identified LAB strains isolated from wheat sourdoughs sourced from bakeries in north-western Spain and from experimental sourdoughs developed by a baker with four different cereal flours: wheat, rye, spelt, and tritordeum. Through a combination of MALDI-TOF and pheS gene sequence analyses, we identified Lactiplantibacillus plantarum and Levilactobacillus brevis in all analysed sourdoughs. Moreover, Lactiplantibacillus paraplantarum, Lacticaseibacillus paracasei, Lactococcus lactis, Pediococcus pentosaceus, and Weissella paramesenteroides were identified in different sourdoughs. These species were also isolated from sourdoughs obtained in other European countries, although we did not identify the other LAB genera identified in some of them. Our results demonstrate the need to identify the LAB species from sourdoughs of different origins prior to designing suitable starters for inoculated sourdoughs, particularly those produced with innovative flours. To our knowledge, this is the first report on the identity of LABs present in tritordeum sourdoughs in Spain.