The results showed the high GABA-producing ability of the L. brevis strains, CECT 8183, CECT 8181, CECT 8182 and L. lactis ssp lactis CECT 8184, under nonoptimized conditions, opening new ways of research to optimize the production of GABA and the possibility of creating co-cultures with these strains. Furthermore, the findings of this study make it possible to use these strains in the bakery industry to obtain healthpromoting bakery foods that are rich in GABA.