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The aim of this study is the isolation, characterization and identification of autochthonous lactic acid bacteria (LAB) from artisanal Vlasina raw goat's milk cheese for the selection of potential starter cultures. Soft white Vlasina cheese was manufactured at a household on the Stara Planina Mountain using traditional techniques without starter cultures. One hundred and forty nine LAB isolates were collected from two samples of Vlasina cheese, designated as BGVL2 (5 days old) and BGVL2a (15 days old). The population of LAB in the cheese samples was characterized by phenotype-based assays and presumptively identified using repetitive element palindromic polymerase chain reaction (rep-PCR) with the primer (GTG)5. Results were confirmed by 16S rDNA sequencing. Among the BGVL2 isolates (56), the most numerous LAB species were Leuconostoc pseudomesenteroides (27) and Lactococcus lactis (26). In 15-day-old BGVL2a (93 isolates), Lactobacillus plantarum (33), Enterococcus durans (26) and Pediococcus pentosaceus (14) were predominant. Lc. lactis ssp. lactis BGVL2-8 showed good acidification ability and the ability to produce antimicrobial compounds, Lb. plantarum BGVL2a-18 had good proteolytic ability and produced exopolysaccharides, while BGVL2-29 and BGVL2-63, which belonged to the species Ln. pseudomesenteroides, utilized citrate and produced diacetyl and acetoin. They appeared to be suitable candidates for inclusion in the starter culture. This study contributed to the understanding of the role of autochthonous LAB in the quality of artisanal cheese and the possibility of using the selected LAB as potential starter cultures for cheese making under controlled conditions., Svrha je ovoga rada bila izolirati, karakterizirati i identificirati autohtone bakterije mliječno-kiselog vrenja koje se mogu upotrijebiti kao starter kulture u zanatskoj proizvodnji vlasinskog sira iz svježeg kozjeg mlijeka. Meki je bijeli vlasinski sir bio izrađen u domaćinstvu na Staroj Planini tradicionalnim postupkom bez dodatka starter kultura. Iz dvaju je uzoraka vlasinskih sireva, označenih kao BGVL2 (sir star 5 dana) i BGVL2 (sir star 15 dana) prikupljeno 149 izolata bakterija mliječno-kiselog vrenja. Populacija je bakterija iz uzoraka sireva okarakerizirana pomoću fenotipskih testova i primarno identificirana primjenom metode rep-PCR s početnicom (GTG)5. Rezultati su potvrđeni sekvenciranjem 16S rDNA. Među izolatima iz sira BGVL2 (njih 56) najbrojnije su bile bakterije Leuconostoc pseudomesenteroides (27) i Lactococcus lactis (26). U siru BGVL2a (93 izolata), starom 15 dana, prevladavale su vrste Lactobacillus plantarum (33), Enterococcus durans (26) i Pediococcus pentosaceus (14). Izolat Lc. lactis ssp. lactis BGVL2-8 pokazao je dobru sposobnost zakiseljavanja i proizvodnje antimikrobnih spojeva. Izolat Lb. plantarum BGVL2a-18 imao je dobru proteolitičku aktivnost i sposobnost proizvodnje egzopolisaharida, dok su izolati BGVL2-29 i BGVL2-63 vrste Ln. pseudomesenteroides za rast koristili citrate, a proizvodili diacetil i acetoin. Stoga su navedeni izolati odabrani kao starter kulture. Ovo je istraživanje pridonijelo razumijevanju uloge autohtonih bakterija mliječno-kiselog vrenja u zanatskoj proizvodnji kvalitetnog sira, te je potvrdilo mogućnost primjene odabranih izolata kao starter kultura pri izradi vlasinskog sira u kontroliranim uvjetima.