The objective of the research study was to determine the effect of probiotic bacteria strains on a free amino acid profile and sensory indicators of raw ripening sirloins. The research material consisted of raw ripening pork sirloins with probiotic strains (Lb. casei ŁOCK 0900, Lb. acidophilus Bauer, Bifidobacterium bifidum); the material was assessed immediately after ripening and after 2- and 4-month cold storage. Four experimental sample variants were prepared: control sample without any probiotic strain, sample with Lb. casei ŁOCK 0900 strain, sample with Lb. acidophilus Bauer strain, and sample with Bifidobacterium bifidum strain. The analyses comprised the determination of the level of peptides and of the profile of free amino acids, and the sensory assessment. It was found that the addition of probiotic bacteria affected sensory quality indicators of the product. The control sample was characterized by a lower sensory quality during the entire storage period compared to the samples with probiotics. Immediately after ripening, the sirloin sample with Bifidobacterium bifidum strain (9 j.u.) was rated as the best, and after 2- and 4- month storage, the sirloin sample with Lb. acidophilus Bauer strains (9.2 and 8.94 j.u., respectively). During cold storage, the best rated was the “taste of dried meat” indicator of the sample with a Lb. acidophilus Bauer (3.97 j.u. strain after ripening and 4.11 j.u. after 2 months, and 4.61 j.u. after 4 months); also, that sample was characterized by a high content of glutamic acid (0.49 mg/g, 1.15 mg/g, and 1.39 mg/g, respectively). Furthermore, a statistically significant increase, from 19.24 mg/g to 28.74 mg/g, was found in the content of free amino acid in the control sample after 4-month refrigerated storage. The sample with Lb. acidophilus Bauer strain contained more peptides: after ripening: 3.99 mg/g, after 2 months: 3.95 mg/g, and after 4 months: 3.43 mg/g compared to the control sample (after ripening: 3.53 mg/g, after 2 months: 3.9 mg/g, and after 4 months of storage 3.36 mg/g, respectively).