BACKGROUND: This study investigated the effects of various ripening conditions and starter culture additions on the microbial composition and physicochemical properties of Turkish fermented sucuk. Ripening conditions (spontaneous, controlled, and controlled with starter culture) were evaluated using metagenomic technology. Key physicochemical properties, including moisture, pH, water activity, titratable acidity, residual nitrate, residual nitrite, and color properties, were analyzed. RESULTS: Three groups were produced: group A (spontaneous conditions); group B (controlled conditions); and group C (controlled conditions with starter culture). Microbial and physicochemical properties were assessed at three key time points: beginning (t1 – sucuk dough), middle (t2), and end (t3) of the ripening process. Physicochemical analyses showed a decrease in moisture content (from 53–54% to 39%), an increase in acidity (from 0.59% to 1%), and a reduction in nitrate levels (especially in sucuk produced with starter cultures under controlled conditions from 65.22% to 5.97%) throughout the ripening period (P < 0.05). Microbial analyses revealed that Latilactobacillus sakei dominated the bacterial composition (57.9%) in group B, while the lowest bacterial diversity was observed in group C, and the highest diversity was in group A. The most detected fungal genus in the sucuk samples was Pichia, followed by Hanseniospora, Alternaria, Kluyveromyces, Cladosporium, and Monascus. CONCLUSION: The ripening conditions and starter culture application significantly influenced both microbial and physicochemical characteristics of fermented sucuk. Controlled fermentation, particularly with starter cultures, resulted in reduced microbial diversity but enhanced the dominance of beneficial microorganisms. These findings contribute to optimizing sucuk production for improved safety and consistent quality. © 2025 Society of Chemical Industry.