Mortadellas were reformulated by replacing animal fat with hydrolyzed collagen (HC) at 50 % and 70 % levels, substituting 50 % NaCl with KCl, and adding 1 % arginine. The effects of these changes on physicochemical properties, sensory attributes, and shelf life over 60 days at 4 °C were evaluated. The results showed that substituting 50 % and 70 % of fat with HC reduced fat content by 42.6 % and 55.3 %, respectively, while increasing protein levels by 37 % and 55 %. Replacing 50 % of NaCl with KCl reduced sodium content by 33.2 % and increased potassium content by 234.7 %. The 50 % HC substitution was the most suitable, as it preserved sensory attributes and structural integrity, unlike the 70 % replacement, which negatively affected texture and taste. Although substituting NaCl with KCl introduced sensory defects like bitter and metallic tastes, adding arginine effectively masked these issues, resulting in sensory quality comparable to the control. Oxidative stability, evaluated through TBARS values and sensory assessments, was similarly maintained across all treatments throughout storage. Counts of aerobic mesophilic microorganisms and lactic acid bacteria evolved similarly in reformulated products and the control, ensuring microbiological stability. The pH levels remained consistent across treatments, and color stability, assessed by ΔE values, was preserved throughout storage. These results highlight the feasibility of reformulating mortadellas with HC, KCl, and arginine to produce healthier products without compromising sensory quality, physicochemical stability, or shelf life.