The current study assessed the minimum inhibitory concentration (MIC) of Cowpea-legumin (CPL) against antibiotic-resistant foodborne pathogens (FBP), the consequences on Longissimus thoracis et lumborum (LTL) quality and shelf-life, and the growth curves of inoculated FBPs. Fresh LTL-steaks were enriched with either 0.5 mg/g (CPL0.5) or 1 mg/g (CPL1) and evaluated over 15 chilling-days at 4 °C. Antibiotic-resistant Salmonella enterica and Escherichia coli were inhibited by 25 and 3.125 mg/mL, respectively, while antibiotic-susceptible FBPs and antibiotic-resistant Staphylococcus aureus were suppressed by 0.1 mg/mL CPL. CPL1-fortification produced fully tender LTL that was initially yellower/less red than the control, then turned brighter red with storage. CPL demonstrated promising dose-dependent antioxidant, and antibacterial activities against native spoilage and antibiotic-resistant/susceptible FBPs. CPL’s proteinaceous composition, besides sample size, might impact stability. Conclusively, CPL demonstrated promising preservative stability in fresh meat for a maximum of fifteen-days and represents a viable antimicrobial alternative in battle against antibiotic-resistance.