Ground beef or chicken breast muscle samples — either pretreated (PT) with 60 ppm chlortetracycline/0.2% potassium sorbate (to control microbial growth) or not pretreated (NPT) — were mixed with 0–5% NaCl and aerobically refrigerated for 0–6 days. NaCl increased 2-thiobarbituric acid-reactive substances (TBARS) values of stored beef and chicken, regardless of pretreatment, with its concentration having a quadratic effect on TBARS. After 3 or 6 days, beef samples were much higher in TBARS content than chicken samples. At each NaCl level, TBARS content increased or tended to increase with storage time for beef (NPT and PT) and PT chicken, but not in NPT chicken. Nonheme iron content in stored NPT and PT beef and PT chicken tended to increase with NaCl concentration.