The aim of this study was to evaluate the antioxidant effect of garlic and onion powder in beef and chicken patties during frozen storage for 120 days. Three different groups were produced for each type of meat (beef and chicken): beef and chicken patties without garlic and onion powder (control groups) (BC and CC), beef and chicken patties with garlic powder added at 0.70% (BG and CG), beef and chicken patties with onion powder added at 0.70% (BO and CO). The samples were analysed for pH, lipid and protein oxidation, colour and sensory properties. With the exception of the samples containing onion powder, the TBARS numbers of BC, CC, BG and CG increased during frozen storage and the highest TBARS numbers were determined on days 60, 90 and 120 (P < 0.05). The total protein carbonyl content of CG and CO did not change with the progression of frozen storage (P > 0.05). The addition of garlic powder preserved the a* value of beef patties during storage. The onion powder significantly improved oxidative stability by reducing TBARS number and total carbonyl content of beef and chicken patties (P < 0.05), while garlic powder had no significant effect on lipid and protein oxidation (P > 0.05). The beef patties with onion powder had a higher flavour score than the samples with garlic powder (P < 0.05). The garlic powder reduced the flavour and overall acceptance score of the chicken patties compared to the control group of chicken patties (P < 0.05). These results suggest that onion powder was an effective natural additive in terms of oxidative stability of beef and chicken patties and improved sensory properties.