The effect of oxidation in the lipid structure on the content and lipid quality depending on the storage conditions of the dog and cat food

This study was conducted to evaluate the oxidation processes occurring in 10 different cat and dog foods stored under household conditions with their packaging left open for 42 days. Weekly analysis of Peroxide Value, Rancimat Induction Time, moisture content, ambient temperature, and humidity were performed on local and foreign brand foods which contains synthetic antioxidants. Fatty acid composition analyses were carried out at the beginning and end of the study, and correlations among oxidation indicators were assessed within 95% and 99% confidence intervals. Although oxidation in pet foods is known to begin during the manufacturing process, this study clarify how oxidation progresses in foods stored with open packaging under household conditions and examined the relationships between oxidation and fatty acids compositional factors. Changes in fatty acid composition and the effects of fatty acid fractions on oxidation processes were specifically evaluated. The selection of mid-price segment products allowed observation of the impacts of synthetic antioxidants and different lipid sources (animal-based and plant-based) on oxidative processes. Results showed that cat foods had higher average Rancimat Induction Times compared to dog foods, suggesting that the selected cat foods may exhibit greater oxidative stability. Ambient conditions were found to influence Rancimat Induction Times, with this effect being more pronounced in dog foods. The combined evaluation of Peroxide Value and Rancimat Induction Time alongside fatty acid composition provided a comprehensive assessment of oxidation processes. Peroxide Value was found to correlate with saturated fatty acid content, while ambient humidity played a limited but statistically significant role in these changes. The study was based on the premise that oxidation processes in pet foods are affected within a 42-day period by owners' observed usage behaviors, potentially impacting palatability. To simulate this, subjective usage criteria such as storage location, frequency of use, and packaging opening methods were replicated. Findings indicated that the relationship between total fat content and fatty acid profile in formulations is a key determinant of oxidative stability. Foods with lower Peroxide Values are known to be consumed more eager, highlighting the importance of considering fat content and environmental conditions when determining formulation and lipid sources. The study concluded that Rancimat Induction Time can be a preferred method for accelerated stability testing of pet foods. It is recommended that antioxidant contents should be declared on product labels, manufacturers choose lipid sources with consideration of oxidative stability, and packaging include information on appropriate storage conditions to ensure both product quality and animal health. Additionally, manufacturers are advised to provide supplementary information on ideal storage and preservation conditions on packaging and promotional materials, and to educate retailers and pet owners accordingly.