Astaxanthin from Shrimp By-Products Enhances Oxidative Stability of Lard During Storage

Previous research has primarily focused on the antioxidant effect of astaxanthin (AX) in various vegetable oils, with limited attention given to its behavior in lard. This study aimed to evaluate the degradation of AX during lard storage and to assess the physicochemical changes occurring in lard containing different AX concentrations over time. The variation in AX concentration was monitored using spectrophotometric analysis. To characterize the changes in lard, both thermal and chemical methods were employed: thermal analysis was used to determine the onset oxidation temperature (To) and activation energy (Ea), while chemical methods included peroxide value (PV) and thiobarbituric acid reactive substance (TBA) assays. Optimization of AX concentration and temporal evaluation of its antioxidant effect were performed using Response Surface Methodology (RSM). The results indicated a significant degradation of AX after 30 days of storage. An AX concentration of approximately 3 mg/g was identified as optimal, as it provided the highest thermal stability and the lowest levels of oxidation markers, offering a well-balanced compromise between technological performance and preservative effectiveness in lard during storage. Additionally, the color of the lard was found to be more strongly influenced by the presence of AX itself rather than by its specific concentration.