Assessing the efficacy of rosemary extract as a natural preservative for enhancing oxidative stability and preventing rancidity in linseed oil

Abstract

This study explored the efficacy of rosemary as a natural antioxidant and preservative to combat oxidative rancidity in linseed oil. The characterization of rosemary essential oil and extract demonstrated a high phenolic content, particularly in rosmarinic and carnosic acids. Utilizing optimized mixture design, a potent fat preservative was developed that leveraged the synergistic interactions of these rosemary compounds. The preservative exhibited significant antioxidant activity, evidenced by reductions in acidity levels (0.773 to 1.097) and peroxide values (1.473 to 2.494), as well as notable shifts in extinction values of linseed oil subjected to thermo-oxidative stress. Furthermore, it effectively preserved the stability of key fatty acids, outperforming the synthetic preservative BHT in preventing the oxidation of primary fatty acids, including stearic, oleic, linoleic, and α-linoleic acids. These findings underscored the potential of rosemary-derived preservatives to enhance oxidative stability and extend the shelf life of linseed oil, offering promising implications for food quality and safety.