Effects of diffusion controlled release of tocopherol on lipid oxidation

Our previous study showed that constant rate release of antioxidant was more effective than instant addition of antioxidant to inhibit oxidation of linoleic acid. However, the release rate of antioxidant from a packaging film is not constant-instead it varies with time, typically governed by diffusion of antioxidant in the film. This work investigated the effects of diffusion controlled release of tocopherol on inhibiting oxidation of linoleic acid. The results show that diffusion controlled release is more effective than constant rate release and instant addition, probably because the rate of diffusion controlled release of tocopherol more closely matches the rate of formulation of free radicals by linoleic acid. This finding provides useful insights for the design of controlled release packaging, an emerging technology by which antioxidants or other active compounds are released from the package in a controlled manner to extend shelf life of food.