Article pubs.acs.org/JAFC
Active Food Packaging Based on Molecularly Imprinted Polymers: Study of the Release Kinetics of Ferulic Acid Pablo Otero-Pazos,† Ana Rodríguez-Bernaldo de Quirós,*,† Raquel Sendón,† Elena Benito-Peña,§ Victoria González-Vallejo,§ M. Cruz Moreno-Bondi,§ Immaculada Angulo,# and Perfecto Paseiro-Losada† †
Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Pharmacy, University of Santiago de Compostela, Campus Vida s/n, 15782 Santiago de Compostela (La Coruña), Spain § Department of Analytical Chemistry, University Complutense de Madrid, 28040 Madrid, Spain # GAIKER Technological Center, 48170 Zamudio, Spain ABSTRACT: A novel active packaging based on molecularly imprinted polymer (MIP) was developed for the controlled release of ferulic acid. The release kinetics of ferulic acid from the active system to food simulants (10, 20, and 50% ethanol (v/v), 3% acetic acid (w/v), and vegetable oil), substitutes (95% ethanol (v/v) and isooctane), and real food samples at different temperatures were studied. The key parameters of the diffusion process were calculated by using a mathematical modeling based on Fick’s second law. The ferulic acid release was affected by the temperature as well as the percentage of ethanol of the simulant. The fastest release occurred in 95% ethanol (v/v) at 20 °C. The diffusion coefficients (D) obtained ranged between 1.8 × 10−11 and 4.2 × 10−9 cm2/s. A very good correlation between experimental and estimated data was obtained, and consequently the model could be used to predict the release of ferulic acid into food simulants and real food samples. KEYWORDS: molecularly imprinted polymers, ferulic acid, kinetic release, partition and diffusion coefficients
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INTRODUCTION Lipid oxidation is one of the main causes of food quality deterioration. This process involves the development of offflavors, making the product undesirable to consumers.1 Several approaches have been employed by the food industry to prevent or retard lipid oxidation and consequently extend the shelf life of the food products. Among them, active food packaging has been demonstrated to be effective in controlling oxidative degradation.2−5 Active food packaging is designed to interact actively with the product or with its environment to maintain or improve the food quality and safety and increase the shelf life of the packed foods.6−8 Particular attention has been given to controlled release active packaging. These systems provide a sustained delivery of the active substance; therefore, a critical concentration in the packed food is maintained for a certain period of time.9−13 Different examples of technologies to develop controlled release systems for food packaging applications have been reported in the literature. Microencapsulation is one of the most commonly used. Flavoring agents, additives, enzymes, lipids, or vitamins have been microencapsulated using different materials depending on subsequent application.14 Frascareli et al.15 described a spray-drying microencapsulation process using Arabic gum for the encapsulation of coffee oil. Koontz et al.16 investigated the cyclodextrin complexes of α-tocopherol and quercetin as a controlled release system of natural antioxidant for food-packaging applications. Wan et al.17 reported the microencapsulation of nisin by using calcium alginate as matrix material. The microparticles developed in this study presented a size
