Formulation and characterisation of novel edible-packaging for fruits and vegetables

Abstract: This master's thesis investigated the potential of algae raw materials, specifically k-carrageenan and to a lesser extent alginate, as film-forming ingredients for the development of a novel edible packaging solutions. The project involved the testing and characterisation of several active ingredients of algal and plant origins both as extracts and as ingredients in films. The effect of these films on the shelf life of cucumbers was evaluated over the course of a 14-day shelf-life study where coated samples were compared to plastic film-wrapped and unwrapped controls, respectively. The project involved the development and characterisation of different coating formulations, and the subsequent evaluation of their effectiveness in prolonging shelf-life by through weight loss, scavenging activity (DPPH), colorimetry and relative electrolyte leakage (REL) measurements. A The results indicated that coatings did not significantly extend shelf-life in coated cucumbers when compared to uncoated and plastic-wrapped samples. The rate of weight loss of coated and uncoated cucumbers was similar, and plastic-wrapped samples lost significantly less weight (p<0.05). REL values were lower for uncoated and wrapped controls than for coated samples. Results from DPPH-assay and colorimetric measurements were inconclusive, and it is suggested that these experiments be repeated with some modifications. Overall, results provide important insights into the suitability of carrageenan-based coatings as edible coatings, with and without the addition of active ingredients. The results of this study demonstrated that further research on formulation and development of films is necessary to ensure satisfactory mechanical and barrier properties, and thereby quality retention in coated produce. Future outlooks include the continued evaluation of k-carrageenan formulations, different antioxidant sources and incorporation methods. Replicating the study (with modifications) with a secure access to instruments and resources may also provide further insights.