Authors Ayranci, E. & Tunc, S.,
A method involving the flow of O2 and N2 gasses from the two sides of an edible film coupled with a simple wet chemical analysis at the end was developed to measure the oxygen permeability of edible films. The proposed method was employed to determine the oxygen permeability of methylcellulose (MC)-based edible films of various compositions with the aim of finding the optimum composition for minimizing oxidative degradation of foods. The effects of the presence of stearic acid (SA), ascorbic acid (AA), and citric acid (CA), in varying amounts in the film composition, on the oxygen permeability (OP) of MC-based edible films were examined. The OP increased with increasing SA content of the film and decreased with the inclusion of AA or CA in the film composition. The films, with various compositions and with the measured oxygen permeabilities, were then applied to mushrooms (Agaricus bisporus) and cauliflower (Brassica botrytis). It was found, from the analysis of these coated foods, that the coatings containing antioxidants slowed the browning reactions and reduced the vitamin C loss in both foods, the effects being greater in cauliflower. Moreover, the moisture loss of coated foods was less than that of uncoated. respiration rate; permeation; film properties; postharvest, and shelf life of fresh, or minimally processed fruits and vegetables, using edible film, have been performed in recent years. This film has been applied to fruits, such as oranges, tomatoes, and grapes, with satisfactory results. However, the results are not always favorable, and can affect fruit quality, due to the modification of their internal atmosphere. this, in turn, causes alterations to the respiration and internal composition of the gases within the product, most recent investigations have focused primarily on the development of new films and the study of the properties (e.g. firmness, color, product weight loss) acquired by the food after film application, however, further studies are required to investigate both barrier properties and gas permeability, as well as to unify the procedures involved in the measurement of these parameters, Edible films should meet specific requirements that depend on the type of product to be coated and the metabolic routes involved. These properties include adequate water vapor and solute permeabilities, selective permeability to gas and volatile compounds, uniform thickness, and is free of wrinkles, creases, pinholes, and other imperfections, Edible films are generally formed from polysaccharides, proteins, lipids, or a combination of these compounds. Material barrier properties, concerning water vapor, oxygen, carbon dioxide, and the transfer of lipids, in specific food systems, depending on the compounds used, coating material selection is generally based on water solubility, hydrophobicity, ease of film formation, and sensory properties, Edible film permeability, Gas transmission rate, Water vapor transmission rate, Permeation and permeability, Gravimetric and static methods, water vapor transmission rate, Oxygen and carbon dioxide transmission rates, Methods of pressure measurement, Continuous-flow or isostatic method, Electrochemical methods (i.e. coulometry), Chemical methods (i.e. iodimetry), Methods and test conditions for gas permeability measurement in edible films.
