73D-5 |
Characteristics of antimicrobial edible films from cellulose-based materials incorporated with propolis extracts |
C. T. KIM1, S. J. Lee2, Y. J. Cho, C. J. Kim, W. S. Shin, and A. J. Choi. (1) Food Process Engineering Team, Korea Food Research Institute, San 46-1, Baekhyundong, Bundangku, Songnam, 463-420, South Korea, (2) Dept. of Food & Nutrition, Bucheon College, Simgokdong 424, Wonmigu, Bucheon, Kyonggido, 463-420, South Korea Edible films have been developed in order to improve the food quality and to extend the shelf life, due to its regulating function of water transferring in food products. Edible films can be based on polysaccharides, proteins, lipids, or their combinations. Recently, active packaging concepts have been introduced. Active packaging is an innovative concepts including O2 and ethylene scavenging, CO2-scavengers and -emitters, moisture regulators, antimicrobial packaging, antioxidant release, release or adsorption of flavours and odours. The antimicrobial edible film is one of the most promising applications of active packaging where the antimicrobial substances is released from the films onto the food surface and inhibits the microbial growth. To control the microbial activity on foods, antimicrobial substances can be incorporated in or coated onto food packaging materials. Ethanol extracted propolis has been selected as the antimicrobial agent due to its strong antifungal and antibacterial activity . The objective of this research was to examine the inhibition effect of microbial growth by the edible films incorporated with propolis extract. The mechanical properties, water vapor permeability, microstructure and optical property were examined under a variety of relative humidity conditions. Cellulose-based edible films were incorporarted with different concentration of propolis in order to find out the overall range of antimicrobial activity. The water vapor permeabilities (WVP) of the films were evaluated at 25°ĘC using the WVP Correction Method. UV/VIS/NIR spectrophotometer was used to determine the microstructure and the optical property of edible films. Antimicrobial activities of the resulting edible films against several microorganisms including Lactobacillus plantarum, Escherichia coli, Saccharomyces cerevisiae, and Fusarium oxysporum were determined. Relative humidity increases and propolis content decreases results in increased WVP values for all edible film products. The diffusion rate and final equilibrium amount of total flavonoids increased as the propolis concentration increased. As a safe method, without a chemical coupling reaction process, the incorporation technique of propolis could use a good antimicrobial materials.
Session 73D, Food Packaging
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