83B-15 |
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J.-W. PARK1, B.-H. Kim1, and W. S. Whiteside2. (1) Food and Bio Technology, and Food and Bioindustrial Research Center, Hankyong National University, 67 Seokjeong-dong, Ansung, Kyonggi-do, 456-749, South Korea, (2) Packaging Science, Clemson University, Clemson, SC 29634 Chitosan is the second largest biomass after cellulose on earth. Also, there are a lot of potential possibilities to use chitosan as a functional food package because of its antibacterial activity. Since the melting temperature of chitosan is too high likewise most other biopolymers, however, chitosan films have been made by casting method. Among other biopolymers, gelatin has a relatively low melting temperature depending upon the amount of plasticizer. Therefore, gelatin was used to make up for chitosan°¯s thermal weak point to produce commercially feasible film. The objective of the current study was to determine the optimum blend ratio and amount of chitosan-gelatin blend solutions against antibacterial activities for extruder resin. Gram-positive bacteria (Bacillus cereus ATCC 14579 and Listeria monocytogenes ATCC 15313) and gram-negative bacteria (Escherichia coli ATCCC 25922 and Salmonella enteritidis IFO 3313) were used. Paper (8 mm) diffusion method and optical density method were used to evaluate the effect of different blending ratio solutions on the inhibition of bacterial growth. The measured clear zone size ranged from 8 to 18.07 mm in paper diffusion test. For B. cereus, E. coli, and S. enteritidis, the clear zone was appeared when 50 mL of blend solution (chitosan : gelatin=2:8) was poured onto the paper. At this point, the added amount of chitosan was 0.3 mg. In L. monocytogenes case, the inhibition effect was occurred when the added amount of chitosan was 0.6 mg (chitosan : gelatin=4:6). The minimum inhibitory concentration (MIC) values of the added amount of chitosan for B. cereus, L. monocytogenes, E. coli, and S. enteritidis were showed at 0.1461, 0.3365, 0.1461 and 0.049 mg/mL, respectively. These results give us possibility to make commercially feasible film with optimum chitosan-gelatin amount.
Session 83B, Food Packaging: Applications of edible coatings, antimicrobial films, and sensors in food packaging
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