• Korean Journal of Human Ecology
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• v.14 no.2
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• pp.321-330
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• 2005

The antimicrobial activity of PHB/chitosan films and the quality of white bread packaged with the films were investigated. Chitosan film showed the highest antimicrobial activity and PHB(L) film also showed high antimicrobial activity against Fusarium solani KCTC 6636 and Penicillium citreonigrum KCTC 6927. White bread packaged with chitosan film had good moisture retention. $L^*\;and\;b^*$ of white bread increased but $a^*$ did little change during storage regardless of the film kind. The TBA values of white bread packaged with chitosan or PHB(L) film slowly increased during storage. The springiness of white bread packaged with PHB(M), PHB(L) and chitosan film was high. The colony forming units of microorganisms for white bread packaged with chitosan film were low during storage. Therefore, PHB(M), PHB(L) and chitosan films were superior to PHB(H) and PHB films as package material for white bread.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1224-1229
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• 2004

The blend films of poly(3-hydroxybutyric acid) (PHB) with chitosan were prepared and water vapor transmission rate, oxygen permeability and lipid permeability of the PHB/chitosan films were measured. Additionally, the biodegradability of the PHB/chitosan films was also evaluated. Water vapor transmission rate and oxygen permeability of the films decreased by the addition of chitosan. The addition of polyethylene glycol (PEG, plasticizer), however, increased the water vapor transmission rate and oxygen permeability of the films. In the evaluation of lipid permeability, all the films except PHB (the film made of only PHB) and PHB-P (the film made of PHB and PEG) did not permeate beef tallow for 24 hours. The consumed oxygen for PHB/chitosan films during incubation was greater than that for the control on the biodegradability determination of the films, which implies that PHB/chitosan films were degraded by the microorganisms. The higher PHB ratio of the films was, the faster biodegradation of the films occurred.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.475-481
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• 2002

Blend films of poly(3-hydroxybutyric acid) (PHB) with chitosan were prepared, and their Physical properties and crystallization were investigated. The degree of crystallinity of PHB/chitosan films by X-ray diffraction decreased with increasing chitosan concentration. In the fourier-transformed infrared spectra, carbonyl peak of PHB became lower with increasing the amount of chitosan. The addition of chitosan to PHB film decreased thermal stability and crystallinity of the blend films. The granular sizes of the films were reduced with the addition of chitosan to the film in the microstructural observation by a scanning electron microscope. Mechanical properties, including tensile strength and percent elongation, of the blend films increased with increasing chitosan ratio in the films. For color of the films, L and b values generally decreased with increasing chitosan ratio, but transparency of the films increased.