| Summary: | 碩士 === 國立臺灣大學 === 食品科技研究所 === 94 === Oxygen is one of the major factors of the deterioration of foods. The presence of oxygen may decrease the shelf-life of the foods. Using oxygen scavengers on foods can reduce the undesirable effects caused by oxygen. The purpose of this study was to develop the oxygen scavenger film for liquid foods with natural material.
The major components of oxygen scavenger films are polymer, oxidizable compounds, and catalyst. In this study, mainly, the oxygen scavenging capacity and oxygen scavenging rate of the oxygen scavenger film in water were determined. Additionally, the compositions of the head space gas of packaging were measured for evaluating the performance of the films. The results showed that the film composed of low density polyethylene (LDPE), 2% green tea 50% methanol extracted powder, and 0.1% CuSO4 had the best oxygen scavenging efficiency. During 2 and 10 days, the oxygen removed rate of the film was 0.03844 mg/cm2 and 0.0964 mg/cm2, respectively, from 300 ml water. The oxygen scavenging efficiency of films produced by thermal compressor was as much as that made by the extruder.
The physical properties analyses conducted by Instron indicated that
addition of 2% green tea powder extracted with 50% methanol decreased the tensile strength and elongation of the LDPE film. On the other hand, cause we added nature antioxidant component to replace artificial antioxidant component, we have not to worry about metal migration problem. We filled the model solution into PP bottle, and the oxygen scavenger film or was used as the cap gasket. After storing at 4℃ for 15 days, the dissolved oxygen contents of the model solution were significantly lower than that of the control groups.
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