Abstract：
The pH-response color-changeable films were prepared by adding different contents (1 %, 2 % and 3 %) of hyacinth bean anthocyanins (HBA) into guar gum/polyvinyl alcohol blend matrix. The structural characterization and optical, barrier, mechanical, thermal, antioxidant and color-changeable properties of the films were determined. The films were applied to monitor the freshness of chilled shrimp and pork. Results showed that HBA were pH-dependent color-changeable pigments that endowed the films with purple color. 2 % and 3 % of HBA improved the uniformity and compactness of the films by forming hydrogen bonds with film matrix. The barrier ability of the films against UV-vis light, water vapor and oxygen was significantly elevated by 2 % and 3 % of HBA. The mechanical, thermal and antioxidant properties of the films were improved by HBA. The films containing HBA were much sensitive to pH variation and ammonia vapor, presenting obvious color changes (purple→green→yellow-green). The films containing HBA showed good color stability when stored at 4 °C for 30 days. Moreover, the film containing 2 % HBA showed color changes (purple→green) when the chilled shrimp and pork decayed. The results suggested that the film containing 2 % HBA was suitable to monitor the freshness of meat products in intelligent packaging field.
摘要：
通过添加不同含量（1％，2%和3%)的风信子豆花色苷(HBA)加入瓜尔胶/聚乙烯醇共混基质。结构表征和光学,屏障,机械,热,测定了薄膜的抗氧化性能和变色性能。该膜用于监测冷藏虾和猪肉的新鲜度。结果表明，HBA是pH依赖性的变色颜料，赋予薄膜紫色。2%和3%的HBA通过与薄膜基体形成氢键，提高了薄膜的均匀性和致密性。薄膜对紫外线的阻挡能力，水蒸气和氧气显著升高2%和3%的HBA。机械的,HBA改善了薄膜的热性能和抗氧化性能。含HBA的薄膜对pH变化和氨蒸气非常敏感，呈现明显的颜色变化（紫色→绿色→黄绿色）。当在4°C下储存30天时,含有HBA的膜显示出良好的颜色稳定性。此外，当冷冻虾和猪肉腐烂时，含有2％HBA的薄膜显示出颜色变化（紫色→绿色）。结果表明，含2％HBA的薄膜适用于智能包装领域肉制品新鲜度的监测。
