pH响应性食品包装材料的制备及其对酸性气体的识别指示性研究

目的 针对食品新鲜度下降过程产生的酸性气体(以CO2为例)进行识别和指示.方法 以高直链玉米淀粉、聚乙烯醇及交联剂等多种助剂为原料,负载pH响应性复合指示剂,利用高分子溶液聚合方式制得高直链玉米淀粉基pH响应性食品包装材料,简称HASF.结果 对HASF指示材料透光性、吸水性、水溶性、力学性能进行分析,确定最佳比例;通过对指示材料CO2的识别检测,确定复合指示剂中甲基红与溴百里酚蓝最优体积比为1:2,最佳体积分数为6％;指示材料的红外光谱和扫描电镜显示,材料内部各组分间分散均匀,性质统一,相容性良好,该食品包装复合膜的性能稳定.结论 HASF指示材料可适用于食品包装材料.同时,HASF指示材料可通过颜色转变对酸性气体进行识别和指示,为食品包装材料智能化提供了可能.

Preparation of pH-Responsive Food Packaging Materials and Study of Acid Gas Indication

The aim is to identify and indicate the acidic gas (CO2 for example) generated during the process of food freshness decline. High amyloid-based pH responsive food packaging materials (HASF for short) prepared by the method of polymer solution polymerization are made from high amylose corn starch, polyvinyl alcohol, crosslinking agent and other auxiliaries and pH responsive composite indicators. The light transmittance, water absorption, water solubility and mechanical properties of the HASF indicator material are analyzed to determine the optimal ratio. Through the identification and detection of CO2 by the indicator materials, the volume ratio of methyl red to bromothymol blue in the composite indicator is determined to be 1 : 2 and the optimal additive amount is 6%.The infrared spectrum and scanning electron microscope show that the internal compatibility of the components is good. Therefore, the performance of the food packaging composite film is stable. The indicator materials can be used for food packaging materials. At the same time, the indicator materials can identify and indicate acid gas through color change, which provides the possibility for the intelligence of food packaging materials.