pH值对保鲜纸中亚氯酸钠留存率和二氧化氯释放规律的影响

通过调节亚氯酸钠涂布液pH值，探究pH值对保鲜纸中亚氯酸钠留存率和ClO2释放规律的影响。采用碘量 滴定法计算A纸（涂布亚氯酸钠）中亚氯酸钠的留存率和保鲜体系中ClO2的释放量，并对A、B纸（涂布酒石酸）的 表面进行傅里叶变换衰减全反射红外光谱分析。结果表明：随着涂布液pH值的增加，A纸中亚氯酸钠的留存率显著 增加，当pH 14时，亚氯酸钠的留存率最大，留存时间最长。随着pH值的增大，ClO2与纸基成分的反应量增大，保 鲜体系中ClO2的释放总量减少，释放时间先延长后缩短，释放速率先快后慢。当涂布液pH 10时，体系中ClO2的释 放时间最长；同时，在涂布液pH 10时，ClO2释放速率和释放量的特点保证了保鲜体系中ClO2的浓度，有利于果蔬 的保鲜。

Effect of pH on NaClO2 Retention Rate and ClO2 Release Rate in Preservative Paper

This work was conceived to investigate the effect of pH on NaClO2 retention rate and ClO2 release rate in preservative paper through adjusting the pH of NaClO2 coating solution. The NaClO2 retention rate from paper A coated with sodium chlorite and the ClO2 release rate from the preservation system were calculated by iodometric titration method. In addition, the surface of paper A and paper B coated with tartaric acid was analyzed by attenuated total reflection infrared (ATR-IR) spectroscopy. The results showed that with the increase of pH, the NaClO2 retention rate from paper A and the amount of ClO2 reacting with preservative components increased significantly. On the contrary, the total amount of ClO2 release from the preservation system decreased. At pH 14, the NaClO2 retention rate was the highest, and the retention time was the longest. Besides, the release time initially increased and afterwards decreased, and the release rate was initially high and then decreased. At pH 10, ClO2 was released for the longest time, and the release rate and amount could guarantee ClO2 concentration for the preservation of fruits and vegetables.