棣棠叶片压花保色技术研究

以棣棠叶片为试材，研究了5种不同干燥方法的压制效果以及5种不同化学保色剂的保色作用。结果表明，不同干燥方法对棣棠叶片的干燥效果不同，其中熨斗干燥法压制的叶片颜色鲜艳、平整，质感好，用时短，操作简单，最适合棣棠叶片的压制；其次是干燥板干燥法；其他3种方法不适合棣棠叶片压制。化学保色剂中，硫酸铜保色效果最佳，不同浓度硫酸铜处理均有一定程度的保色效果，其中5%硫酸铜处理12 h,经30 d强光照射后，叶片几乎无褪色，与对照颜色最接近，保色效果最好；其次是葡萄糖，5%葡萄糖处理16 h也获得较好的保色效果，其他浓度葡萄糖处理没有明显的保色作用；蔗糖、麦芽糖和氯化钙对棣棠叶片保色无效。

Study on the technology of color-keeping on pressed leaves of Kerria Japonica

Effects of five different drying methods and five kinds of chemical preservative were studied by using the leaves of Kerria japonica as the materials. The results showed that the effects on pressed leaves of K. Japonica were different with different drying methods. Among the methods, the iron drying method was the most suitable for the leaves of K. japonica for the bright color, smooth, good texture, short time and simple operation. The second was embossing board drying method. The other three methods were not suitable for the leaves pressing of K. japonica. Among chemical color preservatives, copper sulfate had the best color preservation effect. Different concentrations of copper sulfate treatment had a certain degree of color retention effect. Among them, the effect of 5% copper sulfate treatment for 12 hours was the best, leaves color was the closest to the control and showed almost no fade after 30 days under strong light irradiation. Next, glucose had certain effect to color-keeping. The treatment of 5% glucose soaked 16 hours also got better color-keeping effect. Other concentrations of glucose treatment had no obvious color preservation effect. The treatments of sucrose, maltose and calcium chloride had no effect on the preservation of color-keeping of leaves of K. japonica.