微波-热风联合干燥方法对兰州百合品质的影响

Effect of microwave combined hot-air drying method on the quality of Lilium davidii var. unicolor

中文关键词:  兰州百合  品质  热风干燥  微波干燥  微波-热风联合干燥

英文关键词:Lilium davidii var. unicolor  quality  hot-air drying  microwave drying  microwave combined hot-air drying

中文摘要:

      目的 探究微波-热风联合干燥方法加工兰州百合的可行性, 并对加工的兰州百合干进行品质评价。方法 从干燥动力学、色泽L*、复水比3个方面对热风干燥温度、微波干燥功率、微波-热风联合干燥的干燥顺序及含水量转换点进行考察, 筛选出兰州百合最优干燥工艺后, 对最优工艺干燥样品、硫熏样品和无硫样品的品质进行分析比较。结果 先213 W微波干燥, 后60℃热风干燥, 40%的百合含水量转换点为微波-热风联合干燥最优工艺, 相较直接60℃热风干燥可缩短33%的干燥时间。相较硫熏样品, 微波-热风联合干燥样品的感官评分、复水比、蛋白质及维生素C (vitamin C, VC)含量分别提高了16.93%、40.54%、25.72%和26.28%, 色泽L*、b*间差异不显著; 相较无硫样品, 微波-热风联合干燥样品的感官评分、色泽L*、复水比、蛋白质及VC含量分别提高了13.43%、3.97%、33.33%、24.44%和19.89%, 而b*显著降低了9.58%。结论 微波-热风联合干燥不仅可有效地缩短干燥时间, 还可获得高品质的百合干, 是一种具有发展前景的兰州百合干制方法。

英文摘要:

      Objective To investigate the feasibility of microwave combined hot-air drying for Lilium davidii var. unicolor, and evaluate the quality of processed lily. Methods The effect of drying temperature, microwave drying power, the drying sequence and water content conversion point of microwave combined hot-air drying on drying characteristics, color (L*) and rehydration ratio were studied for screening optimal compound drying technology. Quality of the optimal process dried samples, sulfur-fumigated samples and sulfur-free samples were also comparatively analyzed. Results The results showed that the optimal compound drying process was 213 W microwave followed by hot-air drying at 60℃, and the water content conversion point of Lilium davidii var. unicolor was 40%, the drying time could be shorten by 33% than hot-air drying at 60℃. The sensory score, rehydration ratio, protein and vitamin C (VC) content of dried lily by microwave combined hot-air method were 16.93%, 40.54%, 25.72% and 26.28%, respectively, higher than that in sulfur-fumigated samples, there was no significant difference in L* and b*. Compared with the sulfur-free samples, the sensory score, L* rehydration ratio, protein and VC content of lily dried by the microwave combined hot-air drying process was increased by 13.43%, 3.97%, 33.33%, 24.44% and 19.89%, respectively. Whereas b* was significantly reduced by 9.58% than the sulfur-free samples. Conclusion Microwave combined hot-air drying can not only effectively shorten the drying time, but also obtain high-quality dried lily, which is a promising drying method for Lilium davidii var. unicolor.