不同干燥方式对祁菊花品质的影响

Effects of different drying methods on the quality of Chrysanthemum morifolium

目的 考察不同干燥方式对祁菊花品质的影响,为祁菊花的采收加工提供依据。方法 采用7类共25种干燥方式对祁菊花鲜品进行干燥得到25种样品,以其外观性状及含水量为淘汰指标,去除不合格样品;以6种有效成分(绿原酸、木犀草苷、3,5-O-咖啡酰基奎宁酸、槲皮素、木犀草素、黄芩苷)的含量为指标,结合主成分分析(PCA)及偏最小二乘法-判别分析(PLS-DA),以及PCA综合得分排名及每类干燥方式所得的最佳样品,综合选择6种实验样品;以氧化相关酶(多酚氧化酶、过氧化物酶)活性、稳定性及花瓣表面微观形态为指标,对上述6种样品进行质量评价。结果 PCA与PLS-DA结果表明,不同干燥方式所得样品的质量存在明显差异,绿原酸、3,5-O-咖啡酰基奎宁酸、黄芩苷这3种成分可能是导致样品产生差异的主要原因,100℃蒸汽杀青1 min后再以50℃烘干4 h所得样品中有效成分的综合得分最高。经微波功率800 W杀青1 min后再以50℃鼓风干燥4 h与100℃蒸汽杀青1 min后再以50℃烘干4 h这2种联合干燥方式处理的祁菊花中氧化相关酶完全失活,稳定性优于其他干燥方式所得样品;花瓣表面微观形态观察结果显示,以微波功率400 W烘干6 min所得样品与上述2种样品的完整度、平整度最高。结论 从成品质量及干燥效率来看,以100℃蒸汽杀青1 min后再以50℃烘干4 h是祁菊花的最佳干燥方式。

OBJECTIVE To investigate the effects of different drying methods on the quality of Chrysanthemum morifolium,and to provide a basis for the harvesting and processing of C.morifolium.METHODS Twenty-five samples were obtained by drying the fresh products using 7 types and 25 kinds of drying methods,and the unqualified samples were removed by taking their appearance and moisture content as elimination indexes.The contents of six active ingredients(chlorogenic acid,luteoloside,3,5-O-dicaffeoylquinic acid,quercetin,lignoceroside,baicalin)were used as indicators,and combined with principal component analysis(PCA),partial least square method-discriminant analysis(PLS-DA),PCA comprehensive score ranking and the best samples obtained from each drying method to select 6 experimental samples comprehensively.The quality of 6 kinds of samples was evaluated using the activities and stability of oxidation-related enzymes(polyphenol oxidase,peroxidase)and the microscopic morphology of the petal surface as evaluation indexes.RESULTS The results of PCA and PLS-DA showed significant differences in the quality of samples obtained by different drying methods,and chlorogenic acid,3,5-O-dicaffeoylquinic acid and baicalin might be the main reasons for the differences among the samples.The herbs treated with 100℃steam fixation for 1 min combined with blast drying at 50℃for 4 hours had the highest comprehensive score of active ingredients.The oxidation-related enzymes in C.morifolium treated with microwave 800 W fixation for 1 minute followed by 50℃air drying for 4 hours and 100℃steam sterilization for 1 minute followed by 50℃drying for 4 hours were completely inactivated,and the stability was better than that of samples obtained by other drying methods.The observation results of the microstructure of the petal surface showed that the sample obtained by drying at a microwave power of 400 W for 6 minutes had the highest integrity and flatness compared to the above two samples.CONCLUSIONS From the perspective of finished product quality and drying efficiency,100℃steam fixation for 1 min combined with blast drying at 50℃for 4 hours is the best drying method for C.morifolium.