Study On The Drying Technology For Two TCM Materials That Are Rich In Starch In Dioscorea Opposita Thunb. And Fritillaria Thunbergii Miq.

Drying process of TCM materials is an important part of its medicinal formation.Drying of TCM materials that are rich in starch is the difficult and weak link of TCM materials drying.Rhizoma dioscoreae and Bulbus fritillaria thunbergii are commonly used TCM materials that are rich in starch,and starch contents ranged from 60%to80%.We studied the effects of different drying methods on the starch-related properties,active ingredients contents and pharmacological function of Rhizoma dioscoreae and Bulbus fritillaria thunbergii.The effects of five different drying processes,air drying?AD?,sulphur fumigation drying?SFD?,hot air drying?HAD?,freeze drying?FD?and microwave drying?MWD?for yams in terms of starch-related properties and antioxidant activity were studied.The results showed that allantoin content of HAD sample was as high as 2.57%,total soluble phenolic contents and the reducing power of HAD sample were higher,the values were1.06mg CE/g and 193.88?mol AC/g,respectively.The microwave drying caused the gelatinization of starch granules,thus it was not suitable for Rhizoma dioscoreae drying.On the basis of this,we studied the effects of AD,SFD,HAD,FD on the starch properties.The results showed that the resistant starch content of FD sample was as high as 88.49%.According to comparing the effects on the yams quality and the production costs of those drying methods,we found hot air drying yams had better quality,and hot air drying method is easy to promote in the processing of origin.We further study the effects of different hot air drying temperatures on the antioxidant activities,main bioactive components,and the starch-related physicochemical properties of yams.The results showed that the sample of hot air drying at 40oC?H-40?had higher contents of total flavone,soluble polyphenol,stronger reducing power,while the drying time was long.The sample of hot air drying at 60oC?H-60?had higher allantoin content,and other ingredients also had well retained.The results of drying kinetics showed that Page model provided superior simulation of the drying kinetics of Rhizoma dioscoreae.Model fitting results showed allantoin degradations were followed the first-order kinetic,the value of rate constant K_D at 60oC was lower(9.33×10^-6),half-life t_1/2 at 60oC was higher?1238.8min?,temperature coefficients Q_10?40/60?and Q_10?60/80?were 0.9693 and 1.8035,respectively.These phenomenon indicated that degradation ratio of allantoin was low when drying temperature below 60oC.In conclusion,hot air drying at 60oC was better drying method for Rhizoma dioscoreae.We studied the effects of six different drying methodes,sun drying?AD?,sulphur fumigation drying?SFD?,hot air drying?HAD?,freeze drying?FD?,microwave drying?MWD?and infrared drying?IRD?,on Bulbus fritillaria thunbergii quality.The results showed that the contents of the sum of peimine and peiminine,and resistant starch in hot air drying sample were higher than others,the value was 0.245%and 62.59%,respectively.What's more,the stronger eliminating phlegm and stopping cough activity was found in hot air drying sample.We further studied the drying kinetics of hot air drying for Bulbus fritillaria thunbergii.The results showed that both Page model and Wang-Singh model provided superior simulation of the drying kinetics curves.The sum content of peimine and peiminine was 0.144%in hot air dried at 60oC,which was the highest in dried samples at different temperatures.In conclusion,hot air drying at 60oC was better drying method for Bulbus fritillaria thunbergii.The results of this study provide a theoretical basis for large-scale drying of Rhizoma dioscoreae and Bulbus fritillaria thunbergii,and can be as a reference for other herbs,which are rich in starch.