Quality Characteristics of Rehmannia radix Preparata with Pre-soaking Solvents

침지용매에 따른 숙지황의 품질특성

  • Woo, Koan-Sik (Department of Food Science and Technology, Chungbuk National University) ;
  • Song, Dae-Sik (Shinwon Food Industry Co.) ;
  • Lee, Jun-Soo (Department of Food Science and Technology, Chungbuk National University) ;
  • Lee, Hee-Bong (Department of Food Science and Technology, Chungbuk National University) ;
  • Jeong, Heon-Sang (Department of Food Science and Technology, Chungbuk National University)
  • Published : 2007.06.30


This study was performed to investigate the effects of pre-soaking methods on the preparation of Rehmannia radix Preparata (R.P). The R. radix L (R.L) was soaked in distilled water and traditional Korean wine for 24 hr, then the soaked R.L was treated with a traditional nine-time steaming process. Next, catalpol, 5-hydroxymethyl-2-furaldehyde (5-HMF), polyphenols, flavonoids, antioxidant activities, and ACE inhibition activity were analyzed for the R.P produced by the different methods. The catalpol content of the R.L was 631.4 ppm, but the content decreased as steaming increased to 8-9 times. The 5-HMF, polyphenol, and flavonoid contents of the R.L were 0.12 mg/g, 5.09 mg/g, and 0.83 mg/g, respectively, and these increased gradually with increasing steaming times. As the steaming times of the distilled soaking water increased, the antioxidant activities of 1 mg/mL increased from 19.44% to 75.60% at 14 times of steaming. The ACE inhibition activities of 1 mg/mL of the distilled soaking water increased from 28.70% to 94.78% at 10 times of steaming, but decreased afterward.


Rehmannia radix;pre-soaking method;catalpol;5-HMF;antioxidant activities;ACE inhibition


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