Chemical conversion of ginsenosides in puffed red ginseng

The effects of puffing process on chemical conversion of ginsenosides, extraction yields and crude saponin contents in red ginseng were investigated. To reach a maximum extraction yield, puffed red ginseng took only 8 h, while non-puffed red ginseng required at least 20 h showing extraction yields of 45.7 g solid extract/100 g sample and 44.5 g solid extract/100 g sample, respectively. Extraction yield increased slightly with increasing puffing pressure. Puffed red ginseng showed higher crude saponin contents (201.0–219.0 mg/g extract) than non-puffed one (161.7–189.0 mg/g extract). As the puffing pressure increased, minor ginsenosides (Rg3, F2, Rk1 and Rg5) increased but the contents of major ginsenosides (Rb1, Rb2, Rc, Rd, Re and Rg1) decreased. These results indicated that a puffing process may provide an effective method to reduce the extraction time, improve the extraction yield and increase the crude saponin content of red ginseng.