Development of theRhodiola rosea FuquandRhodiola roseasoy sauce, and the determination of their functional properties

Abstract

A mixed starter, composed of high-quality Rhodiola rosea Fuqu, was developed. Compared with normal Fuqu, Rhodiola rosea Fuqu demonstrated higher spore numbers, spore germination rates, protease activity, liquefying amylase activity and total acid and amino acid nitrogen. Specifically, the spore number was 1.36 times that of regular Fuqu. Protease activity, liquefying amylase activity, total acid and amino acid nitrogen were 0.475 g/100 mL, 104.16 U/g dry Qu, 35.67 mmol/L and 26.08 g/100 mL, respectively. These values were 21.48, 7.41, 6.07 and 67.82% higher than the regular Fuqu. The Rhodiola rosea soy sauce indices were also better than those for the control. The DPPH scavenging abilities of R. rosea soy sauce, control soy sauce, market soy sauce 1 and market soy sauce 2 were 74.25, 44.01, 34.73 and 11.38%, respectively. The total phenolic content in these four samples was 387.38, 309.23, 212.85 and 202.60 mg GAE/g, respectively. As observed with the DPPH and total phenolic assay, the R. rosea soy sauce showed the highest antioxidant capacity. A simple, rapid, and sensitive determination method of salidroside in R. rosea Fuqu and R. rosea soy sauce using HPLC-ESI-MS/MS was developed and validated with multiple reaction monitoring in the negative mode.