Abstract:

In order to achieve good taste and high nutritional value for mulberry leaf tea beverage, the extraction
simultaneous process of free amino acids and polyphenols from mulberry leaf tea using water as the extractant was optimized
by response surface methodology. The results showed that the optimal extraction temperature, water/tea ratio and extraction
time were 89 ℃, 87:1 (mL/g), and 16 min, respectively. Under these conditions, the extraction yields of free amino acids
and polyphenosl were experimentally determined to be 21.46 and 14.32 mg/g, respectively, which were both close to the
predicted values. These results indicate the quadratic polynomial mathematical model built by Design-Expert software was
accurate and feasible and the optimized extraction process was stable and reliable. This study can provide a reference for the
development of mulberry leaf tea beverage.

Key words: mulberry leaf tea, response surface methodology (RSM), polyphenols, free amino acids, extraction