Study on the Extraction of Fermented Pu-erh Tea Polyphenols with Different Solvents

The article using anhydrous ethanol,distilled water,different volume fractions of aqueous ethanol solvent to extract tea polyphenols from Pu-erh tea(fermented tea). Four factors,including extraction temperature,extraction time,solid-liquid ratio and different concentrations of aqueous ethanol,on the basis of single-factor test to determine the level of orthogonal experiment. By orthogonal experiments and comparative analysis,the contribution rates of the four factors on the extraction of tea polyphenols and their differences were studied. The results showed that the extraction mass fraction of tea polyphenols was the highest 13. 86% by the aqueous ethanol,by distilled water was the second 9. 67%,and the lowest was 5. 49% by anhydrous ethanol.