FOOD SCIENCE ›› 2013, Vol. 34 ›› Issue (14): 35-39.doi: 10.7506/spkx1002-6630-201314008

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Preparation of Tea Polyphenols from Summer-Autumn Low-Grade Tea by Countercurrent Extraction Using Rotary Disc Extractor

WEI Zhe,XIAO Wei,LI Zhong-jian,WANG Jun,WU Fu-an   

  1. 1. School of Biology and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212018, China;
    2. Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang 212018, China
  • Received:2012-06-19 Revised:2013-05-06 Online:2013-07-25 Published:2013-08-02

Abstract:

The applicability of the countercurrent rotary disc extractor was examined in this study for liquid-liquid extraction of tea polyphenols (TPs) from summer-autumn low-grade tea. Crude aqueous extracts were prepared and operating parameters including extraction solvent, initial solvent pH, extraction temperature, back extraction temperature and rotation speed were explored. The results indicated that the best conditions for liquid-liquid extraction of TPs were addition of the same volume of the extraction solvent glyceryl triacetate to crude aqueous extract at pH 3.17, extraction at 10 to 20 ℃ and back extraction at 70 to 80 ℃ with a rotation speed of 200 r/min. The recovery rate of TPs was 18.9% after 5 h extraction under the optimized conditions. The advantages of the developed countercurrent extraction process using rotary disc extractor are characteristics of short process flow, low investment, low cost, low energy consumption, environmental friendliness and high efficiency.

Key words: tea polyphenols, low-grade tea, rotary disc extractor, countercurrent extraction

CLC Number: