Microwave-assisted extraction of phenolic compounds from tea residues under autohydrolytic conditions

Shuntaro Tsubaki, Masahiro Sakamoto, Jun ichi Azuma

Research output: Contribution to journalArticlepeer-review

77 Citations (Scopus)


Phenolic compounds were extracted from three kinds of tea residues (green, oolong and black tea residues) by microwave-assisted extraction in water under autohydrolytic conditions without using any catalyst or organic solvent. Productions of phenolic compounds were enhanced by microwave heating at 230°C. The main phenolic constituent in the extract from green tea residue was pyrogallol (24.6%) which was estimated to be originated from degradations of catechins. Derivatives of guaiacyl units of lignin such as dihydroconiferyl alcohol (10.3%) and vanillin (8.1%) were, however, the main constituents in oolong tea residue. In the case of black tea residue, derivatives of both catechins and lignin were comparably extracted. These phenolic compounds are interesting as a bio-based chemical feedstock such as phenolic precursors and antioxidants.

Original languageEnglish
Pages (from-to)1255-1258
Number of pages4
JournalFood Chemistry
Issue number4
Publication statusPublished - Dec 2010
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Analytical Chemistry
  • Food Science


Dive into the research topics of 'Microwave-assisted extraction of phenolic compounds from tea residues under autohydrolytic conditions'. Together they form a unique fingerprint.

Cite this