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Chemical constituents of Oolong tea produced in Thailand and their correlation with infusion colour |
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| รหัสดีโอไอ | |
| Creator | Theerapong Theppakorn |
| Title | Chemical constituents of Oolong tea produced in Thailand and their correlation with infusion colour |
| Publisher | Maejo University |
| Publication Year | 2558 |
| Journal Title | Maejo International Journal of Science and Technology |
| Journal Vol. | 9 |
| Journal No. | 3 |
| Page no. | 344 |
| Keyword | chemical contituents of tea,tea infusion colour,Oolong tea,Thailand |
| ISSN | 1905-7873 |
| Abstract | Constituents expected to influence the colour of tea infusion, namely total polyphenols, total catechins, eight individual catechins, theaflavins and chlorophylls were determined in 28 samples of Oolong tea manufactured in Thailand. The colours attributes (L*, a*, b*, hue angle and absorbance at 420 nm) of the infusions were measured and the correlation between the constituents and infusion colours was determined. The correlation analysis indicates that theaflavins and chlorophylls strongly correlate with infusion colours but total polyphenols and total catechins do not. Theaflavins correlate negatively with L* and positively with a* and b*. Chlorophylls correlate positively with the L* but negatively with a*, b* and hue angle. Chlorophylls and theaflavins were found to be the most important constituents contributing to the colour of Oolong tea manufactured in Thailand. |