TY - JOUR
T1 - Non-targeted analysis by LC–MS of major metabolite changes during the oolong tea manufacturing in New Zealand
AU - Fraser, Karl
AU - Lane, Geoff A.
AU - Otter, Don E.
AU - Harrison, Scott James
AU - Quek, Siew-Young
AU - Hemar, Yacine
AU - Rasmussen, Susanne
PY - 2014
Y1 - 2014
N2 - Oolong tea is a semi-fermented tea that is partially oxidised during the manufacturing process to create a product unique in composition. In this study, we investigated the potential of non-targeted LC–MS with two complementary chromatographic modes to provide a “comprehensive and unbiased” view of biochemical compositional changes occurring during oolong tea manufacturing in New Zealand. Tea leaf samples from throughout the manufacturing/fermentation process during three different harvest periods (spring, summer and autumn) were analysed by four different LC–MS streams. Principal component analysis revealed the de-greening stage of the manufacturing process was responsible for major changes in the biochemical profile, with the methodology detecting changes in a wide range of metabolites of differing polarities, such as flavonoids, nucleosides and primeverosides. Changes during the fermentation phase of the manufacturing process were less marked, however significant increases in levels of free amino acids, a hydroxyjasmonic acid and related metabolites were observed.
AB - Oolong tea is a semi-fermented tea that is partially oxidised during the manufacturing process to create a product unique in composition. In this study, we investigated the potential of non-targeted LC–MS with two complementary chromatographic modes to provide a “comprehensive and unbiased” view of biochemical compositional changes occurring during oolong tea manufacturing in New Zealand. Tea leaf samples from throughout the manufacturing/fermentation process during three different harvest periods (spring, summer and autumn) were analysed by four different LC–MS streams. Principal component analysis revealed the de-greening stage of the manufacturing process was responsible for major changes in the biochemical profile, with the methodology detecting changes in a wide range of metabolites of differing polarities, such as flavonoids, nucleosides and primeverosides. Changes during the fermentation phase of the manufacturing process were less marked, however significant increases in levels of free amino acids, a hydroxyjasmonic acid and related metabolites were observed.
U2 - 10.1016/j.foodchem.2013.11.054
DO - 10.1016/j.foodchem.2013.11.054
M3 - Journal article
SN - 0308-8146
VL - 151
SP - 394
EP - 403
JO - Food Chemistry
JF - Food Chemistry
ER -