Effect of saccharides on sediment formation in green tea concentrate

- Addition of sugar reduced the sediment amount of green tea concentrate.
- Sugars competitively participated in sediment formation with polyphenols/caffeine.
- Sugars with fructosyl had better effect on inhibiting sediment formation.
- The phenomenon was elucidated by 1H-NMR spectrum and interaction energy.

Reducing sediment in green tea concentrate utilized for tea production is an important process. In this study, the effect of saccharides on sediment formation in green tea concentrate was investigated. The results show that the amount of tea sediment significantly decreased (31.4%-86.4%) with the addition of fructose or sucrose and that the ratios of polyphenols and caffeine in the sediment sharply decreased (24.1%-49.7% and 2.4%-6.2%) while the proportion of total sugars markedly increased (20.9%-56.5%) in the sediment. Moreover, fructosyl was found to be a highly effective functional group for preventing sediment formation, on the basis of experimental results for a series of sugars with different numbers of fructosyl groups. This phenomenon was elucidated from the energies of interaction between typical sugars, polyphenols, and caffeine calculated by density functional theory method. Our results open new applications for tea concentrates.