milk_lover
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- Joined
- Aug 15, 2015
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This study (see attachment below) claims that addition of only 50 ml milk to tea (the source of L-theanine) is enough to cause a significant reduction of free L-theanine extracted from tea due to a binding process. It continues to say it is unknown if L-theanine would be released again in the gut and be absorbed by the body. 12 ml of milk apparently didn't reduce free L-theanine. I know some of us take L-theanine with coffee, so just to be on the safe side, one might consider drinking the coffee without milk or with little milk. BTW, the study said black tea has more L-theanine than green tea!
"Experiment 5 investigated the effects of the addition of milk on the amounts of L-theanine extracted. The fat content of milk had only a small effect on the amount of L-theanine extracted from tea prepared in the standard manner. Amounts of L-theanine extracted are as follows: no milk (24.8 ± 0.73 mg/200 ml), skimmed milk (26.8 ± 1.76 mg/200 ml), semi-skimmed milk (24.5 ± 2.13 mg/200 ml) and full-fat milk (27.1 ± 3.31 mg/200 ml). Statistical analysis revealed no significant differences between these amounts. The volume of milk added, however, did affect the amount of L-theanine extracted (p < 0.0001). Fig. 2 shows that addition of 50 ml semi-skimmed milk greatly reduced the amount of L-theanine extracted (p < 0.0001, Tukey post hoc test). From examination of the chromatograms in Fig. 3 it appears that addition of 50 ml milk caused the appearance of a less polar peak. It is suggested that the amount of free L-theanine has decreased due to a binding process. It is unknown whether the L-theanine would be irreversibly bound or would be released again in the gut and still be absorbed by the body. Further analysis is required to determine the amount of L-theanine available for absorption when tea is prepared with a large amount of milk. The recommended standard amount of milk added to a tea preparation is 12 ml (Tetley Tea) and this made no significant difference to the amount of L-theanine extracted."
"Experiment 5 investigated the effects of the addition of milk on the amounts of L-theanine extracted. The fat content of milk had only a small effect on the amount of L-theanine extracted from tea prepared in the standard manner. Amounts of L-theanine extracted are as follows: no milk (24.8 ± 0.73 mg/200 ml), skimmed milk (26.8 ± 1.76 mg/200 ml), semi-skimmed milk (24.5 ± 2.13 mg/200 ml) and full-fat milk (27.1 ± 3.31 mg/200 ml). Statistical analysis revealed no significant differences between these amounts. The volume of milk added, however, did affect the amount of L-theanine extracted (p < 0.0001). Fig. 2 shows that addition of 50 ml semi-skimmed milk greatly reduced the amount of L-theanine extracted (p < 0.0001, Tukey post hoc test). From examination of the chromatograms in Fig. 3 it appears that addition of 50 ml milk caused the appearance of a less polar peak. It is suggested that the amount of free L-theanine has decreased due to a binding process. It is unknown whether the L-theanine would be irreversibly bound or would be released again in the gut and still be absorbed by the body. Further analysis is required to determine the amount of L-theanine available for absorption when tea is prepared with a large amount of milk. The recommended standard amount of milk added to a tea preparation is 12 ml (Tetley Tea) and this made no significant difference to the amount of L-theanine extracted."
