L-Theanine

L-Theanine is the amino acid that gives shaded green tea its brothy, umami character, making up roughly 1–2% of the dry weight of the leaf. Structurally it is the gamma-ethylamide of L-glutamic acid — N5-ethyl-L-glutamine — which is why it behaves like a glutamine analogue rather than a plain amino acid. Growers deliberately shade tea bushes before harvest to raise the theanine content, and that same amide chemistry is what determines its customs classification. Bulk L-theanine is not extracted from tea at commercial scale; the economics do not work. It is made enzymatically, using glutaminase or gamma-glutamyltranspeptidase to join L-glutamine or L-glutamic acid with ethylamine, a biocatalytic route that delivers the enantiomerically pure L-form. Buyers should insist on the specific rotation figure of +7.7° to +8.5° on every certificate: cheaper chemically synthesised material can be racemic DL-theanine, and rotation is the fastest way to tell the two apart. The enzymatic route is non-animal throughout. Regulatory footing is well established. Japan has permitted unrestricted use in all foods except infant food since 1964, and US FDA GRAS notices have covered use at up to 250 mg per serving since 2007. Formats we ship into are mostly beverage powders, ready-to-drink shots, capsules, chewables and gummies. Thovek supplies 98% and 99% minimum grades with HPLC assay, specific rotation, heavy-metal and residual-solvent data on every lot.