L-Theanine 98%

Tea plants accumulate L-theanine in the young leaf as a free amino acid, and this L-theanine is isolated from the leaf of Camellia sinensis by solvent extraction and purification. It is a non-protein amino acid, formally N5-ethyl-L-glutamine, so its structure is glutamic acid carrying an ethylamide on the side chain.

The primary grade is 98% L-theanine by HPLC, in Food / Dietary Supplement Grade. The white powder is water soluble, which sets it apart from the polyphenol-rich tea extracts that share its botanical source. It is used where the single amino acid, and not a mixed tea extract, is the defined ingredient.

L-Theanine Chemical Identity

L-Theanine has the molecular formula C7H14N2O3 and a molecular weight of 174.2. Because the ethylamide sits on the side-chain carboxyl, the molecule keeps one free amino group and one free carboxyl group and behaves as a zwitterion in water. The L at the front of the name marks the (2S) configuration that tea plants make. The mirror-image D-form is a different compound with a different identifier, and it is not what a tea leaf produces.

The natural source is the leaf of Camellia sinensis (L.) Kuntze, where theanine is one of the main free amino acids and is thought to be made in the root and carried to the shoots. L-Theanine can also be produced by enzymatic or chemical synthesis, which is why the source belongs beside the name. Tea itself is supplied in other forms: Green Tea Extract 40–98% Polyphenols, Black Tea Extract 10–40% Theaflavins and the 10:1 Green Tea Extract Powder. Those materials are defined by polyphenols, and L-theanine itself is a separate, purified compound with its own identifiers. Shading tea plants before harvest raises the theanine level of the young leaf, which is why shade-grown teas are rich in the amino acid and why cultivation affects the starting material.

Typical Specifications

Specification ItemProduct Information
Natural SourceCamellia sinensis leaf
Plant PartLeaf & Herb
ProcessingSolvent Extraction & Purification
Chemical Name (IUPAC)(2S)-2-amino-5-(ethylamino)-5-oxopentanoic acid
CAS Number3081-61-6
Molecular FormulaC7H14N2O3
Molecular Weight174.2
PubChem CID439378
InChIKeyDATAGRPVKZEWHA-YFKPBYRVSA-N
SMILESCCNC(=O)CCC(C(=O)O)N
Purity98% (HPLC)
GradeFood / Dietary Supplement Grade
AppearanceWhite powder
Solubility / DispersibilityWater Soluble
Quality Parameters
Moisture (LOD)≤5.0%
Total Ash≤5.0%
Heavy MetalsLead ≤2 ppm · Arsenic ≤1 ppm · Cadmium ≤1 ppm · Mercury ≤0.1 ppm
MicrobiologyTPC ≤1,000 cfu/g · Yeast & Mold ≤100 cfu/g · E. coli Negative · Salmonella Negative/25 g
Shelf Life24 months in unopened original packaging, cool and dry storage

L-Theanine Purity Grades & Impurities

The 98% figure is an HPLC result, and the method needs some care because L-theanine absorbs only weakly in the ultraviolet range. Laboratories either read at a short wavelength, where many other compounds also respond, or derivatize the amino group before detection, and the choice decides which impurities are seen. The percentage compares the theanine peak with the other detected peaks. It leaves out water, ash and any component without a response, so moisture and ash are limited separately in the table.

The related substances of a tea-derived amino acid are other amino acids, above all glutamic acid and glutamine, with traces of arginine and alanine that follow theanine through purification. Pyroglutamic acid forms when a glutamyl compound cyclizes under heat and acid, so it is read as a sign of overheating. Carry-over from the leaf, such as caffeine and catechins, is removed in purification and checked as a residue.

Chirality is a separate point. A chromatographic purity figure does not separate D- from L-theanine on an ordinary column, so enantiomeric purity is checked with a chiral column or by optical rotation. Material taken from tea is the L-form, while some synthetic routes can give a racemic mixture. Stating the natural source and the L- prefix together tells a buyer which of the two materials is on offer.

An HPLC trace for L-theanine is read together with the identity data. Retention time against a reference standard, the response after derivatization and the optical rotation of the lot together separate the amino acid from glutamine and from other glutamyl amides of similar mass. A lot that passes on area share alone but fails on chirality would not be the same ingredient.

L-Theanine Solubility & Delivery

L-Theanine dissolves freely in water and poorly in ethanol and less polar solvents, so it is handled as a water-phase ingredient. The solution is clear and colorless, and the taste is mild, faintly sweet and savory, with little bitterness. The molecule is a zwitterion with a low logP, which keeps it out of oil phases and rules it out as a lipid-soluble ingredient. In the neutral to mildly acidic range of most drinks it is stable. Strong acid or base combined with long heating hydrolyzes the amide to glutamic acid and ethylamine, so thermal steps should be short.

For delivery, a freely soluble amino acid needs no co-solvent or carrier. In capsules and tablets it is a fine crystalline powder that flows moderately and takes up a little moisture. In drink powders it dissolves without haze, so it suits clear drinks and shots that polyphenol-rich tea extracts cannot serve. It blends easily with other amino acids and sweeteners, and its mild taste is masked by the neighbors in the blend and not by encapsulation.

Aqueous stocks are best made at moderate temperature, then filtered and refrigerated, since amino acids feed spoilage organisms. Dry blends are less demanding, although the powder lumps if it is stored open in humid rooms, and a premix with a dry carrier keeps small weights accurate during filling.

Application Areas

Capsules and Tablets

L-Theanine fills capsules and presses into tablets at low to moderate inclusion. The crystalline powder flows adequately, but it can pick up moisture, so a dry room and a desiccant in the bottle protect tablet hardness and prevent caking of the fill.

Clear Drink Powders

Because the amino acid dissolves without haze, it fits clear water-based drink powders and shots. Dissolve it in the warm water phase before the acid is added, and keep thermal steps short to avoid slow loss to glutamic acid.

Powder Stick Blends

Sticks and sachets carry L-theanine in tea-style or flavored drink mixes. A two-step premix with a dry carrier gives uniform weight at small inclusion, and a sweetener or fruit acid covers the faintly savory note.

Gummy Premixes

Gummies take the amino acid at gram level. Add it to the mass after the cook, because long heating at low pH can degrade it, and check clarity of the finished piece against the control batch.

Packaging & Commercial Supply

Essencefield supports product evaluation, formulation trials, commercial orders, and ongoing ingredient supply. Packaging, storage, and shipping arrangements are determined by product characteristics, order quantity, stability requirements, and destination-market needs.

Supply ItemGeneral Information
SampleAvailable upon request for formulation, testing, and supplier evaluation
Order Quantities100 g · 1 kg · 5 kg · 25 kg · 100 kg · 500 kg · Bulk
Sample Lead TimeTypically 5–7 days after sample confirmation
Production Lead TimeTypically 15–30 days after order and specification confirmation
PackagingSuitable protective inner packaging with bags, cartons, drums, or other appropriate outer packaging
StorageStore in tightly sealed, suitable protective packaging in a cool, dry environment. Protect from moisture, heat, and direct sunlight. Specific storage conditions follow the approved product specification.
DocumentationCOA · Product Specification · TDS · SDS · Applicable declarations (as applicable)

Final order quantities, lead times, packaging, documentation, and shipping arrangements are confirmed according to the selected product and commercial requirements.

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