Buyer summary: Green tea extract grades should be selected by the required marker, dosage form and target specification. A 20%, 50% or 98% tea-polyphenol grade defines different marker concentrations; a 20% L-theanine grade targets a different constituent; and a 4:1 extract ratio does not guarantee either polyphenols or L-theanine.
Green tea extract grades compared
| Grade | Specification basis | Primary buyer check |
|---|---|---|
| 20% tea polyphenols | Moderate standardized polyphenol level | Assay method, actual result and carrier |
| 50% tea polyphenols | Higher standardized polyphenol level | Marker profile, solubility and sensory impact |
| 98% tea polyphenols | Highly concentrated polyphenol grade | Method, composition, caffeine requirement and dosage calculation |
| 20% L-theanine | Standardized to L-theanine rather than total polyphenols | L-theanine method, source and other declared constituents |
| 4:1 extract | Ratio-defined botanical extract | Ratio basis, solvent, carrier and identity |
Polyphenol percentage is not an extract ratio
A percentage grade sets an acceptance criterion for a measured group of compounds. A 4:1 ratio describes the relationship between starting material and extract under a supplier’s process definition. Buyers should not convert a ratio into an assumed polyphenol value or compare prices until the specifications have been aligned.
How to choose between 20%, 50% and 98% polyphenols
Begin with the amount of polyphenols required in the finished formula and calculate the input needed for each grade. Then compare composition, carrier, moisture, solubility or dispersibility, color, taste, bulk density and cost per unit of declared marker. A higher assay can reduce inclusion weight, but it may change handling, sensory performance and total formulation cost.
When a 20% L-theanine grade is appropriate
Select an L-theanine-standardized grade when the specification requires a defined L-theanine input. Confirm the analytical method, actual batch result, source declaration and any limits for other constituents that matter to the application. A tea-polyphenol grade should not be treated as an equivalent substitute.
Caffeine and constituent profile
Do not assume caffeine content from the product name alone. If a caffeine limit or decaffeinated requirement applies, state the numerical limit and method in the RFQ. Where catechin or EGCG composition matters, request those criteria separately rather than inferring them from total tea polyphenols.
COA and sample qualification checklist
- Botanical name, leaf part and extract grade match the specification.
- Actual marker result, method and reporting basis are stated.
- Extraction solvent, carrier and excipients are disclosed.
- Caffeine, catechin or EGCG limits are specified when required.
- Moisture, particle size, density and solubility fit the process.
- Heavy metals, pesticides, residual solvents and microbiology match the target market.
- Sample label and COA share the same batch number.
Use the botanical extract COA checklist to review the document set and see LongBio’s quality and certification information for supplier qualification context.
RFQ information that prevents mismatched quotations
State the exact marker and percentage, intended application, target market, trial and annual quantity, caffeine requirement, preferred carrier, physical-property needs, contaminant limits, packaging and required documents. If the correct grade is uncertain, send the formula objective through the contact page.
Frequently asked questions
Is 98% tea polyphenols always the best grade?
No. The suitable grade depends on marker input, formulation behavior, sensory limits, documentation and total cost.
Does 4:1 mean 40% polyphenols?
No. An extract ratio does not establish a polyphenol percentage.
Does total tea polyphenols specify EGCG?
No. Request an EGCG criterion separately when it is required.
Should caffeine be included in the RFQ?
Yes, whenever the application, customer or market requires a defined caffeine limit.