Catechin dosage (as EGCG)

Epigallocatechin gallate (EGCG) is the principal catechin in green tea and one of the most studied natural polyphenols for its antioxidant, anti-inflammatory, and cell-protective effects. Its concentration is a major indicator of the quality and functional value of green tea extracts, nutraceutical ingredients, and wellness formulations.

EGCG testing is essential to ensure the conformity of plant-based raw materials, verify the stability of finished products, authenticate the origin of extracts, and support nutritional claims. Ingredient manufacturers, nutraceutical formulators, and dietary supplement brands rely on this analysis to standardize their products and secure their supply chains.

Analytical methods dedicated to EGCG

The analysis of catechins in the form of EGCG is generally performed by high-performance liquid chromatography (HPLC or UPLC), combined with UV detection at 280 nm or mass spectrometry (LC-MS/MS) for more precise identification. These methods allow the separation of EGCG from other polyphenols such as ECG, EGC, or EC, present in plant matrices.

Depending on the client's objectives, several analytical parameters can be evaluated:

• precise quantification of EGCG
• complete catechin profile
• possible presence of isomeric epicatechins
• assessment of oxidative degradation
• detection of adulteration or dilution

Mass spectrometry is particularly useful for complex matrices, low concentrations, or strict quality control requirements.

Matrices analyzed and use cases

EGCG testing is relevant to a wide range of applications:

• dry extracts of green tea or of botanical origin
• dietary supplements in capsules, tablets or powders
• functional drinks and concentrated infusions
• cosmetic formulations rich in antioxidants
• standardized technical or polyphenolic ingredients

into a complete analysis of polyphenols, just like the measurement of catechin , esculin , or volatile compounds when the study concerns a complex botanical extract.

Industrial applications and regulatory requirements

For manufacturers of natural products, the dosage of EGCG addresses several issues:

• ensuring compliance with international quality standards for green tea
• check the claimed concentration on nutraceutical products
• to ensure stability in liquid or solid formulations
• documenting quality, safety and marketing records
• detect common adulterations on the market (diluted extracts, partial substitution, oxidative polymerization)

In dietary supplements, this dosage can be correlated with other parameters such as total polyphenols , free amino acids , or chemical composition . For cosmetic extracts, it contributes to controlling antioxidant bioactivity.

Further analyses recommended

To obtain a complete profile of the extract or product being studied, YesWeLab recommends combining the EGCG dosage with:

• an overall measurement of polyphenols
• an analysis of specific flavonoids
• a characterization of volatile compounds (terpenes, aldehydes, phenols)
• an antioxidant stability study via the Total Antioxidant Status (TAS)
• an analysis of potential contaminants or residues
• pH measurement for liquid solutions

These analyses offer a comprehensive view enabling the optimization of formulations and the strengthening of nutritional or cosmetic arguments.

YesWeLab Expertise

Thanks to a network of partner laboratories specializing in chromatographic analysis and accredited according to ISO 17025 or COFRAC standards, YesWeLab guarantees the selection of the most suitable method, regardless of the matrix type, the level of precision required, or the regulatory requirements of the sector. Our scientific team provides personalized support, from defining the need to interpreting the results, taking into account technical, budgetary, and regulatory constraints.

Since 2020, more than 200 companies—laboratories, formulators, distributors, nutritionists, and research firms—have relied on YesWeLab to outsource and optimize their analytical strategy. Our platform centralizes requests, simplifies tracking, guarantees on-time delivery, and ensures the technical reliability of every analysis.