Quality assurance of tea leaf and its products using selected major chemical
markers

Camellia sinensis or locally called the tea plant is one of the important food crops in
Malaysia besides other popular crops such as coffee and cocoa. Since the earliest
generations, tea has become one of the most popular beverages consumed globally. The
tea drinks popularity has been inherited by current generations together with traditional
knowledge of its benefits to human health. Recently, many types of tea products available
in local markets. In order to achieve the expected quality, the quality assurance of the
products must be in place. In this study, analysis method for detection and determination
of the selected major chemical markers which include catechin, epicatechin, caffeine,
theanine and theaflavin has been developed via High-Performance Liquid
Chromatography (HPLC). Evaluation of the tea products in the local market showed
variability in the level of chemical markers content. The content of catechin, epicatechin,
caffeine, theaflavin and theanine varies from 2.7-14.9, 2.7 - 30.3, 3.2 - 43.6, 0.28 -15.5,
29.1-57.7 mg/g, respectively. Quality assurance monitoring based on chemical markers is
crucial in order to produce high-quality tea-based products. The main advantage of this
developed method is all the targeted constituents could be detected within a single running
experiment. These could speed up analysis work and increase productivity. Consequently,
the scientific study data was also found to agree with the traditional claims. The previous
study demonstrated that tea leaves are rich with antioxidant properties especially catechin
which is reported to possess the powerful antioxidant capability, besides epicatechin,
caffeine, theanine and theaflavin.