Comparison of the Chemical Components of Powdered Green Tea Sold in the US

Abstract

The international market for green tea is growing. Samples of twenty-five powdered green teas were collected from the market in the United States, and their chemical components were compared. Their prices varied widely, from $4.3 to $160 per 100 g. The higher-priced teas were labeled as "matcha" and are used in the traditional Japanese tea ceremony. They showed a higher content of chlorophyll and of free amino acids (theanine and arginine) than the less expensive teas. They also showed a lower content of epigallocatechin as well as a lower conversion percentage of chlorophyll to pheophytin than those of lower prices. Matcha is traditionally produced in Japan and considered one of the country's most precious teas. In spite of the large differences in chemical composition compared with the highly priced powdered green teas (ceremonial-grade matcha), the cheaper teas are also labeled as "matcha" in the US market. It is, therefore, necessary to come up with an international definition of matcha to resolve the confusion.

Stress-reducing effect of cookies containing matcha green tea: essential ratio among theanine, arginine, caffeine and epigallocatechin gallate

“…However, inexpensive matcha of which theanine content is low and catechins are high is often used for processing. Low-grade green teas with a low amino acid content are also sold as "matcha" in the US [32], indicating that a quality check of matcha is needed not only in the US but also in other countries. Especially, a reference value of matcha components is required to vouch for the stress-reducing effect of matcha.…”

Stress-Reducing Function of Matcha Green Tea in Animal Experiments and Clinical Trials

“…This indicates that greater attention is needed to evaluate the mental function of matcha. Although the number of people drinking green tea as a health beverage is increasing in many countries, low-grade green teas with low amino acid contents are also sold as “matcha” [ 32 ]. Many matcha marketed overseas had low amino acids contents ( Figure 5 , Table S2 ).…”

Effects of stem removal on physicochemical properties and sensory quality of tencha beverages (Camellia sinensis; Chuanxiaoye)

“…The concentration of EGC in LOT was lower than that in LST during similar plucking periods. Studies have reported that EGC content was lower in high‐priced teas than in low‐priced teas (Chen et al., 2003; Horie et al., 2018), supporting the assumption that t LOT is of higher‐quality than LST. ECG concentration did not differ significantly between different between different chuanxiaoye samples ( p > 0.05) other than for 3‐LST, which may be because young tea leaves are richer in ECG than mature leaves (Chen et al., 2003).…”

“…High‐quality matcha generally has a green color, mellow taste, and nutritional value, which are closely related to the component types and concentrations. High‐quality matcha usually contains contents of high amino acids and chlorophylls but low catechins (Horie, Ema, Nishikawa, & Nakamura, 2018). Therefore, a high phenol ammonia concentration and low greenness in matcha are suboptimal.…”