Green tea drink

Commercial extracts of green tea are marketed for the prevention of heart disease and of cancer because of the powerful antioxidant and free radical scavenging properties of the polyphenols. In the case of heart disease it is known that in rats green tea extracts decrease plasma cholesterol and lipid levels. Epidemiological studies in Japan suggest a relationship between lower LDL-cholesterol and increased green tea drinking. 

The effect of the retorting process and UHT sterilization on the flavor of green tea drink is shown in figure 17.3. The intensity of off-flavor (potato-like, floral, sweet, heavy, spicy) increased during retorting and sterilization, and the characteristic green... 

FIGURE 17.3 Odor intensity and odor description of green tea drinks before and after heating process. Retorting process 121°C, 10 minutes. UHT sterilization 134°C, 30 seconds. Odor intensity of nonheated green tea drink (control) 3. pH 6.2 (control), 5.6 (after retorting process), 6.1 (after UHT sterilization). 

FIGURE 17.4 FD (flavor dilution) factors of flavor components of green tea drinks due to the heating process. 

Figure 17.8 shows the change in the flavor components of green tea drinks induced by the retorting process. These data are obtained by the calculation of the GC area... 

FIGURE 17.7 Potent flavor components of green tea drink identified by AEDA. Nonretorting process. FD factor of the flavor components greater than 500. 

FIGURE 17.8 Relative peak area of flavor components in green tea drinks before and after retorting process. Retorting process 120°C, 8 minutes. pH 6.0 (control). 

FIGURE 17.9 Structures of increased flavor components of green tea drink after the heating process among flavor components shown in figure 17.8. 

Kumazawa, K. and Masuda, H. 2005. Effect of heat processing conditions on the flavor change of green tea drinks. Nippon Shokuhin Kagaku Kogaku Kaishi 52 34-40. 

Tea can be consumed directly either by brewing loose leaves or tea bags or in a ready-to-drink form. In addition, extracts of tea (primarily green tea) may be prepared in a variety of physical forms in order to cover most application requirements. 

JANKUN J, SELMAN s H, swiERCZ R and SKRZYPCZAK-JANKUN E (1997) Why drinking green tea could prevent cancer . Nature, 387, 561. 

NAKACHi K, SUEMASU K, suGA K, TAKEO T, iMAi K and HIGASHI Y (1998) Influence of drinking green tea on breast cancer malignancy amony Japanese patients , Jpn J Cancer Res, 89, 254-61. 

Flavonoids are found in fruits, vegetables, seeds, and flowers, as well as in some drinks, such as beer, wine, black and green teas, and soy beverages. Consequently, these kind of compounds are consumed in a normal diet, although they can also be consumed as supplements. 

In another cohort study of a Japanese population, researcher surveyed more than 8000 individuals over 40 years of age on their living habits, including daily consumption of green tea. Results found a negative association between green tea consumption and cancer incidence, especially among females drinking more than 10 cups per day [212]. 

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