We proposed a new method to average time serieses, and analyse growth index of the first tea crop (rate of banjhi shoot, bud weight, bud length, leaf number). Traditional averaging, which is adopted in annual crop report, is a simple successive averaging of numbers of data at the same calendar day. A new method proposed here is done as follows. Data of an index of each year was fitted to a logistic curve. Time value of all the inflections of an index were averaged, and phase of all curve was shifted to the averaged inflection value. Function value from daily calculation of each curves was fitted again to a logistic curve with weighing by data number. We can use the resulted curves for prediction of growth and estimation of a growth index from another.

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The differeces on roasted green tea (Hoji-Cha) flavor were compared between the orthodox roasting (0) by pan-direct-heating and the combined roasting (C) with pan-direct-heating and far-infrared rav radiation.
On the O-roasting, Hoji-cha was over-heated on pan surface fixed at high temperature and strong roasting aroma was produced. On the C-roasting with two heating sources, the temperature of pan surface was fixed lower than that of the 0-roasting. And by combined heat energis of the far-infrared ray radiation and direct-pan-heating teas were roasted uniformly. Then, as the over-heating of tea was averted, the C-roasting teas showed milder and more fragrant flavor than the O-roasting teas.

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The bright green colored green tea cultivar, 'Sakimidori' released in Miyazaki Prefecture in 1997, was compared to 'Yabukita' on the bases of chlorophyll(Chl) and pheophytin(Phy) contents in their crude teas.
Chl(a + a') and Chl(b + b') were about 1.3-1.5 times higher in 'Sakimidori' than 'Yabukita' in the first and second crops. Chl(a+a') contents in the first crop were about 1.4-1.7 times higher than those in the second crop, while Chl (b + b') contents in the first crop were slightly higher than those in the second crop. As steaming times became longer, Chl(a+a') contents decreased significantly, while Chl(b + b') contents decreased slightly. 'Sakimidori' and 'Yabukita' contained similar amounts of Phy(a+a') and Phy(b+ b') in the first crop ; these two components were slightly higher in 'Sakimidori' in the second crop. Both 'Sakimidori' and 'Yabukita' contained markedly higher Phy(a+a') in the first crop as compared to the second crop. Phy(a+a') and Phy(b+b') increased with increasing steaming times. The conversion rate of Chl into Phy in 'Sakimidori' was less than that in 'Yabukita' both in the first and second crops. In both 'Sakimidori' and 'Yabukita', this conversion rate in the first crop was lower than that in the second crop. The conversion rate increased with increasing steaming times.
The higher level of Chl and the lower conversion rate of Chl into Phy in 'Sakimidori' reflect the bright green color of its crude tea.

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Oxalic acid is felt uncomfortable to the tongue. The contents of oxalic acid were more than 1% in Gyokuro, around 0.9% in Sencha, and less amounts in Bancha and Houjicha. The contents of oxalic acid were not decreased in the process of roasting. Oxalic acid in tea leaves was easily extracted into water even in low temperatures around 40°C. The intensity of the taste of oxalic acid was not always correlated to the concentrations of oxalic acid in tea infusions, and it was suggested that other ions, such as phosphate, had influenced at the taste of oxalic acid:

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We chemically synthesized several (+)-catechin glycosides which included (+)-catechin 3-O-β-D-glucopyranoside, -3-O-α-D-mannopyranoside, -3-O-β-D-xylopyranoside, -3-β-β- D -galactopyranoside, and -3-O-β-maltoside. The yields of the glycosides were improved by using silver perchlorate and silver trifluoromethanesulfonate as condensing agents. The use of these condensing agents shortened the reaction time also.
The inhibitory activities of these glycosides were examined against several enzymes including tyrosinase, xanthine oxidase, β-galactosidase, hyaluronidase and peroxidase. The glycosides highly inhibited tyrosinase activity and inhibited f3-galactosidase activity to a certain extent. On the other hand, inhibitory effects of the glycosides on hyaluronidase and peroxidase were rather lower than the lead compound, (+)-catechin.

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Canopy characteristics were investigated by the stratiform clipping method on Oct. 9th. 1998 in three tea (Camellia sinensis L.) bushes of which the second crop were plucked on Jun. 11, 15 and 19th in 1998. Autumn canopies were structured above the skiffing position of the last autumn in all tea bushes. The weight of branches, the weight of leaves, leaf area index, the number of apical buds and lateral buds concentrated in -4-0cm, 0-+6cm, 0-+6cm, -2-+4cm and -4-+2cm layers (0cm : the plucking position of the second crop, + : upper direction, - : under direction from the position), respectively. These values were higher as the second crop had been plucked later. A simulation of various autumn skiffing heights for these bushes concluded that a later plucking of the second crop induce more buds appeared on the canopy surface keeping enough leaf layer before the next crop.

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New green tea cultivar ‘Musashikaori’ has been bred at the Saitama Tea Experiment Station. The clone was selected from seedlings crossed between ‘Yabukita’ (_??_) and ‘27F₁-73’ (_??_) in 1967. Local adaptability, tolerance to bark split frost injury, and Blister blight were tested at 17 prefectural tea experiment stations from 1990 to 1996. It was registered as ‘Norin No.46’ and named ‘Musashikaori’ in 1997. The characteristics of the cultivar are as follows ;
The shape of plant is spread type, and the growth is vigorous. The size of mature leaves are smaller than those of ‘Yabukita’. Young leaves are lustrous green and soft. The yield of 1st or 2nd crop is higher than that of ‘Yabukita’. The flushing time of the first crop of this cultivar in Saitama, is 1 day later than that of ‘Yabukita’, and the plucking time is 2 days later. At the other experiment stations the flushing time is 2 to 7 days later, and the plucking time is 2 to 4 days later than ‘Yabukita’. Rooting ability of nursery plants are high and taking roots after planting is good. ‘Musashikaori’ is resistance to cold drought and bark split frost injury. The level of resistance to freezing injury is almost the same as ‘Yabukita’. The damage to Anthracnose is less than that of ‘Yabukita’. However, the level of resistance to Blister blight is almost the same as ‘Yabukita’. Tea quality is good both in appearance and quality of liquor. ‘Musashikaori’ is suitable for northern tea producing areas, and cool semi-mountainous areas.

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