Beverage Packed in Sealed Container

(1) Theanine Preparation 1

[0031] Theanine was prepared based on the technique disclosed as an embodiment in gazette of Japanese Patent No. 2139750. More specifically, 0.3 M glutamine and 1.5 M ethylamine were reacted in the presence of 0. 3U / ml glutaminase (refined from pseudomonas nitroreducens IFO 12694) at 30° C. for 22 hours in a boric acid buffer fluid (Na2B4O7—NaOH, pH 11) , whereby theanine was obtained. Reaction liquid was applied to Dowex 50×8 column chromatgraphy and Dowex 1×2 column chromatography thereby to be eluted by ethanol, whereby theanine was refined. As a result, 5 kg L-theanine was obtained. In the following description, the theanine prepared by the above-described preparing method will be referred to as “theanine 1.”

(2) Theanine Preparation 2

[0032] 1500 kg water was warmed up to 80° C., and 100 kg green tea leaves were added to the warmed water and stirrered for 30 minutes so that tea dregs were removed. Thereafter, filtration and concentrated refinement we...

(1) Preparation of Tea Beverage:

[0035] Extraction from 1 kg tea leaves of green tea was carried out in 10 liter hot water (60° C.) for 30 minutes and thereafter, solid-liquid separation was carried out by a filtration process, whereby 7 liter green tea extract was obtained.

[0036] Theanine 1, Theanine 2, quinic acid and tea extract powder containing quinic acid were blended together with blending quantities of the respective substances shown by TABLE 1 and put into a polyethylene terephthalate (PET) bottle aseptically after ultra high temperature (UHT) sterilization (sterilization at 135° C. for 3 seconds), whereby a beverage contained in a sealed container was prepared. Thus, 8 types of test beverages (1 to 8) and two types of comparative beverages (9 and 10; comparative example) were prepared.

TABLE 1ComparativeTest beveragebeverage12345678910Theanine 1 (mg)100100300300100300Theanine 2 (mg)5001000Quinic acid (mg)50100501005050Tea extract100010001000powder (mg)Green tea450450450...

Black Tea Beverage Contained in a Sealed Container

(1) Preparation of Black Tea Beverage:

[0052] Extraction from 1 kg tea leaves of black tea was carried out in 10 liter hot water (60° C.) for 30 minutes and thereafter, solid-liquid separation was carried out by a filtration process, whereby 7 liter black tea extract was obtained.

[0053] Theanine 1, Theanine 2, quinic acid and black tea extract powder containing quinic acid were blended together with blending quantities of the respective substances shown by TABLE 4 and put into a PET bottle aseptically after ultra high temperature (UHT) sterilization (sterilization at 135° C. for 3 seconds), whereby a beverage contained in a sealed container was prepared. Thus, 6 types of test beverages (11 to 16) and two types of comparative beverages (17 and 18; comparative example) were prepared.

[0054] Furthermore, contents of theanine and quinic acid in each beverage were analyzed in the same manner as in the embodiment 2.

TABLE 4ComparativeT...