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加熱処理を要する野菜, 5種類を用いて, 各貯蔵条件下のビタミンC含量の変化を検討した。その結果, 生のまま貯蔵した場合, カリフラワー, さやいんげん, 芽キャベツは冷蔵, 室温貯蔵ともに, 総ビタミンCの減少は殆ど認められず, 還元型, 酸化型の割合の変化もみられなかった。ブロッコリー, 春菊については, いずれの場合もビタミンCの減少傾向が認められ, とくにブロッコリーは室温貯蔵におけるビタミンCの減少は顕著であった。加熱処理をして冷蔵した場合は, いずれの野菜も総ビタミンCの減少傾向は生の場合とほぼ同様であったが, 還元型と酸化型の割合において, 酸化型が増加する傾向にあり, とくにカリフラワー, 芽キャベツにおいてその傾向が大であり, 他のものについては貯蔵期間が長くなった場合に, その傾向が認められた。生で冷蔵したものを使用前にゆでた場合には, 還元型と酸化型の割合における変化は殆ど認められず, これらの野菜類については, 生で冷蔵し使用直前に加熱処理をする方法が望ましいことが明らかとなった。また, 生食する野菜, 5種類を用いて冷蔵および室温貯蔵を行ない, 同様にビタミンC含量の変化を検討したが, これらの野菜類のビタミンCは比較的安定で, トマト, きゅうり, キャベツにおいては, 冷蔵, 室温貯蔵ともに殆ど変化は認められなかった。また還元型, 酸化型の割合も変化しなかった。ピーマンは冷蔵の場合はビタミンCの減少は殆ど認められなかったが, 室温貯蔵の場合, わずかに減少の傾向を示した。大根については冷蔵, 室温貯蔵ともにわずかながら減少傾向を示し, 5日目には酸化型が増加する傾向が認められた。トマトはむしろ貯蔵中に総ビタミンCが増加する傾向

Changes of Vitamin C of vegetables stored under the several conditions were investigated. The vegetables employed in this experiments were cauliflower, Italian broccoli, garland chrysanthemum, kidney beans with pod (immature), Brussels sprouts, tomato, cucumber, sweetpepper, Japanese radish root and cabbage. The total contents of Vitamin C of cauliflower, kidney beans with pod (immature) and Brussesl sprouts, when they were stored in raw, did not decrease both under the refrigerated storage and the storage in room temperature for 5 days, although those of Italian broccoli and garland chrysanthemum decreased gradually during the storage. On the other hand, when these vegetables were stored in refrigerator after boiled, the rate of the oxidized type to the reduced type of Vitamin C showed a tendency to increase. In cauliflower and Brussels sprouts, especially, increased the oxidized type of Vitamin C. However, change of the rate of the oxidized type to the reduced type was not observed, when the vegetables stored in refrigerator in raw were boiled before employment. In the case of tomato, cucumber and cabbage, changes of Vitamin C were not almost observed both under the refrigerated storage and the storage in room temperature in raw for 5 days. It seems that Vitamin C of these vegetables were relatively stable. Vitamin C of sweetpepper was decreased a little under the storage in room temperature, although it was not decreased under the refrigerated storage. Vitamin C of Japanese radish root showed a tendency to decrease under both conditions and the rate of the oxidized type to the reduced type of Vitamic C increased slightly at the fifth day. Tomato was observed to get ripe during the storage, and Vitamic C had a tendency to increase.

source:Bulletin of the Faculty of Education, Chiba University