Adding citrus juices or vitamin C to green tea may raise its antioxidant goodness, a new study suggests.

    The antioxidants in question are called catechins, believed to be responsible for some of green tea's reported health benefits, such as reducing the risk of cancer, heart attack and stroke.

    "Although these results are preliminary, I think it's encouraging that a big part of the puzzle comes down to simple chemistry," lead author Mario Ferruzzi, assistant professor of food science at Purdue University in West Lafayette, Ind., said in a prepared statement.

    Using a laboratory model that simulates digestion in the stomach and small intestine, Ferruzzi tested green tea with a number of additives, including juices and creamers. 

    He found that citrus juice increased recoverable (absorbable) catechin levels by more than five times, while vitamin C (ascorbic acid) boosted recoverable levels of the two most abundant catechins by six and 13 times.

    The findings were published in the journal Molecular Nutrition and Food Research.

    Citrus juices and vitamin C may interact with catechins to prevent degradation in the intestines, Ferruzzi said.

    "If you want more out of your green tea, add some citrus juices to your cup after brewing or pick a ready-to-drink product formulated with ascorbic acid," he suggested.

    Ferruzzi is currently conducting a study examining whether citrus juices and vitamin C increase catechin absorption in lab animals.

    一項新的研究表明，在綠茶中加入柑橘類果汁或維生素C可提高其抗氧化作用。

    被研究的抗氧化劑名為兒茶素，被認為是綠茶中對身體有益的物質，如減少患癌癥、心臟病和中風的風險。 

    "雖然這些成果都是初步的，但大部份的疑惑都被簡單的化學作用所解開，我認為這很令人鼓舞，"此研究的主筆人馬里奧費魯齊，執教于印第安納州西拉斐特市普渡大學的助理教授在一份準備好的聲明中說。 

    費魯齊用實驗模型來模擬胃和小腸消化功能，向綠茶中放一些添加劑如果汁和奶蓋來測試綠茶。

    他發現，柑橘汁將可恢復（可吸收的）兒茶素水平提高了5倍還多，同時維生素C（抗壞血酸）將其中兩種含量最多的兒茶素中的可恢復水平提高了6倍和13倍。

    調查結果刊登在雜志分子營養與食品研究上。

    柑橘類果汁和維生素C也可與兒茶素相互作用以防止腸子的退化，費魯齊說。 

    他建議，"如果你想從綠茶獲得更多好處，，在泡好的茶中加上一些柑橘類果汁，或挑選一種加抗壞血酸的即飲產品" 。

    費魯齊目前正在從事一項研究，在實驗室動物身上研究柑橘類果汁和維生素C是否能增加兒茶素的吸收水平。