Effects of γ-radiation on white tea volatiles

Tea is the second most widely consumed beverages in the world and is processed from two and a bud of Camellia sinensis (L.). Depending on the processing may give rise to four mainly teas (green, black, oolong and white tea). The white tea is the one that has recently awakened interest in scientific community due the fact that this tea has more antioxidant property and activity than green tea. A further industrialization and commercialization of these plants become a problem of public health. The presence of potentially toxigenic fungi can be found in these products, indicating a great potential for the presence of mycotoxins that can cause acute and chronic effects in different organs and systems of the human body. Ionizing radiation is one of the most effective means disinfecting dry food ingredients. This treatment can inhibit cellular life division, like microorganisms, promoting a molecular structural modification. The aim of this study was evaluate the effects of radiation on volatile formation in white tea. Samples were irradiated in room temperature at 60Co source Gammacell 220 (A.E.C. Ltda) at doses of 0, 5, 10, 15 and 20-kGy. The volatiles organic compound was extracted by hydrodistillation and the extract was separated and identified by gas chromatography-mass spectrometry (GC-MS) analysis. The results show that the quantities of volatiles formations are directly proportional to the increase of radiation dose. About 37.86% of the compounds were stable at all radiation doses and 47.53% of new compounds were identified after irradiation. (author)