張卜升 李鐵柱 成妮妮
摘要:采用分光光度法、高效液相色譜(HPLC)法分析茶樣中的酚類(lèi)物質(zhì),通過(guò)氣相色譜-質(zhì)譜聯(lián)用(GC-MS)法分析茶樣中的揮發(fā)性成分,并以龍井、正山小種和鐵觀音茶葉作為石榴葉綠茶、紅茶和烏龍茶的對(duì)照。結(jié)果表明,石榴葉綠茶、紅茶和烏龍茶總酚含量分別為156.73、137.44和123.10 mg/g,均高于相應(yīng)的對(duì)照;各茶樣鞣花酸含量相差不大,均保持在2.11~2.39 mg/g;石榴綠茶、紅茶和烏龍茶的兒茶素含量分別為6.02、1.49和7.01 mg/g,均低于相應(yīng)對(duì)照,其中石榴葉紅茶的兒茶素含量最低僅為正山小種的26%;從石榴葉綠茶、紅茶和烏龍茶中分別鑒定出26、33和34種揮發(fā)性成分,獨(dú)有成分分別為3、5和8種。表明不同加工工藝對(duì)石榴葉茶的酚類(lèi)物質(zhì)含量及揮發(fā)性成分影響顯著,與綠茶相比石榴葉紅茶及烏龍茶的總酚含量均顯著減少,澀味減輕;石榴葉紅茶和烏龍茶中揮發(fā)性成分種類(lèi)更多,并具有更豐富的特有成分,從而形成了不同工藝的特有香氣類(lèi)型。
關(guān)鍵詞:石榴葉茶;酚類(lèi)物質(zhì);揮發(fā)性成分;加工工藝
中圖分類(lèi)號(hào):S571.1? ? ? ? ?文獻(xiàn)標(biāo)識(shí)碼:A
文章編號(hào):0439-8114(2019)07-0099-06
Abstract: The contents of phenolic compounds in the samples were measured using spectrophotometry and high performance liquid chromatography(HPLC) method, and the volatile components was analyzed by gas chromatography-mass spectrometry (GC-MS) method, in addition Longjing, Zhengshanxiaozhong and Tieguanyin tea as control of green tea, red tea and oolong tea. The results showed that total phenolic contents of pomegranate green tea, red tea and oolong tea are 156.73, 137.44 and 123.1 mg/g respectively, and higher than those of the control; the ellagic acid contents of samples have little difference, maintaining at 2.11~2.39 mg/g; the catechin contents of them are 6.02, 1.49 and 7.01 mg/g respectively, and lower than the corresponding control, especially that of the red tea is the lowest only 26% of Zhengshanxiaozhong. 26, 33 and 34 kinds of volatile components were identified from pomegranate green tea, red tea and oolong tea, and with 3, 5 and 8 kinds of unique ingredients respectively. It is suggested that the effects of different processing technology on the contents of phenolic compounds and volatile components of pomegranate leaf tea are significant, comparing with pomegranate green tea, total phenolic content of red tea and oolong tea reduced significantly and the tea astringency decreased. The volatile component species of pomegranate red tea and oolong tea are more than green tea, and with more rich special elements, thus forming unique aroma types of different technology.
Key words: pomegranate leaf tea; phenolic substances; volatile components; processing technology
石榴(Punica granatum L.)原產(chǎn)中西亞地區(qū),古人譽(yù)之“天下之奇樹(shù),果中之極品”。《圖經(jīng)本草》載:“榴葉者,治咽喉燥渴,止下痢漏精,消食祛火”[1]。石榴葉中含有豐富的生物活性物質(zhì),包括酚類(lèi)、黃酮及三萜類(lèi)等[2-4],尤以多酚含量最高[5,6]。研究表明,多酚具有抗氧化[7,8]、抗衰老、抗癌防癌[9,10]、抗菌、潤(rùn)膚美容、降血壓和預(yù)防心腦血管疾病[11]等功效。經(jīng)現(xiàn)代科學(xué)鑒定,石榴葉含β-谷甾醇、槲皮素、石榴酸等[12],并含多種揮發(fā)油及微量元素,具有助消化、健胃怡神、促進(jìn)代謝等功效[13],對(duì)人體起到一定的保健功能。山東省棗莊市嶧城區(qū)作為中國(guó)著名的“中國(guó)石榴之鄉(xiāng)”,石榴栽培歷史悠久,栽培面積大,品種多樣,有巨大的開(kāi)發(fā)潛力。石榴葉可以加工成茶葉供飲用,石榴綠茶與紅茶中酚類(lèi)物質(zhì)及抗氧化活性存在較大差別[14],但對(duì)不同工藝加工的石榴葉茶酚類(lèi)物質(zhì)及揮發(fā)性成分的比較研究鮮有報(bào)道。本試驗(yàn)以傳統(tǒng)的龍井、正山小種和鐵觀音3種茶葉為對(duì)照,探索綠茶、紅茶及烏龍茶3種加工工藝對(duì)石榴葉茶中酚類(lèi)物質(zhì)及揮發(fā)性成分的影響,為篩選石榴葉茶適宜的加工工藝提供依據(jù),為科學(xué)開(kāi)發(fā)石榴葉資源提供參考。