不同浸泡条件对石榴茶营养性及抗氧化性的影响_食品科学与工程.rar

摘要:本课题主要是以石榴茶为原料，以普通红茶为对照，考察在不同的浸泡温度70℃、80℃、90℃、100℃，不同浸泡时间5min、15min、25min、35min、45min、55min以及不同浸泡料液比1:25、1:50、1:75、1:100，以石榴茶的透光率、茶多酚含量以及清除羟基自由基的能力为指标，以其品质的变化确定最佳浸泡条件。并在最佳浸泡条件下测得石榴茶中游离氨基酸、类黄酮、可溶性糖、Vc、叶绿素的含量以及其还原力、TBA抑制率、超氧阴离子的清除率。结果表明：浸泡时间为15min，浸泡温度80℃，料液比为1:50时为最佳浸泡条件。在此条件下，石榴茶的透光率为71.6%，羟基自由基清除率为47.1%，茶多酚含量为0.707mg/g，游离氨基酸含量为0.597μg/mL，可溶性糖含量为106.82μg/mL，类黄酮的含量为0.197μg/mL，Vc含量为18.00μg/mL，叶绿素的总浓度为39.83mg/L，抗氧化性物质TBA抑制率为10.6%，超氧阴离子清除率为54.47%。在最佳浸泡条件下游离氨基酸含量比对照（普通红茶）增加了0.042μg/mL，可溶性糖含量增加了0.34μg/mL，类黄酮的含量增加了0.12μg/mL，Vc含量增加了5.5μg/mL，叶绿素的总浓度增加了13.3mg/L，抗氧化性物质TBA抑制率提高了2.84%，超氧阴离子清除率提高了16.62%。

关键词: 石榴茶；浸泡条件；营养成分；抗氧化性

Abstract:The main subject is based on the pomegranate tea as raw materials, choosing the ordinary black tea as the contrast, according to the changes in the quality of the pomegranate tea, the light transmittance of the pomegranate tea ,the content of tea polyphenols as well as the ability to clear the hydroxyl radical as the indicators to determine its best soaking conditions under different soaking temperature of 70℃, 80℃, 90℃, 100℃, different soaking time of 5min, 15min, 25min, 35min, 45min, 55min and different ratioes of solid-liquid 1:25, 1:50, 1:75, 1:100. Optimal soaking conditions measured pomegranate tea free amino acids, flavonoids, soluble sugar, Vc, chlorophyll content, and reducing power, TBA suppression rate, clearance rate of superoxide anion. The results show that: the soaking time of 15min, a soak temperature 80℃, solid-liquid ratio of 1:50 is the best soaking conditions. In this condition, the the pomegranate tea light transmission rate of 71.6%, hydroxyl radical scavenging rate was 47.1%, polyphenol content of 0.707mg/g, free amino acids 0.597μg/mL soluble sugar content 106.82μg/mL; flavonoids was 0.197μg/mL; Vc content 18.00μg/mL; the total concentration of chlorophyll was 39.83mg/L; the antioxidative substances TBA inhibition rate was 10.6%; superoxide anion scavenging rate was 54.47%. Free amino acids in the optimal soaking conditions than in the control(black tea) 0.042μg/mL soluble sugar content 0.34μg/mL, flavonoids increased 0.12μg/mL, Vc content increased 5.5 ug/mL, the total concentration of chlorophyll increased 13.3mg/ L, the antioxidation substance TBA inhibition rate increase of 2.84%, 16.62% increase in superoxide anion scavenging rate.

Keywords  Pomegranate tea  Soaking conditions  Nutrient Composition  Anti-oxidation