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利用响应面法对超声波-微波协同提取黑果枸杞叶总黄酮的工艺进行优化,在单因素试验基础上,以微波功率、液料比、提取时间、乙醇浓度为主要因素,总黄酮提取率为响应值,通过响应面分析法进行四因素三水平BoxBehnken试验对提取条件进行优化。结果显示,各因素对黑果枸杞叶总黄酮提取率相对影响程度为:液料比乙醇浓度提取时间微波功率。且液料比18.9∶1(mL/g),乙醇浓度69%,提取时间9.9 min,微波功率175 W为最佳提取条件,此时黑果枸杞叶总黄酮提取率为(0.997±0.015)%。理论预测值为1.01%,结果与预测值基本符合,证明该模型有效,工艺稳定可行。 相似文献
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超声波辅助提取会理石榴皮中总黄酮的工艺研究 总被引:1,自引:0,他引:1
《中国食品添加剂》2019,(9):106-110
以会理石榴皮为原材料,采用超声波辅助提取法,以料液比、提取液浓度、超声温度、超声时间作为影响因素,通过单因素和正交试验确定会理石榴皮总黄酮的最佳提取工艺。最佳的工条件为:乙醇浓度70%、料液比1∶50、超声时间90min、超声温度70℃、超声功率300W,石榴皮中总黄酮的提取率可达到6.82%。乙醇的浓度对提取率的影响较大,实际生产中应加以控制。 相似文献
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采用响应面法对超声辅助提取桂皮总黄酮进行研究。在单因素基础上,采用Box-Benhnken中心组合试验设计和响应面分析法考察液料比、乙醇浓度、超声功率、提取时间对桂皮总黄酮提取率的影响。结果表明:桂皮总黄酮最佳提取条件为液料比21∶1,乙醇浓度71%,超声功率452 W,提取时间63min。在此条件下桂皮总黄酮提取率预测值为5.60%,验证值为5.61%,构建的模型方程能够较好地预测试验结果。 相似文献
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黑蒜发酵过程中总酚含量变化及提取工艺的研究 总被引:1,自引:0,他引:1
《食品科技》2016,(2)
以市售大蒜为原料进行黑蒜发酵,测定2组发酵工艺过程蒜样中总酚含量的变化,同时探究乙醇浓度、超声功率、超声时间、料液比对黑蒜中总酚提取率的影响,采用L9(34)正交实验设计对黑蒜总酚超声波辅助提取条件进行优化。研究结果表明,蒜样中总酚含量变化与发酵温度及变温周期有密切的关系,4个单因素影响总酚提取率大小顺序为:料液比超声时间乙醇浓度超声功率,确定了最佳的总酚提取工艺:乙醇浓度30%,超声功率60%,超声时间为40 min,料液比为1:40,此条件下总酚提取量率为20.88 mg/g。 相似文献
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我一直固执地认为,爱喝茶的人要么外表斯文温文尔雅、要么举止文雅仙风道骨。在见到一品古道范承胜先生时,我的"固执"得以应验,这次见吴秘书长,我很庆幸,我的"固执"又一次"巧合"地吻上了,看来我应该继续"固执"下去……吴锡端,中国茶叶流通协会秘书长,他有着典型的茶人脸庞,一看就是位知者、智者;他是嗅着茶香长大的,与茶的缘分是天定的。要说他的茶缘,且随我一同进入本期的茶奇人物吧! 相似文献
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Jin Ze Xu Lai Kwok Leung Yu Huang Zhen‐Yu Chen 《Journal of the science of food and agriculture》2003,83(15):1617-1621
The present study was carried out to quantify green tea epicatechin (GTE) derivatives and to investigate the origin of epicatechin epimers present in 18 selected canned or bottled tea drinks. The major GTEs present in tea are (?)‐epigallocatechin gallate (EGCG), (?)‐epigallocatechin (EGC), (?)‐epicatechin gallate (ECG) and (?)‐epicatechin (EC). HPLC analysis showed that the content of total GTEs was lower (16.4–268.3 mg l?1) in the canned and bottled tea drinks than in tea traditionally prepared as a beverage in a cup or teapot (3–5 g l?1). The major finding was that they contained higher levels of epicatechin epimers, namely (?)‐gallocatechin gallate (GCG), (?)‐gallocatechin (GC), catechin gallate (CG) and (?)‐catechin (C), than of GTEs, ranging from 7.6 to 331.8 mg l?1. To investigate the origin of these epimers, GTEs were extracted from longjing green tea and autoclaved at various temperatures for 10–60 min. It was found that at least 50% of GTEs were epimerised to their corresponding epimers when autoclaved at 120 °C for 20 min. It is concluded that epicatechin epimers in tea drinks are not originally present in green tea leaf but are instead derived from thermal conversion of GTEs. Copyright © 2003 Society of Chemical Industry 相似文献
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The polyphenol compositions of green tea (GT) and black tea (BT) are very different due to post-harvest processing. GT contains higher concentrations of monomeric polyphenols, which affect numerous intracellular signaling pathways involved in prostate cancer (CaP) development. BT polymers, on the other hand, are poorly absorbed and are converted to phenolic acids by the colonic microflora. Therefore, after consumption of GT, higher concentrations of polyphenols are found in the circulation, whereas after BT consumption the phenolic acid levels in the circulation are higher. The majority of in vitro cell culture, in vivo animal, and clinical intervention studies examine the effects of extracts of GT or purified (-)-epigallocatechin-3-gallate (EGCG) on prostate carcinogenesis. These studies provide strong evidence supporting a chemopreventive effect of GT, but results from epidemiological studies of GT consumption are mixed. While the evidence for a chemopreventive effect of BT is much weaker than the body of evidence with regard to GT, there are several animal BT intervention studies demonstrating inhibition of CaP growth. This article will review in detail the available epidemiological and human clinical studies, as well as animal and basic mechanistic studies on GT and BT supporting a chemopreventive role in CaP. 相似文献
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目的建立一种普洱茶中茶多糖的提取工艺。方法以普洱茶为材料,采用水提醇沉法,研究了浸提温度、浸提时间、浸提次数、乙醇浓度4个因素对普洱茶中茶多糖提取率的影响,并通过正交实验确定茶多糖的最佳提取工艺。且用此提取工艺测定市售不同级别普洱茶中茶多糖含量。结果普洱茶中茶多糖的最佳提取工艺为:浸提温度90℃,浸提时间40 min,浸提次数3次,乙醇浓度80%。该提取工艺重复性好,吸光度与葡萄糖含量呈良好的线性关系(n=5),线性范围0.02~0.10 mg/L(r2=0.9999)。实验也发现,普洱茶的嫩度越低,茶多糖的含量越高。结论本方法简便、快捷、重复性好,可作为茶叶多糖原材料和产品质量控制的方法。 相似文献
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刘智钧 《食品安全质量检测学报》2020,11(1):8-12
中国既是茶的原产地,也是茶的生产与消费大国,每年由于茶饮料及茶叶深加工产生大量的茶渣,仅仅以简单地丢弃处理而没有被高值化综合利用,既给环境带来了巨大的压力也造成了资源的浪费。茶渣中含有10%至16%粗纤维以及少量的络合态色素、矿物质、氨基酸、茶多酚、咖啡碱等,可以被多种形式地精深加工利用。本文综述了茶渣作为主要配料在作菌类的培养基、动物饲料的添加剂、植物的土壤肥料等方面的应用,以期为茶与茶渣的研究与利用提供参考。 相似文献
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《食品工业科技》2015,(5)
以自制黑茶为研究对象,分别采用超临界CO2萃取法、醇水浸提法及醇水浸提-超临界CO2联合萃取法对茶样中的茶多酚进行提取,用正交实验法优化了提取条件,以没食子酸为标准品,在765nm处用紫外可见分光光度法检测产品中茶多酚的含量,计算了茶多酚的得率及萃取样中产品的纯度,并对三种产品的DPPH·清除率进行了比较。结果表明:3种方法中醇水-超临界CO2联合萃取法的得率和纯度最高。联合浸提最优条件为:先用乙醇浓度80%,料液比1∶10g/m L,60℃下浸提2.0h,然后25MPa,50℃下超临界CO2萃取时间2h。茶多酚的得率为6.36%±0.81%,产品纯度为:41.22%±3.19%。产品对DPPH·的清除率为90.64%±0.0187%。该方法绿色环保,未添加任何有害溶剂,为黑茶饮品的进一步研究开发提供参考。 相似文献