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11.
采用四种方法制备香草兰酊剂,通过反相高效液相色谱分析其中香兰素的含量和纯度,对各方法进行了讨论。  相似文献   
12.
本文利用95%乙醇和超临界CO2流体分别萃取香草兰豆荚,对萃取物的香气成分GC/MS分析,并用NIST107LIB、NIST21LIB数据库检索,分别鉴定出28种和31种化合物;用高效液相色谱测定萃取物中香兰素的含量。结果表明,两种萃取方法得到的香气物质其化学组成有较大差别。  相似文献   
13.
Green vanilla beans were subjected to the traditional curing process in Mexico. Odor-active potential from beans including 23 compounds was monitored through the analysis of both free and glucosidically bound volatiles. 8 of them were aliphatic aldehydes, acids, alcohol and ketone. 15 molecules were shikimate derivatives in which 13 were detected in glucosylated form. Some glucosides were efficiently hydrolyzed while some others partly or not at all after 90 days of curing. Moreover kinetics of hydrolysis of glucosides were not the same. A major part of glucovanillin was hydrolyzed at the first stages of curing while some other glucosides at the advanced stages. Data support hypothesis that hydrolysis of glucosides during curing is rather enzymatic origin than chemical one. Free shikimate derivatives or those liberated from glucosides are prone to chemical or enzymatic interconversions leading to a significant change in the aroma profile of cured vanilla.  相似文献   
14.
采用顶空固相微萃取结合气相色谱-质谱联用法分析香荚兰提取物挥发性香气成分组成。以感官为导向,利用嗅觉阈值、香气活性值(odour active value,OAV)及香气重组实验研究香荚兰提取物特征风味物质并进行重构。结果表明,香荚兰提取物中共检出83种香气成分,与香荚兰提取物特征风味密切相关的奶香、甜香、酸香、膏香、焦香、豆香和辛香香韵特征成分共有34种。基于OAV判断香兰素、4-(乙氧基甲基)苯酚、愈创木酚、乙酸、4-乙烯基愈创木酚、香草醇乙醚等14种化合物为香荚兰提取物特征风味的关键贡献成分。14种关键贡献成分的重组样品具有香荚兰样的奶香、甜香、烟熏香和酸香,香荚兰特征香气风格辨识度明显,与香荚兰特征风味天然香原料的感官相似度达92.33%。香兰素、4-(乙氧基甲基)苯酚、愈创木酚、乙酸、4-乙烯基愈创木酚、香草醇乙醚、乳酸乙酯等14种化合物被鉴定为香荚兰特征风味物质,可作为香荚兰特征风味天然香原料质控的关键指标,也可为复配重构香荚兰特征风味添加剂提供物质基础。  相似文献   
15.
本文比较集中地介绍了国外香荚兰产业发展的历史背景及香荚兰豆品质评价的现状及发展趋势。倾力想让更多的中国人走近香英兰豆、了解香荚兰豆、应用香荚兰豆,为中国人的生活献上一份魅力无限的芬芳。  相似文献   
16.
This article presents the results of an investigation of the effect of pre-dehumidifying the drying air before it is heated and supplied into a batch tray dryer. Dehumidification is achieved through moisture condensation as the air flowing through a coil is cooled by chilled water from a cold source. As an example, this process is applied to the drying of vanilla and is based on a numerical method already validated by former results. Then, it is established through comparisons with a conventional batch tray dryer model that pre-dehumidification significantly reduces drying time. Furthermore, preheating air by an intermediate heating source reduces total energy consumption of the primary heating system to a level depending on the preset drying temperature. As regards batch tray dryer design and optimization purposes, these results open up particularly interesting heating and cooling sources utilization prospects.  相似文献   
17.
香荚兰豆专题系列之一——世界香荚兰产业及市场概况   总被引:1,自引:0,他引:1  
本文从香荚兰豆独特的功能及效用切入主题,简明扼要地介绍了世界香荚兰产业及市场的发展进程及现况。作者在长期的研究及生产实践中,收集并整理了首次公开发表的令人耳目一新的统计数据及独到的分析,为读者提供了可作参考的最新信息。  相似文献   
18.
19.
Polyphenol oxidase (PPO) of Vanilla planifolia Andrews beans was extracted and purified through ammonium sulphate precipitation, dialysis, and gel filtration chromatography. PPO activity was measured by improved UV technique using 4-methylcatechol and catechol as substrates increasing substantial sensitivity of previous procedure. The optimum pH and temperature for PPO activity were found to be 3.0 and 3.4 and 37 °C, respectively. Km and Vmax values were found to be 10.6 mM/L and 13.9 OD300 min−1 for 4-methylcatechol and 85 mM/L and 107.2 OD300 min−1 for catechol. In an inhibition test, the most potent inhibitor was found to be 4-hexylresorcinol followed by ascorbic acid. The thermal inactivation curve was biphasic. Activation energy (Ea) and z values were calculated as 92.10 kJ mol−1 and 21 °C, respectively.  相似文献   
20.
A headspace-solid phase micro-extraction (HS-SPME) GC–MS method has been developed for the determination of coumarin, vanillin and ethyl vanillin in vanilla products. Limits of detection ranged from 1.33 to 13.2 ng mL−1. Accuracy and precision data for the method were measured and compared to those obtained using LC-ESI-MS. A survey of 24 commercially available vanilla products was completed using both techniques. No coumarin was detected in any of the samples. Examination of the GC–MS chromatograms revealed the presence of 18 other flavor related compounds in the samples. The method validation and sample analysis data using HS-SPME-GC–MS were comparable to those obtained using the LC–MS method. Because the two methods are conceptually different from one another, both methods would not be subject to the same interferences. This would allow them to be used as confirmatory methods for each other.  相似文献   
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